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What information is greatly lacking which does not allow us to propose a solid theory for origin of life ?
First of all, we do have some solid theories to explain the origin of life. That said, the main thing missing in order to be able to accept one of these theories with a decent amount of certainty is the ability to run a planetary scale experiment for a few billion years.
The theories are fine, the problem is that we cannot really test them. In order to test a theory that describes the origin of life, we will have to recreate the original conditions (think of a test tube the size of the Earth) and then pump energy into the system and watch what happens over the next few billions of years. This is not really feasible, for obvious reasons. I really doubt you will be able to get funding for an experiment that will run that long.
The reason for no single, solid origin of life (OOL) theory is that there are many and none of them explain or resolve the overall or the detailed issues of OOL, encompassing wide differential and even conflicting approaches, e.g., reproduction vs metabolism, and RNA vs DNA. Further, all are using naturalistic processes, requiring validation by the laws of physics and experimentation. While there are numerous theories, they are either geochemically irrelevant or outside the laws of physics. Whether RNA world, panspermia, hydrothermal vents, small warm ponds, all embrace various levels of chemical evolution for the initial, intermediate and ultimate biochemical assembly of increasingly more complicated levels of organic elements considered vital to OOL. No viable processes have been found to naturalistically create life.
Increasingly, wild speculation of geochemical conditions and trivialization of biochemical assembly, metabolism and reproduction are being proposed. The intractable problems that apply to naturalistic theories begins with the fact that chemical evolution of non-living compounds produces no viable pathway to increased complexity, that is, there are no cosmic evolutionary processes capable of the complex structure, design, order and operation of biochemical systems required for even the simplest organism.
The universal challenges that must be fully resolved in all theories include: 1. The homochirality essential in nucleotide amino acids, 2. The homopolymerization of the DNA side chains, 3. The nucleotide coding using information design, 4. The cell membrane formation essential encapsulation. 5. The chicken and egg issue of proteins and complex structures.
These are affected by requirements for colocation. coincidence, contamination mitigation and concentrations that are absolutely precise.
Finally, lab experiments must accurately reflect geochemically relevant conditions and not overly manipulated by experimenters, which would simulate intelligent design but produce questionable results.
The number of sources that could be listed is extensive. A simple search internet of the main descriptive words would provide detailed definition and additional detail. Regarding the 5 universal challenges: 1. homochirality relates to the right/left handedness of the amino acids since they are not symmetric. DNA amino acids must be 100% left handed or DNA will not work. One of the challenges to get comprehensive sourcing is due to the reluctance of present biological entities to fully acknowledge the delineated intractable issues.
As a Solution to the Origin of Life, RNA World Model Comes Under Attack
According to a recent article at New Scientist, “Why ‘RNA world’ theory on origin of life may be wrong after all,” the RNA world model of the origin of life is under attack:
Life has a chicken-and-egg problem: enzymes are needed to make nucleic acids — the genetic material — but to build them you need the genetic information contained in nucleic acids. So most researchers assume that the earliest life, long before the evolution of cells, consisted of RNA molecules. These contain genetic information but can also fold into complex shapes, so could serve as enzymes to help make more RNA in their own image — enabling Darwinian evolution on a molecular level.
At some point, the idea goes, this RNA world ended when life outsourced enzymatic functions to proteins, which are more versatile. The key step in this switch was the evolution of the ribosome, a structure that builds protein molecules from genetic blueprints held in RNA.
But such a transition would require abandoning the enzymatic functions of RNA and reinventing them in proteins. “That is not a simple model,” says Loren Williams, a biochemist at the Georgia Institute of Technology in Atlanta.
That’s a reasonable point at the end of the quote: If a self-replicating system has all of the enzymatic functions it needs from RNAs (something that hasn’t been demonstrated), then rebuilding that system using an entirely different type of molecule (proteins) would be an extremely difficult task and highly unlikely. Yet this is essentially precisely what the classical RNA world model requires.
But there are many other criticisms of the RNA world model. A 2012 paper in Biology Direct by biochemist Harold S Bernhardt keenly titled, “The RNA world hypothesis: the worst theory of the early evolution of life (except for all the others),” notes that “the following objections have been raised to the RNA world hypothesis”:
(i) RNA is too complex a molecule to have arisen prebiotically (ii) RNA is inherently unstable (iii) catalysis is a relatively rare property of long RNA sequences only and (iv) the catalytic repertoire of RNA is too limited.
Now the author himself accepts the view that the RNA world is the best materialistic model for the origin of life. But he’s very frank about its problems. For example, regarding the objection that “RNA is too complex a molecule to have arisen prebiotically,” he writes:
RNA is an extremely complex molecule, with four different nitrogen-containing heterocycles hanging off a back-bone of alternating phosphate and D-ribose groups joined by 3′,5′ linkages. Although there are a number of problems with its prebiotic synthesis, there are a few indications that these may not be insurmountable. Following on from the earlier work of Sanchez and Orgel, Powner, Sutherland and colleagues have published a pathway for the synthesis of pyrimidine nucleotides utilizing plausibly prebiotic precursor molecules, albeit with the necessity of their timed delivery (this requirement for timed delivery has been criticized by Benner and colleagues, although most origin of life models invoke a succession of changing conditions, dealing as they do with the evolution of chemical systems over time what is critical is the plausibility of the changes).
We covered the research of Powner and Sutherland here and here, pointing out that it was carefully designed to yield the desired results and noting how the goal-directed nature of the experiment undermines claims of the model’s plausibility under unguided natural conditions. Hence the criticism that it has an unlikely “requirement for timed delivery.”
Bernhardt then moves on to another criticism:
RNA is often considered too unstable to have accumulated in the prebiotic environment. RNA is particularly labile at moderate to high temperatures, and thus a number of groups have proposed the RNA world may have evolved on ice, possibly in the eutectic phase (a liquid phase within the ice solid).
But there’s a major problem with the “cold” origin of life hypothesis: at low temperatures, reactions become so slow that nothing interesting ever happens. That’s going to be a problem for many types of organic chemistry necessary for the origin of life. This is an especially significant problem when one considers that life appeared on earth very rapidly after conditions became favorable:
- “…we have now what we believe is strong evidence for life on Earth 3,800 thousand million years [ago]. This brings the theory for the Origin of Life on Earth down to a very narrow range … we are now thinking, in geochemical terms, of instant life…” (C. Ponnamperuma, Evolution from Space 1981.)
- “[W]e are left with very little time between the development of suitable conditions for life on the earth’s surface and the origin of life. Life is not a complex accident that required immense time to convert the vastly improbable into the nearly certain. Instead, life, for all its intricacy, probably arose rapidly about as soon as it could.” (Stephen Jay Gould, “An Early Start,” Natural History, February, 1978.)
A cold origin of life makes it much more difficult for life to arise under such a short timescale. Moreover, the notion that the early earth was cold rather than hot flies in the face of everything geologists have ever said about the conditions on the early earth.
Next, Bernhardt notes that “Catalysis is a relatively rare property of long RNA sequences only,” and he offers a nice discussion of the gross improbability of randomly producing a long, self-replicating RNA molecule:
The RNA world hypothesis has been criticized because of the belief that long RNA sequences are needed for catalytic activity, and for the enormous numbers of andomized sequences required to isolate catalytic and binding functions using in vitro selection. For example, the best ribozyme replicase created so far — able to replicate an impressive 95-nucleotide stretch of RNA — is
190 nucleotides in length, far too long a sequence to have arisen through any conceivable process of random assembly. And typically 10,000,000,000,000-1,000,000,000,000,000 randomized RNA molecules are required as a starting point for the isolation of ribozymic and/or binding activity in in vitro selection experiments, completely divorced from the probable prebiotic situation. As Charles Carter, in a published review of our recent paper in Biology Direct, puts it:
“I, for one, have never subscribed to this view of the origin of life, and I am by no means alone. The RNA world hypothesis is driven almost entirely by the flow of data from very high technology combinatorial libraries, whose relationship to the prebiotic world is anything but worthy of “unanimous support”. There are several serious problems associated with it, and I view it as little more than a popular fantasy” (reviewer’s report in ).
10 14 – 10 16 is an awful lot of RNA molecules.
Don’t miss what’s being said here: the argument directly parallels ID proponents who observe that it’s extremely unlikely for an RNA molecule with just the right nucleotide sequence needed for self-replication to arise by chance. In other words, he’s making the information sequence challenge to the origin of life.
Now Bernhardt proposes that perhaps the first self-replicating RNA was much shorter, reducing the probabilistic obstacles to randomly generating the right nucleotide sequence. But the evidence that this is actually possible is non-existent. Indeed, one of the reviewers, Eugene Koonin, points out that such a self-replicating RNA — whether long or short — has yet to be demonstrated:
I basically agree with Bernhardt. The RNA World scenario is bad as a scientific hypothesis: it is hardly falsifiable and is extremely difficult to verify due to a great number of holes in the most important parts. To wit, no one has achieved bona fide self-replication of RNA which is the cornerstone of the RNA World.
Finally, Bernhardt explains a fourth problem with the RNA world model, namely “The catalytic repertoire of RNA is too limited”:
It has been suggested that the probable metabolic requirements of an RNA world would have exceeded the catalytic capacity of RNA. The majority of naturally occurring ribozymes catalyze phosphoryl transfer reactions — the making and breaking of RNA phosphodiester bonds. Although the most efficient of these ribozymes catalyze the reaction at a comparable rate to protein enzymes — and in vitro selection has isolated ribozymes with a far wider range of catalytic abilities — the estimate of proteins being one million times fitter than RNA as catalysts seems reasonable, presumably due to proteins being composed of 22 chemically rather different amino acids as opposed to the 4 very similar nucleotides of RNA.
While Bernhardt discusses the various kinds of reactions that RNA can catalyze, he admits “RNAs are, in most cases, worse catalysts than proteins.” That sounds like Bernhardt just conceded the validity of the criticism that he described against the RNA world. Somehow, however, he manages to spin the inferiority of RNA catalysis, turning it into not a knock against the RNA world, but an argument for it: “This [the inferior catalytic abilities of RNA] implies that their [RNA’s] presence in modern biological systems can best be explained by their being remnants of an earlier stage of evolution, which were too embedded in biological systems to allow replacement easily.”
So RNA is used by living organisms — despite its inferior catalytic abilities — only because evolution wasn’t able to replace it? But aren’t we constantly told how proteins can evolve to accommodate virtually any need of an organism? Doesn’t this suggest severe limits to the evolvability of proteins? Now it seems that limits to evolution have become an argument for evolution.
This tortured logic brings us back to the criticism raised in the recent New Scientist article: the RNA world model is unlikely to be correct because it requires that proteins (with superior chemistry-catalyzing abilities) somehow swooped in and replaced what RNA was doing. That seems very unlikely. But Bernhardt again tries to spin this dilemma into an argument for the RNA world — that difficulties replacing RNA with protein point to the fact that RNA was once a precursor of life. However, if it’s so hard to replace RNA with proteins, how do we know that it happened in all the other cases required by the RNA world model?
It seems that whether proteins did or did not replace RNA, we’re being told that in either case that’s evidence for the RNA world. No wonder Eugene Koonin called the model “unfalsifiable.”
So why does anyone prefer the RNA world model, given all its problems? Koonin provides the answer in his reviewer’s comments at the end of Bernhardt’s article — it’s because he requires some materialistic model, and other materialistic models clearly won’t explain the origin of replication:
[T]he RNA World appears to be an outright logical inevitability. ‘Something’ had to start efficiently replicating to kick off evolution, and proteins do not have this ability.
Koonin’s argument thus goes like this: We know that unguided evolution is true, so some evolutionary model must be correct. If other unguided models of life’s origins won’t work, then the RNA world must be correct, because “something” had to happen to get life started.
But what if the RNA world itself has many problems and so it isn’t a viable solution? That’s not an option Koonin seems willing to consider. He’s right that “something” has to get life started. But there is a third way that Koonin hasn’t considered. That third way — the “something” he won’t consider — is the only known cause that can generate the kind of highly complex and specified digital sequences required at the origin of life: intelligent design.
If atoms are mostly empty space, why do objects look and feel solid?
Why can’t we see the spaces? Credit: Shutterstock
Chemist John Dalton proposed the theory that all matter and objects are made up of particles called atoms, and this is still accepted by the scientific community, almost two centuries later. Each of these atoms is each made up of an incredibly small nucleus and even smaller electrons, which move around at quite a distance from the centre.
If you imagine a table that is a billion times larger, its atoms would be the size of melons. But even so, the nucleus at the centre would still be far too small to see and so would the electrons as they dance around it. So why don't our fingers just pass through atoms, and why doesn't light get through the gaps?
To explain why we must look at the electrons. Unfortunately, much of what we are taught at school is simplified – electrons do not orbit the centre of an atom like planets around the sun, like you may have been taught. Instead, think of electrons like a swarm of bees or birds, where the individual motions are too fast to track, but you still see the shape of the overall swarm.
In fact, electrons dance – there is no better word for it. But it's not random dancing – it's more like ballroom dancing, where they move in set patterns, following steps laid down by a mathematical equation named after Erwin Schrödinger.
These patterns can vary – some are slow and gentle, like a waltz whereas some are fast and energetic, like a Charleston. Each electron keeps to the same pattern, but once in a while it may change to another, as long as no other electron is doing that pattern already. No two electrons in an atom can do the same step: this rule is called the Exclusion Principle.Electrons are like a swarm of birds. Credit: John Holmes/Wikimedia Commons, CC BY-SA
Although electrons never tire, moving up to a faster step does take energy. And when an electron moves down to a slower pattern it loses energy which it gives out. So when energy in the form of light falls on an electron, it can absorb some energy and move up to a higher, faster "dance" pattern. A light beam won't get far through our table, since the electrons in all the atoms are eager to grab some energy from the light.
After a very short while they lose this gained energy, perhaps as light again. Changes in the patterns of absorbed and reflected light give reflections and colours - so we see the table as solid.
Resistance when touched
So why does a table also feel solid? Many websites will tell you that this is due to the repulsion – that two negatively charged things must repel each other. But this is wrong, and shows you should never trust some things on the internet. It feels solid because of the dancing electrons.
If you touch the table, then the electrons from atoms in your fingers become close to the electrons in the table's atoms. As the electrons in one atom get close enough to the nucleus of the other, the patterns of their dances change. This is because, an electron in a low energy level around one nucleus can't do the same around the other – that slot's already taken by one of its own electrons. The newcomer must step into an unoccupied, more energetic role. That energy has to be supplied, not by light this time but by the force from your probing finger.
So pushing just two atoms close to each other takes energy, as all their electrons need to go into unoccupied high-energy states. Trying to push all the table-atoms and finger-atoms together demands an awful lot of energy – more than your muscles can supply. You feel that, as resistance to your finger, which is why and how the table feels solid to your touch.
This article was originally published on The Conversation. Read the original article.
Ordinary chemistry produces racemates
A well-regarded organic chemistry textbook states a universal chemical rule in bold type:
This is a consequence of the Laws of Thermodynamics. The left and right handed forms have identical free energy (G), so the free energy difference (&DeltaG) is zero. The equilibrium constant for any reaction (K) is the equilibrium ratio of the concentration of products to reactants. The relationship between these quantities at any Kelvin temperature (T) is given by the standard equation:
where R is the universal gas constant (= Avogadro&rsquos number x Boltzmann&rsquos constant k) = 8.314 J/K.mol.
For the reaction of changing left-handed to right-handed amino acids (L &rarr R), or the reverse (R &rarr L), &DeltaG = 0, so K = 1. That is, the reaction reaches equilibrium when the concentrations of R and L are equal that is, a racemate is produced. This explains the textbook rule above.
Origin Of Life: The Panspermia Theory
SiS is proud to feature the winners of the "2008 Integrated Graduate Program in the Life Sciences (IGP) Science and Society Class Distinction Award." Written as part of a course on science and society, these papers were chosen by IGP faculty to be published on SiS. This month, we present the following piece by PhD student Sonali Joshi.
How life originated on earth is a question that people have pondered for ages. Theories abound, from those based on religious doctrine, to the purely scientific, to others that border on science fiction. One possibility that hovers on this border is the panspermia theory, which suggests that life on Earth did not originate on our planet, but was transported here from somewhere else in the universe. While this idea may seem straight out of a science fiction novel, some evidence suggests that an extraterrestrial origin of life may not be such a far out idea.
One argument that supports the panspermia theory is the emergence of life soon after the heavy bombardment period of earth, between 4 and 3.8 billion years ago. During this period, researchers believe the Earth endured an extended and very powerful series of meteor showers. However, the earliest evidence for life on Earth suggests it was present some 3.83 billion years ago, overlapping with this bombardment phase. These observations suggest that living things during this period would have faced extinction, contributing to the idea that life did not originate on Earth.
However, in order for life to originate elsewhere in the universe, there would have to be an environment on another planet capable of supporting it. Our study of the universe suggests that life as we know it would have a hard time surviving outside of the Earth. But, it is important to note that life on Earth can withstand many extreme conditions. Some bacteria grow at temperatures as high as 113°C. At the other end, microbes can thrive at temperatures as low as -18°C many can be preserved in liquid nitrogen at -196°C. They can also tolerate high doses of ionizing and UV radiation, extreme pressure, etc. These observations suggest that it is difficult to define the conditions that favor life, and make it harder for us to predict that life is unique to Earth.
The presence of water elsewhere in the universe reinforces this. Mars is believed to have contained water in the past. Much excitement for the presence of life on Europa, one of Jupiter’s moons, has been fueled by speculations that it may have underground oceans. However, while water is essential for life that we are familiar with, its presence does not necessarily indicate the presence of life.
The fact that organic matter is relatively common in space could also support the idea of extraterrestrial life. Organic matter refers to matter composed of compounds that contain carbon. All living things on Earth are carbon-based. A variety of organic compounds have been detected in meteorites that have landed on earth, including amino acids, which are the building blocks of proteins (and proteins are primary components all of living cells). The presence of carbon-based matter in meteorites supports the possibility that life on our planet could have come from outer space. But, even though life on earth is composed of organic matter, organic matter itself is not considered life.
Even if extraterrestrial life did exist, proponents of the panspermia theory must still determine how life arrived on Earth. The best candidates to act as “seeds of life” are bacterial spores, which allow bacteria to remain in a dormant state in the absence of nutrients. Bacteria constitute about one-third of Earth’s biomass and are characterized by their ability to survive under extreme conditions—those that we initially believed were unable to support life. In light of panspermia, the important question is if bacteria or bacterial spores could survive in space.
To address this question, scientists at the German Aerospace Centre in Cologne designed experiments using the Russian FOTON satellite. They mixed bacterial spores with particles of clay, red sandstone, Martian meteorite or simulated Martian soil to make small lumps a centimeter across. The lumps were then exposed via the satellite to outer space. After two weeks of exposure, researchers found that nearly all of the bacterial spores mixed with red sandstone were able to survive. Another study showed that bacterial spores could survive the extreme conditions of outer space for six years if they were protected from extraterrestrial solar UV radiation. This would be possible if the spores traveled within comets or meteorites.
However, interplanetary distances are large, so the time a bacterial spore would have to spend in a meteorite or comet before hitting a host planet could range in the millions of years. Two studies involving the isolation of bacterial spores, either from the abdomen of extinct bees preserved in amber or from a brine inclusion in an old salt crystal from the Permian Salado formation, suggest that bacterial spores can remain viable for up to 250 million years. Thus, bacterial spores could potentially account for life on earth.
But are there bacterial spores floating through space? One study focused on the heat radiation emitted from Halley’s Comet's dust particles as the comet approached the sun. The particles' radiation fingerprint corresponded surprisingly well to that of bacteria heated to elevated temperatures – no material other than bacteria matched the observed spectrum. As comets are known to have collided with Earth at different points in the past, this observation presents an interesting argument for panspermia. While this study does not provide conclusive evidence for presence of life in outer space, it does raise the possibility that our galaxy may be littered with bacterial spores.
An important thing to note about the panspermia hypothesis is that it gives no explanation for how life that arrived on Earth came to be. Even if we are able to show that life on Earth was a result of panspermia, the question of where and how life originated will be a lot harder to answer. So far our knowledge of the solar system suggests that life is unique to Earth, but, as science and technology advance, we will have to modify ideas that we currently regard as facts. It remains to be seen if the questions regarding the origin of life on Earth and the origin of life in the universe have the same answer.
Was Darwin Wrong?
My friend James McClellan, a distinguished historian of science, likes ribbing me about my insistence that science&rsquos glory days are over. In The End of Science I contended that science will keep extending and tweaking its current paradigms, like evolution by natural selection and the big bang, but there won&rsquot be any more comparably profound &ldquorevelations or revolutions.&rdquo
Jim enjoys rubbing my face in possible contradictions to my thesis. Recently he drew my attention to&mdashand bought me a copy of, hard cover!&mdashThe Tangled Tree: A Radical New History of Life, by journalist David Quammen. The book&rsquos blurb claims that our scientific view of life is undergoing a big shake-up. So I read the book. [*See Jim&rsquos response to this column below.]
Quammen has a reputation as a terrific science writer, which turned out to be deserved. Tangled Tree is an epic tale about science&rsquos quest to understand life. Quammen does for evolutionary biology what Dennis Overbye did for cosmology, the quest to understand the universe, in Lonely Hearts of the Cosmos, one of my favorite science books. Both writers capture the thrills and messiness of research into nature&rsquos deepest mysteries.
Just as Overbye&rsquos story revolves around an obsessive, uncompromising curmudgeon, astronomer Alan Sandage, so does Quammen&rsquos. His anti-hero is Carl Woese, inventor of a powerful molecular method for tracing evolutionary lineages. With it, Woese compiled evidence for a major new form of single-celled, prokaryotic life, Archaea, from which we may have descended.
Woese, who died in 2012 (and whom I interviewed in 1990 for an article on the origin of life), was a would-be revolutionary who thought he was under- and Darwin over-appreciated. He once wrote on a colleague&rsquos manuscript, &ldquoYou accord Darwin so much more substance than the bastard deserves.&rdquo Woese sought alternatives to natural selection as the major force underpinning evolutionary change, such as Stuart Kauffman&rsquos concept of self-organized complexity (which I critiqued in End of Science).
Archaea are one of the &ldquoradical&rdquo findings that Quammen describes. Woese convinced many biologists that Archaea are so distinct from bacteria that they deserve their own label. But Archaea do not pose a challenge to Darwinian theory, our understanding of how species originate and evolve. I would compare Archaea to a revision in our model of galaxy formation in the early universe, which does not threaten the basic big-bang framework.
Horizontal gene transfer, the other discovery on which Quammen focuses, arguably does pose a challenge to conventional evolutionary theory. It involves different species passing genes directly to each other, usually via bacterial or viral infections. Tentative evidence for horizontal gene transfer emerged almost a century ago, but only in the past few decades have biologists recognized its influence on the evolution of multicellular organisms as well as Archaea and bacteria.
Horizontal gene transfer, Quammen asserts, &ldquohas overturned the traditional certitude that genes flow only vertically, from parents to offspring, and can&rsquot be traded sideways across species boundaries.&rdquo Evolution has always been depicted by what Darwin called a &ldquogreat tree,&rdquo with countless branches, representing different species, diverging from a common ancestor. The tree metaphor, it turns out, is inaccurate, or incomplete. Some branches are &ldquotangled,&rdquo linked, by genes jumping from one species to another through horizontal gene transfer.
Scholars disagree on just how revolutionary horizontal gene transfer is. In 2000 W. Ford Doolittle reported on the implications of Archaea and horizontal gene transfer in Scientific American in &ldquoUprooting the Tree of Life.&rdquo The &ldquoconsensus tree&rdquo depicting evolution is &ldquooverly simplified,&rdquo Doolittle stated. A 2002 paper by Doolittle and others contended that horizontal gene transfer represents a &ldquoradical revision&rdquo of our view of life&rsquos early history.
In 2009 New Scientist raised the stakes with a cover story about horizontal gene transfer, titled &ldquoDarwin Was Wrong.&rdquo A statement, not a question. A subtitle added &ldquoCutting Down the Tree of Life.&rdquo (The online version of the article now has the softer headline &ldquoWhy Darwin Was Wrong about the Tree of Life.&rdquo) In the article philosopher John Dupre called horizontal gene transfer &ldquopart of a revolutionary change in biology.&rdquo My italics.
In a rebuttal, &ldquoDarwin Was Right,&rdquo philosopher Daniel Dennett and biologists Richard Dawkins, Jerry Coyne and P.Z. Meyers called the New Scientist article &ldquofalse&rdquo and &ldquoinflammatory.&rdquo &ldquoNothing in the article showed that the concept of the tree of life is unsound,&rdquo they said, &ldquoonly that it is more complicated than was realized before the advent of molecular genetics.&rdquo
Quammen, too, accuses New Scientist of sensationalism. Its headline may have &ldquohelped to sell magazines,&rdquo he comments, but it &ldquocaricatured the genuine challenge to Darwinian orthodoxy that the new discoveries raised.&rdquo Darwin &ldquocan&rsquot be blamed&rdquo for not anticipating horizontal gene transfer, Quammen states. &ldquoHe did the best he could, which was exceedingly well, with the evidence he could see.&rdquo
To answer the question posed in my headline: Nah. Far from being wrong, Darwin is as right as ever when it comes to his big idea, natural selection. He couldn&rsquot foresee all the sources of variation within and between offspring, which provide the raw material on which natural selection operates. He didn&rsquot know about genes, and he speculated, wrongly but reasonably, that acquired characteristics might be passed on to offspring, as Lamarck had proposed. (As Quammen notes, Lamarck&rsquos hypothesis has undergone &ldquosmall surges of reconsideration even down to the present day.&rdquo)
Now we know that variations have many causes, including mutation, endosymbiosis, genetic drift, sexual recombination, epigenetic factors and, yes, horizontal gene transfer. But all variations, whatever form they take, serve as fodder for natural selection, which remains the primary evolutionary force, and which Darwin (and Wallace) discovered.
Returning to the biology/cosmology analogy, evolution by natural selection and the big bang theory provide the basic frameworks for understanding life and the universe, respectively. Each paradigm constantly undergoes revisions and extensions. But just as the big bang theory absorbed the startling discovery two decades ago that the universe&rsquos expansion is accelerating, so evolutionary theory has easily encompassed horizontal gene transfer.
Thomas Kuhn distinguished between &ldquonormal&rdquo science, which buttresses the prevailing paradigm, and &ldquorevolutionary&rdquo science, which overturns the paradigm. Horizontal gene transfer and Archaea represent normal science, which fleshes out Darwin&rsquos revolutionary vision of life. All of biology since Darwin has been normal.
Carl Woese is hardly the only prominent modern thinker irked by Darwin&rsquos dominance. Karl Popper was not a fan, and neither are philosopher Jerry Fodor and cognitive scientist Massimo Piattelli-Palmarini, authors of What Darwin Got Wrong (which I dismissed as &ldquofatally flawed.&rdquo) But none of Darwin&rsquos critics has done him any serious damage. Evolution by natural selection resembles capitalism. Both paradigms have an uncanny ability to absorb opposition, just as one microbe swallows another via endosymbiosis.
That said, I find the discoveries on which Quammen reports fascinating. One subtheme of his book concerns how horizontal gene transfer might influence our self-conceptions. &ldquoWhat implications do these discoveries have for the concept of human identity?&rdquo Quammen asks. &ldquoWhat is a human individual? What are you?&rdquo Good questions. I just wrote a book about the quest to solve the mind-body problem, which asks, Who are we, really?
As Quammen reports, for every cell that is, strictly speaking, ours, our bodies contain roughly three bacterial cells&mdashin our guts, mouths and elsewhere. Bacteria are much smaller than human cells and yet still account for as much as three percent of our total mass. About eight percent of our genome consists of &ldquoremnants of retroviruses that have invaded our lineage,&rdquo Quammen says. We are &ldquomosaics.&rdquo We contain multitudes, and yet we are individuals.
A final point, or rather, prediction, which I first made in The End of Science. No matter how much they learn, biologists will never really know how matter first became animate, just as cosmologists will never know how the universe began. Moreover, we will never find a final, definitive answer to the question of who we really are. Science-lovers should be grateful for the persistence of these mysteries. As long as they endure, so will our quest for self-knowledge.
*Here is James McClellan&rsquos response to this column. For more on our ongoing argument about what Jim would call scientific &ldquotruth,&rdquo see also the introduction of my book Mind-Body Problems and the first three items in Further Reading.
I&rsquom flattered that you again mention me in your wonderful blog, but reading your latest, &ldquoWas Darwin Wrong?,&rdquo gives me pause on two counts.
First, you don&rsquot address the epistemological status of current evolutionary theory. Even supposing you&rsquore correct in all you say about evolution or about cosmology and the &ldquoend of science,&rdquo the implication that science has therefore determined unalterably true facts about nature is hardly self-evident or justified ipso facto. I thought for a while that you actually agreed with me that we are unable to escape the limitations of language and culture that box in any set of sentences we humans might utter, scientific or otherwise&hellipthat we are trapped in the chatter of us as slightly hairy apes trying to figure out our circumstances, but, alas, I see you are backsliding.
(BTW, such a post-modernist take on science hardly excludes glory days ahead for science! The stories science tells are perhaps the greatest stories ever told and stunning testimony to human achievement. Who knows what lies ahead if we get a handle on dark matter, the origins of life, or even, pace Horgan, consciousness. Your &ldquoend of science&rdquo trope is too small-minded.)
Secondly, I think Quammen is still correct that, all told, the successive discoveries surrounding Archaea, horizontal gene transfer, endosymbiosis, the microbiome and all the rest constitute a new view of life and a rewriting of the story of evolution, perspectives very different from those found in The Origin of Species. Put simply, changes in quantity have produced a change in quality, and in my view we live in a different world now regarding our understandings of life and its meanderings. &ldquoNatural selection&rdquo may still be a driver, but the context has changed fundamentally, and thus so also has the meaning of natural selection itself.
Like you, I don&rsquot see these changes as effecting a revolution per se, but what&rsquos happened in recent decades is not Kuhnian &ldquonormal science&rdquo either. Scientists across a broad range of disciplines (genetics, taxonomy, paleontology, etc.) are not working out problems dictated by the Darwinian paradigm, they have made dramatic new discoveries in entirely new areas that have radically reframed that paradigm and the context in which to think about life and its history. There is grandeur in this new view of life, so why force it into the Procrustean bed of nineteenth-century theorizing?
An end to the war between evolution and Christian theology?
Catholic philosopher Kenneth W. Kemp skillfully argues that much of the modern conflict between science and religion has a great deal to do with scientists and the faithful overstepping their respective authority or expertise.
Strange things were demanded of many young Evangelicals in the twentieth century. Perhaps topping the list were the exhortations to question, criticize, and even ridicule evolutionary science, which, we were told, represented a direct assault on God and the Bible. I remember my youth group leader telling a teenager-packed room that the duckbill platypus presented comic, irresolvable problems for evolutionary biology. We were schooled in the scientific skepticism of Creation Museum founder Ken Ham ( don’t trust that carbon-14 dating !). Later we learned impressive phrases such as anthropic principle and irreducible complexity to stump our interlocutors.
The War That Never Was: Evolution and Christian Theology , by Catholic philosopher Kenneth W. Kemp, charts the recent history and arguments that brought about this peculiar paradigm, in which many in the West came to view science and religion as diametrically opposed. As Kemp skillfully argues, much of this conflict has more to do with scientists and the faithful overstepping their respective authority or expertise, by believing that science (or the Bible) answer questions they are not capable of answering. He writes:
[T]he ideas of creation and evolution are answers to fundamentally different questions. The doctrine of creation offers an account of the very existence of the world, of its dependence for that existence on God. Theories of evolution, by contrast, explain not the existence of the world, but how it got to be the way it is.
An example of this overstepping is manifested in University of Chicago biologist Jerry A. Coyne’s claim that, “evolution gives us the true account of our origins, replacing the myths that satisfied us for thousands of years.” Cornell historian of biology William B. Provine was even more sensational, claiming that Charles Darwin understood that if natural selection were true, “then the argument from design was dead and all that went with it, namely the existence of personal god, free will, life after death, immutable moral laws, and ultimate meaning in life.” Atheist and evolutionary biologist Richard Dawkins in turn has called religious catechesis of one’s children a form of “child abuse,” because science disproves God’s existence.
Such attacks have led many Christians, particularly those of a fundamentalist stripe, to resist what they perceive as the immediate threat: evolutionary science. Yet this was always misguided, because the attacks on faith, though often made by scientists, were not actually scientific. If God is immaterial and transcendent, as Christians have historically claimed, no purely materialist intellectual endeavor, regardless of its complexity or nuance, can disprove him. The same is true for the human soul and its powers of intellect and will — if they are immaterial, no biological research can demonstrate they don’t exist. The existence (or non-existence) of God and free will are philosophical questions, not biological ones.
Moreover, as Kemp explains, the history of the battle between evolution and Christianity is not as binary or Manichean as it is typically presented in such popular accounts as the 1955 play Inherit the Wind, which tells the story of the famous 1925 Scopes “Monkey Trial.” Take for example the famous 1860 Oxford evolution debate , now an integral part of the mythology of anti-religion evolutionists who posit a “science v. religion” war. As “Darwin’s bulldog” Thomas Huxley later admitted, “the supporters of Mr. Darwin’s views in 1860 were numerically extremely insignificant. There is not the slightest doubt that, if a general council of the Church scientific had been held at that time, we should have been condemned by an overwhelming majority.”
Indeed, whether we consider biology or other “hard” sciences, resistance to new ideas comes just as much, if not more from within the scientific community itself than it does from pious believers. Kemp writes: “Even among scientists, there is always controversy between those eager to embrace new ideas and those appreciative of the power of the old ideas and doubtful of the values of the new.” Nor is science as monolithic as many of its anti-religion proponents like to claim. Consensus among the experts often takes a long time to coalesce, and, as any student of the history of science knows, is sometimes upended by new research or ideas.
Moreover, since Darwin’s 1859 On the Origin of the Species, plenty of Christians, including prominent theologians and philosophers, have been sympathetic toward, if not explicitly supportive of, many Darwinian ideas. The Southern Presbyterian Church, the locus of a famous controversy over evolution in the late nineteenth century, was a battle between theologians over evolution’s merits. During William Jennings Bryan’s misguided early twentieth century crusade against evolution, many scientists, such as Asa Gray, James Woodrow, and William Louis Poteat embraced evolution while remaining devout Protestants. They could do so because there remain many unresolved debates among Christians over the proper interpretation of Genesis.
Of course, the blame for invigorating this pseudo-war lies not only with fundamentalists like Bryan but also with anti-religion polemicists like Huxley or Andrew Dickson White. Many scientists, and even journalists including H.L Mencken, have eagerly sought to exploit various scientific theories to undermine Christian faith. Ella Thea Smith’s popular 1950s textbook Exploring Biology at times veered away from science by ridiculing those who believe humans to be the most evolved mammals. The National Science Foundation’s 1960’s Man: A Course of Study was widely interpreted as claiming that morality is solely a “product of our culture.”
More recently, an unnamed textbook cited by the California Board of Education in 1972 claimed “science is the total knowledge of facts and principles that govern our lives, the world, and everything in it.” A 1995 statement by the National Association of Biology Teachers, in turn, defined evolution as necessarily incompatible with the idea of design supervision or a personal God. With such unscientific assertions being peddled as incontestable truth, it’s understandable why American Protestants often felt the need to fight back.
One of the more recent manifestations of this resistance has been the Intelligent Design movement, promoted by people including Catholic biochemist Michael J. Behe, evangelical mathematician William A. Dembski, and evangelical UC Berkeley law professor Phillip E. Johnson. Though more intellectually nuanced than the fundamentalist-led biblical creationism, it sometimes suffers from similar weaknesses by proposing theses that science simply cannot prove.
Take irreducible complexity, an idea popularized by Behe, which proposes that some organisms are so irreducibly complex that they could not possibly evolve on their own without some sort of intelligent intervention. In response, Kemp notes that we lack sufficient knowledge of structures and processes to make the kinds of claims Behe makes. He cites as one example the human blood-clotting cascade, noting that even Behe has acknowledged, “it’s often quite difficult to sort out just who is activating whom.” Other structures and processes, alternatively, we actually do know enough to recognize them as not irreducibly complex—the blood-clotting cascade is more complex than bare functionality requires, evidenced by the fact that parahemophiliacs who lack one of the enzymes involved in the cascade can live long lives without out, and that whales and other sea creatures also lack parts of it . Finally, many evolutionists have offered a reasonable account of how Darwinian processes can produce irreducible complexity—for example, such a system can be built gradually by adding parts that are initially only advantageous, but eventually become essential. Indeed, Richard H. Thornhill and David W. Usserty have distinguished two “routes” of Darwinian evolution that they argue can produce the precise kind of complexity that Behe claims is beyond the reach of Darwinian processes.
Perhaps, then, it’s best if Christians take their lead from the many philosophers, theologians, and scientists who argue that there really need be no conflict between religious faith and evolutionary science, and that what conflict do exist are often because evolution has been exploited to make assertions beyond its own area of knowledge. Doing otherwise, as many well-intentioned Christians have done in recent centuries, has perhaps done more harm than good. St. Augustine puts it well when he writes:
If [non-Christians] find a Christian mistaken in a field that they themselves know well and hear him maintaining foolish opinions about our books, how are they going to believe those books concerning the resurrection of the dead, the hope of eternal life and the kingdom of heaven, when they think that their pages are full of falsehoods on facts which they themselves have learnt from experience and the light of reason?
One can only guess how many people have rejected Christianity because it was presented to them as synonymous with an anti-intellectual, anti-evolutionary fundamentalism.
For Catholics, the “Warfare Thesis,” as Kemp calls it, is especially misleading and erroneous. Many Catholics since the second century have believed that the Hexaëmeron, or six days of creation described in Genesis 1, are not temporal days. St. Augustine, St. Albert the Great, and Tommaso de Vio, Cardinal Cajetan all believed as much, long before Darwin’s famous voyage on the Beagle. As historians Rodney Stark and William J. Slattery have argued in their recent respective books Bearing False Witness: Debunking Centuries of Anti-Catholic History and Heroism and Genius: How Catholic Priests Helped Build — and Can Help Rebuild Western Civilization, the Catholic Church has always been supportive of science.
Indeed, the scientific method itself originated in a Christian philosophical system, practiced by Catholic clergy who believed the natural world was predictable and knowable because it was created by a rational God. Many of the earliest scientists were not only men of faith, but men of the cloth (e.g. Gregor Mendel). English biologist and Catholic St. George Mivart, who wrote an account of the intersection of theology and evolutionary biology, was in 1876 awarded an honorary doctorate by Pope Pius IX. And the big bang theory was first proposed by Belgian physics professor Msgr. Georges Lemaître. For anyone who still believes in this pseudo-war, or knows someone who does and needs persuading otherwise, Kemp’s book is essential reading.
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Evolution, religion, and why it’s not just about lack of scientific reasoning ability
Despite overwhelming evidence for evolution, many people still choose to reject it as an explanation for how humans and other organisms evolved and developed. This attitude seems to be especially common amongst religious people. But why is that, and what can we do to reconcile these two opposing worldviews? A new study published in Evolution: Education and Outreach tries to explain.
Why reject evolution?
Humans have long wondered and debated the scientific and theological explanations for our world and the life upon it. Scriptural accounts describe the creation as a series of events by a creator resulting in earth’s current diversity (including humans), whereas, science suggests descent with modification from a common ancestor over long periods of time (evolution), resulting in the vast diversity we see today (again, including humans).
Despite overwhelming evidence for evolution, a large portion of the US (and the world) continues to reject the theory. The question becomes why, in the face of so much convincing evidence, do people still not accept evolution as a process that occurs to shape the existence of life on this planet?
Hypotheses about causes of rejection
The second deficit model based hypothesis is that people reject evolution because they lack scientific reasoning ability. This hypothesis is the basis of our current study.
The research literature demonstrates that religion is a major barrier to the acceptance of the theory of evolution. What is it exactly about ‘religious’ individuals that causes rejection of scientific evidence?
Two prominent hypotheses stem from a ‘deficit model’. The first supports the idea that a deficiency of knowledge is to blame for rejecting evolution and that people reject evolution out of simple ignorance of the facts, the evidence, and the mechanisms. However, the literature demonstrates that in most cases, a simple education in the facts is not enough to change people’s minds.
The second deficit model based hypothesis is that people reject evolution because they lack scientific reasoning ability. This hypothesis is the basis of our current study. If true it presents a pedagogical impediment because the challenge becomes more than just teaching students the facts, but teaching them scientific reasoning skills (a much harder feat, according to research).
To test for a relationship between underlying scientific reasoning ability and acceptance of evolution, we specifically targeted religious individuals based on the fact that religion seems to be the underlying deterrent to evolution acceptance. Participants were asked to respond to a survey to rate their religiosity, complete a measure of their scientific reasoning ability, and to respond with their degree of agreement with various creationist and evolutionary statements.
We produced a model of the relationships between these factors where we hypothesized that scientific reasoning ability would predict both religiosity and agreement or disagreement with evolutionary statements. We were intrigued (yet not surprised) that there appears to be no relationship between the scientific reasoning ability of religious people and their acceptance of evolution. Nor was there a relationship between scientific reasoning ability and religiosity among our study group. Not surprising, however, is that religiosity is a negative predictor of the acceptance of evolution (a finding that has been thoroughly verified in the literature).
What does the data mean?
There is not a deficit in an underlying ability to reason that causes religious people to reject evolution. Our data clearly shows that individuals can be highly adept at scientific reasoning and still reject evolution (most likely on religious grounds). Our data also shows that one can be severely lacking in scientific reasoning ability and still accept evolution. It appears from this study that worldview (or religion), not intelligence, is the main driver of this decision.
What does this mean for education?
Our data clearly shows that individuals can be highly adept at scientific reasoning and still reject evolution (most likely on religious grounds).
In a recent editorial in Science Magazine, Dr. Katherine Hayhoe discusses an eerily similar dilemma in the realm of public acceptance of Climate Change. She argues that most scientists assume that providing more data to individuals will change their minds but research is showing this doesn’t work! Why? Because it has “much more to do with identity and ideology than data and facts”. This parallels what we are finding in evolution education. Data and facts are not enough. It is a worldview issue.
A likely solution is to offer students pathways that allow them to maintain their worldview while accepting the scientific facts. In our current research, we propose the use of a ‘Reconciliatory Model Approach’, one in which students are encouraged to find a bridge between the science and their religious beliefs. And this approach, at least preliminarily, appears to be working. The goal is to still cover the facts and encourage sound scientific reasoning, but approach it with a goal of reconciliation rather than assuming a deficit model and suggesting that their lack of acceptance is due to ignorance.
Why is it important?
Our goal is to show that scientific reasoning ability is not predictive of evolution acceptance among religious individuals and that science and religion do not have to be mutually exclusive, as they are so often portrayed to be. We hope to expand our efforts to include a religious as well as other religious denominations to continue to investigate the barriers to evolution acceptance with the end-goal being to create pedagogical implementations that successfully teach evolution such that the public is more educated and accepting of the foundational theory of biology, a theory that has profound implications for human health, conservation, and the preservation of our biodiversity.
Liked the blog? Now read the research:
Scientific reasoning ability does not predict scientific views on evolution among religious individuals
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“But why is that, and what can we do to reconcile these two opposing worldviews?” Probably because ‘religious’ thought most often begins with the idea that ‘we’ arre made in the ‘image and likeness’ of a creator God. Even though the I&L remains undefinable. And as the religious project ideas of morality and spiritiuality onto that I&L and thus themselves, it sits badly with assumptions and observations of human nature that come with evolutionary theory. Being made in the I&L of a creator God is a comforting thought. But probably a self deception because it’s easier to hold to that idea than confront the unholy truth of human nature itself.
It’s good you did the study to confirm, but this should not be a surprise. Your implicit postulate was wrong. Humans are not rational animals. There’s tons of research on this. See Kahneman & Tversky, Leonard Mlodinow, Antonio Damasio, V.S. Ramachandran, Timothy Wilson @ UoVirginia, Dan Ariely for popular accounts. There’s plenty more. It doesn’t matter if subjects are liberal or conservative, religious or not (as you point out). Decision-making and thinking is derives from cognitive biases, which, once set, are held onto tenaciously. Most people who accept evolution don’t understand it very well. Their adherence to scientific ideas isn’t generally based on empirical understanding, but is rather the fortunate bias towards science (good for us!). Well, maybe just a little bit of rationality…
Evolution and fundamentalist religion are incompatible. Evolution says that humans are not a special creation of God but evolved from simpler forms of life and are just part of the animal kingdom. Fundamentalist believers cannot accept this because it would destroy their whole world view. Life would be nothing for them. Reason and evidence and education have no effect on them.
I’d also suggest the 2 meanings of “Theory” causes confusion as most people do not understand the scientific meaning.
Nice article, but, as a writing teacher, I would have failed your last sentence. It is a disaster of prepositional phrases. This makes your conclusions unclear. If you wish to reach a larger audience effectively, I suggest revision of this sentence. Good luck, Jane
science and religion must be contradictive in the matter of evolution, namely because of a controversial soul that can not be evolving. Evolutionary theory proves its non-existence, and thus breaks the source of livelihood for the churches, and the possibility of its rule over the people doctrines the afterlife. By the way, Jesus did not acknowledge Plato’s concept of the immaterial soul and only proclaimed the bodily resurrection
It absolutely has to do with identity and ideology. The scientific establishment initially approached evolution as a refutation of religious views and was therefore regarded by many to be based less on fact than antagonism toward religion. It has taken many years to undo the damage so that people can see beyond the fact that many scientists are hostile toward religion and evaluate the evidence for themselves. In the same way, Climate Change has been paraded in front of the public in the guise of sweeping changes to taxation and heavy modification of lifestyle choices without a strong rationale for their positive impact. . Instead the approach should be on mitigation of risks associated with Climate Change such as discouraging settlement in coastal areas and shoring up threatened areas. The mantra that there is a consensus of support for this view from the very people most likely to benefit from sweeping changes makes he argument less than persuasive.
Many people are surely SMART enough to, upon accepting evolution – it’s mindless and un-directed (godless) implications and other worldview-altering, science-given realizations (as our insignificant position on a spect of cosmic dust in an unimaginably vast universe) wind up at a terminus of non-belief or atheism. However, it seems to me that, in order to make the leap to such a terminus, most people are just not BRAVE enough.
“Despite overwhelming evidence for evolution”
I guess we get to play the dishonest Darwinian game of semantics…. Before we continue… YOU need to clarify what you mean SPECIFICALLY when you use the duplicitous and purposely vague term “Evolution”.. DO YOU MEAN.. Variation, Adaptation, Speciation or ….De-volution. i.e. ..Finches beaks, Cave fish going blind, Moth colors, Weak bacteria lacking enzymes targeted by antibiotics, Dog ears, Mutated fruit flies with 2 WORTHLESS extra wings, Bear coats, Dog Ears and Squirrel tails? OR DO YOU MEAN Slow Microbe to Microbiologist (UCA for all flora and fauna) You will be required to put your cards on the table here in this classroom.
YOU HAVE NO EVIDENCE.. YOU HAVE ONLY WISHFUL SPECULATION, UNVERIFIED HYPOTHESIS, HOPEFUL GUESSES AND JUST SO STORIES… IF YOU THINK I AM WRONG, JUST TRY POSTING SOME OF THIS SO CALLED “EVIDENCE” FOR UCA FOR ALL FLORA AND FAUNA (TOE) AND SEE WHAT HAPPENS TO IT… WHAT HAVE YOU GOT TO WORRY ABOUT? YOU SHOULD HAVE NO TROUBLE PROVIDING EMPIRICAL SCIENTIFIC EVIDENCE TO SUPPORT SLOW MICROBE TO MICROBIOLOGIST EVOLUTION OVER BILLION YEARS””
What is the “overwhelming evidence” for evolution? Googled: “A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results.” The evidence is that there are varieties of life today… and then there are fossils. Setting aside DNA for now as the estimated half life for DNA (which is not a constant) is approx 521 yrs, so very likely there is no reliable DNA connections that can be made from fossils (further, DNA similarity in living creatures today does not automatically equate to an evolutionary relationship–it just means similar coding for similar function… sorry if your PhD taught you otherwise). What’s left is primarily a study of the geologic column and morphology of the fossils themselves. Fossils form by rapid burial and are, at best, an approximation of the location of the plant/animal at the time it was buried. This gives little assurance though as to the time of death, and less assurance still as to the time the creature (and other creatures like it) lived–it may have existed for a long time until later one was buried rapidly and fossilized. Morphology is a bit of a guessing game as most fossils are incomplete, and when multiple fossils of the same animal can be brought together to get a complete skeletal structure, that’s what you have… a skeleton (ta-da). This will give a general sense of the size, structure and mass of a creature but nobody knows how it really looked, behaved, etc… this is done by analogy, by inferences, by likening the fossil to the skeletal structure of living creatures today. By it’s nature then, this process is going to lead to assumptions and making connections between life forms alive today and those that are now extinct, but in reality (going back to scientific theory), no real measurable, repeatable, observable connection has actually been made. Moving past fossils, let’s look at the present – evolution can be said to be occurring here in the present and we see variability in life today (think of all the variations of canines, for example). That is true, observable, measurable, and repeatable, right? Yes, and that is good (real) science. Unfortunately, all varieties of canines are still canines (we don’t, for example, see them developing feathers, or flukes and flippers… nothing significant leading to the kinds of major evolutionary changes that Darwinian evolution relies upon). In fact, every experiment (think of Darwin’s finches of the Galapagos, or the long-term experiment of E.Coli) only supports minor variations – the finches adapted to the environment with varying beak sizes and the E.Coli was able to survive on citrate… but the finches remain finches and E.Coli remains E.Coli–natural selection and random mutation only carry organisms so far. From what is observable, conducting real scientific study here in the present, is that there is no tree of life, there are more like “bushes of life”. Going back the alleged hundreds of millions of years in the fossil record, we still see the same basic kinds of creatures that are still alive today. Where the fossil record is no friend to Darwinian evolution is that instead of a branching out tree of life, the tree is upside down – the fossils show there was once greater variety of life, but over time, that variety has lessened as creatures have gone extinct. Further, the fossil record gives the sudden appearance of life (ex. the Cambrian explosion) which also does nothing to support the notion of a progressive development from a single-celled amoeba to eventually what became a human being. So I come back to my original question, what is the “overwhelming evidence” again?? Evolution IS A faith-based religion: faith is defined as the assurance of things hoped for, the conviction of things not seen. This fits very well for those who insist we all evolved from bacteria from billions of years ago.
What is the overwhelming evidence for evolution? My understanding is that neo-Darwinian theory does a very good job of explaining the subtle/small changes in living organisms, but lacks the explanatory power to support the sudden arrival of new novel information in DNA, new biological systems, and new body plans. It is also my understanding that no scientific experiment has ever reproduced the kind of evolution that creates new novel information in DNA, new biological systems, or new body plans… but rather has only sometimes produced mutations (sometimes to the extent of irreparably damaging the DNA), has not produced a new biological system (such as a nervous system where one did not exist at all previously), and has not produced a new body plan (only modified slightly in response to environmental pressures… ex. Darwin’s finches). Being that we cannot reproduce taking a one-celled bacterium and through the unguided process of random mutations being acted upon by natural selection, and ending up with a multi-celled complex organism that no longer functions on the same order as the original (whether in a single leap or a succession of many incremental steps – reference the E.Coli experiment – after 60,000+ generations E.Coli is still just E.Coli, just adapted to survive on citrate [which resulted from a loss of function that previously existed]), I’m having trouble finding this fits with what I would consider “overwhelming” evidence. On strictly scientific grounds alone, I am not convinced that all life had a universal common ancestor… that the microbe that made you and me also made an oak tree.
Evolution and religion differ widely on the question of origins evolution of universe is based on empirical evidence in the lab while the creationist have scared book the holywrite where it contents where conveyed through advocates by higher being God
Darwin and His Theory of Evolution
At first glance, Charles Darwin seems an unlikely revolutionary. Growing up a shy and unassuming member of a wealthy British family, he appeared, at least to his father, to be idle and directionless. But even as a child, Darwin expressed an interest in nature. Later, while studying botany at Cambridge University, he was offered a chance to work as an unpaid naturalist on the HMS Beagle, a naval vessel embarking on an exploratory voyage around the world. In the course of nearly five years at sea – during which time the Beagle surveyed the coast of South America and stopped in such places as Australia and, most famously, the Galapagos Islands – Darwin took advantage of countless opportunities to observe plant and animal life and to collect both living and fossilized specimens for later study.
After the Beagle returned to England in October 1836, Darwin began reflecting on his observations and experiences, and over the next two years developed the basic outline of his groundbreaking theory of evolution through natural selection. But beyond sharing his ideas with a close circle of scientist friends, Darwin told no one of his views on the origin and development of life. Indeed, he did not publish his now-famous volume, On the Origin of Species by Means of Natural Selection, until 1859, more than 20 years after he had first formulated his theory.
On the Origin of Species may never have been written, let alone published, if it had not been for Alfred Russel Wallace, another British naturalist who independently proposed a strikingly similar theory in 1858. Wallace’s announcement prompted Darwin to publicly reveal that his own research had led him to the same conclusion decades earlier. This being the age of Victorian gentlemen, it was agreed that the two scientists would jointly publish their writings on the subject. Their work – comprising a collection of Darwin’s earlier notes and an essay by Wallace – was read to the Linnean Society, an association of naturalists, in London on July 1, 1858. The following year, Darwin published On the Origin of Species, a lengthy, fleshed-out treatment of his ideas on evolutionary theory. The book was an immediate bestseller and quickly set off a firestorm of controversy.
Darwin had expected no less – fear of a backlash from Britain’s religious and even scientific establishment had been the primary reason he had delayed publicizing his ideas. Yet the concept of species adaptation was not so radical at the time. Scientists had been debating whether animals evolved decades before Darwin put forth his theory. The idea of “transmutation of species” had been rejected by many prominent naturalists, among them French scientist Georges Cuvier, who believed that species had been created much as they appeared in his day. But transmutation also had early champions, including Darwin’s grandfather, the famed Birmingham physician Erasmus Darwin.
The younger Darwin’s achievement was to offer a plausible and compelling explanation for how species evolve and to use this explanation to trace the history of life’s development. All existing creatures, he argued, descended from a small number of original or progenitor species. Darwin compared the history of life to a great tree, its trunk representing these few common ancestors and an extensive system of branches and twigs symbolizing the great variety of life that has evolved from them.
This evolution, Darwin wrote, is due to two factors. The first factor, Darwin argued, is that each individual animal is marked by subtle differences that distinguish it from its parents. Darwin, who called these differences “variations,” understood their effect but not their cause the idea of genetic mutation, and indeed the scientific study of genetics, would not arise fully until the early 20th century. The second factor, Darwin argued, is that although variations are random, some of them convey distinct advantages – superior camouflage, a heartier constitution or greater speed, for example – that better equip a creature to survive in its environment. A greater chance of survival allows for more opportunity to breed and pass on advantageous traits to a greater number of offspring. Over time, an advantage spreads throughout a species in turn, the species is more likely to endure and reproduce. Thus, over the course of many generations, subtle changes occur and accumulate, eventually morphing into bigger changes and, possibly, even a new species.
While Darwin’s ideas initially challenged long-held scientific and religious belief systems, opposition to much of Darwin’s thinking among the scientific communities of the English-speaking world largely collapsed in the decades following the publication of On the Origin of Species. Yet evolution continued to be vigorously rejected by British and American churches because, religious leaders argued, the theory directly contradicted many of the core teachings of the Christian faith.
Darwin’s notion that existing species, including man, had developed over time due to constant and random change seemed to be in clear opposition to the idea that all creatures had been created “according to their kind” by God, as described in the first chapter of the biblical book of Genesis. Before Darwin, the prevailing scientific theory of life’s origins and development had held that species were fixed and that they never changed. This theory, known as “special creationism,” comported well with the biblical account of God creating the fish, fowl and mammals without mention of subsequent alteration.
Darwinian thinking also appeared to contradict the notion, central to Christianity and many other faiths, that man had a special, God-given place in the natural order. Instead, proponents of evolution pointed to signs in human anatomy – remnants of a tailbone, for instance – showing common ancestry with other mammals.
Finally, the idea of a benevolent God who cared for his creation was seemingly challenged by Darwin’s depiction of the natural world as a savage and cruel place – “red in tooth and claw,” as Darwin’s contemporary, Alfred Lord Tennyson, wrote just a few years before On the Origin of Species was published. Darwin’s theory challenged the idea that the natural world existed in benevolent harmony.
Darwin fully understood, and at times agonized over, the threat that his work might pose to traditional religious belief, explaining in an 1860 letter to American botanist Asa Gray that he “had no intention to write atheistically.” But, he went on, “I cannot see as plainly as others do … evidence of design and beneficence on all sides of us. There seems to be too much misery in the world.”
Regardless of his intentions, Darwin’s ideas provoked a harsh and immediate response from religious leaders in Britain. For instance, England’s highest-ranking Catholic official, Henry Cardinal Manning, denounced Darwin’s views as “a brutal philosophy – to wit, there is no God, and the ape is our Adam.” Samuel Wilberforce, the Anglican Archbishop of Oxford and one of the most highly respected religious leaders in 19th-century England, also condemned natural selection in a now-famous speech on what he deemed the theory’s scientific deficiencies at an 1860 meeting of the British Association for the Advancement of Science. At one point during the meeting, Wilberforce reportedly asked biologist Thomas Henry Huxley whether he was related to an ape on his grandmother’s or grandfather’s side. Huxley, whose vigorous defense of evolutionary theory would earn him the nickname “Darwin’s bulldog,” allegedly replied that he would rather be the ancestor of a monkey than an advanced and intelligent human being who employed his “knowledge and eloquence in misrepresenting those who are wearing out their lives in the search for truth.”
Some scholars now contend that Huxley’s rebuke of Wilberforce never occurred. Regardless, it was around this time that the British scientific establishment gained the upper hand in the debate over evolution. And while the public disagreement between ecclesiastical and scientific authorities did not end in the 1860s, religious thinkers became more wary of directly challenging evolution on scientific grounds. In the late 19th and early 20th centuries, churches instead focused much of their energy on resisting the idea that man had evolved from lower animal orders and hence had no special place in creation or, for that matter, a soul. Indeed, while some churches, including the Catholic Church, eventually accepted evolution as a God-directed mechanism of biological development, none questioned the role of God as the sole creator of man.
By the time of his death, in 1882, Darwin was considered the greatest scientist of his age. Moreover, the very church his theory had challenged accorded him a full state funeral and burial in Westminster Abbey, near the grave of Sir Isaac Newton. Darwin’s idea was still provocative, but by the time of his death it had gained general acceptance in Britain, even among many in the Anglican clergy. Indeed, his interment in the abbey was seen by some contemporaries as symbolic of an uneasy truce between science and religion in Britain.
This report was written by David Masci, a senior researcher at the Pew Research Center’s Religion & Public Life Project.
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Killers? Hippies? Toolmakers? Chefs? Scientists have trouble agreeing on the essence of humanity—and when and how we acquired it.
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What a piece of work is man! Everyone agrees on that much. But what exactly is it about Homo sapiens that makes us unique among animals, let alone apes, and when and how did our ancestors acquire that certain something? The past century has seen a profusion of theories. Some reveal as much about the time their proponents lived in as they do about human evolution.
1. We Make Tools: “It is in making tools that man is unique,” anthropologist Kenneth Oakley wrote in a 1944 article. Apes use found objects as tools, he explained, “but the shaping of sticks and stones to particular uses was the first recognizably human activity.” In the early 1960s, Louis Leakey attributed the dawn of toolmaking, and thus of humanity, to a species named Homo habilis (“Handy Man”), which lived in East Africa around 2.8 million years ago. But as Jane Goodall and other researchers have since shown, chimps also shape sticks for particular uses—stripping them of their leaves, for instance, to “fish” for underground insects. Even crows, which lack hands, are pretty handy.
2. We’re Killers: According to anthropologist Raymond Dart, our predecessors differed from living apes in being confirmed killers—carnivorous creatures that "seized living quarries by violence, battered them to death, tore apart their broken bodies, dismembered them limb from limb, slaking their ravenous thirst with the hot blood of victims and greedily devouring livid writhing flesh.” It may read like pulp fiction now, but after the horrific carnage of the Second World War, Dart’s 1953 article outlining his “killer ape” theory struck a chord.
3. We Share Food: In the 1960s, the killer ape gave way to the hippie ape. Anthropologist Glynn Isaac unearthed evidence of animal carcasses that had been purposefully moved from the sites of their deaths to locations where, presumably, the meat could be shared with the whole commune. As Isaac saw it, food sharing led to the need to share information about where food could be found—and thus to the development of language and other distinctively human social behaviors.
4. We Swim in the Nude: A little later in the age of Aquarius, Elaine Morgan, a TV documentary writer, claimed that humans are so different from other primates because our ancestors evolved in a different environment—near and in the water. Shedding body hair made them faster swimmers, while standing upright enabled them to wade. The “aquatic ape” hypothesis is widely dismissed by the scientific community. But, in 2013, David Attenborough endorsed it.
5. We Throw Stuff: Archaeologist Reid Ferring believes our ancestors began to man up when they developed the ability to hurl stones at high velocities. At Dmanisi, a 1.8- million-year-old hominin site in the former Soviet republic of Georgia, Ferring found evidence that Homo erectus invented public stonings to drive predators away from their kills. “The Dmanisi people were small,” says Ferring.“This place was filled with big cats. So how did hominins survive? How did they make it all the way from Africa? Rock throwing offers part of the answer.” Stoning animals also socialized us, he argues, because it required a group effort to be successful.
6. We Hunt: Hunting did much more than inspire cooperation, anthropologists Sherwood Washburn and C. S. Lancaster argued in a 1968 paper: “In a very real sense our intellect, interests, emotions and basic social life—all are evolutionary products of the success of the hunting adaptation.” Our larger brains, for instance, developed out of the need to store more information about where and when to find game. Hunting also allegedly led to a division of labor between the sexes, with women doing the foraging. Which raises the question: Why do women have big brains too?
7. We Trade Food for Sex: More specifically, monogamous sex. The crucial turning point in human evolution, according to a theory published in 1981 by C. Owen Lovejoy, was the emergence of monogamy six million years ago. Until then, brutish alpha males who drove off rival suitors had the most sex. Monogamous females, however, favored males who were most adept at providing food and sticking around to help raise junior. Our ancestors began walking upright, according to Lovejoy, because it freed up their hands and allowed them to carry home more groceries.
8. We Eat (Cooked) Meat: Big brains are hungry—gray matter requires 20 times more energy than muscle does. They could never have evolved on a vegetarian diet, some researchers claim instead, our brains grew only once we started eating meat, a food source rich in protein and fat, around two to three million years ago. And according to anthropologist Richard Wrangham, once our ancestors invented cooking—a uniquely human behavior that makes food easier to digest—they wasted less energy chewing or pounding meat and so had even more energy available for their brains. Eventually those brains grew large enough to make the conscious decision to become vegan.
9. We Eat (Cooked) Carbs: Or maybe our bigger brains were made possible by carb-loading, according to a recent paper. Once our ancestors had invented cooking, tubers and other starchy plants became an excellent source of brain food, more readily available than meat. An enzyme in our saliva called amylase helps break down carbohydrates into the glucose the brain needs. Evolutionary geneticist Mark G. Thomas of University College London notes that our DNA contains multiple copies of the gene for amylase, suggesting that it—and tubers—helped fuel the explosive growth of the human brain.
10. We Walk on Two Feet: Did the crucial turning point in human evolution occur when our ancestors descended from the trees and started walking upright? Proponents of the “savanna hypothesis” say climate change drove that adaptation. As Africa became drier around three million years ago, the forests shrank and savannas came to dominate the landscape. That favored primates who could stand up and see above the tall grasses to watch for predators, and who could travel more efficiently across the open landscape, where food and water sources were far apart. One problem for this hypothesis is the 2009 discovery of Ardipithecus ramidus, a hominid that lived 4.4 million years ago in what’s now Ethiopia. That region was damp and wooded then—yet “Ardi” could walk on two legs.