We are searching data for your request:
Upon completion, a link will appear to access the found materials.
Discuss the history of the study of life
The history of biology traces the study of the living world from ancient to modern times. Although the concept of biology as a single coherent field arose in the nineteenth century, the biological sciences emerged from traditions of medicine and natural history reaching back to ayurveda, ancient Egyptian medicine and the works of Aristotle and Galen in the ancient Greco-Roman world. This ancient work was further developed in the Middle Ages by Muslim physicians and scholars such as Avicenna. During the European Renaissance and early modern period, biological thought was revolutionized in Europe by a renewed interest in empiricism and the discovery of many novel organisms. Prominent in this movement were Vesalius and Harvey, who used experimentation and careful observation in physiology, and naturalists such as Linnaeus and Buffon who began to classify the diversity of life and the fossil record, as well as the development and behavior of organisms. Antonie van Leeuwenhoek revealed by means of microscopy the previously unknown world of microorganisms, laying the groundwork for cell theory. The growing importance of natural theology, partly a response to the rise of mechanical philosophy, encouraged the growth of natural history.
Over the eighteenth and nineteenth centuries, biological sciences such as botany and zoology became increasingly professional scientific disciplines. Lavoisier and other physical scientists began to connect the animate and inanimate worlds through physics and chemistry. Explorer-naturalists such as Alexander von Humboldt investigated the interaction between organisms and their environment, and the ways this relationship depends on geography—laying the foundations for biogeography, ecology, and ethology. Naturalists began to reject essentialism and consider the importance of extinction and the mutability of species. Cell theory provided a new perspective on the fundamental basis of life. These developments, as well as the results from embryology and paleontology, were synthesized in Charles Darwin’s theory of evolution by natural selection. The end of the 19th century saw the fall of spontaneous generation and the rise of the germ theory of disease, though the mechanism of inheritance remained a mystery.
In the early twentieth century, the rediscovery of Gregor Mendel’s work led to the rapid development of genetics by Thomas Hunt Morgan and his students, and by the 1930s the combination of population genetics and natural selection in the “neo-Darwinian synthesis”. New disciplines developed rapidly, especially after James Watson and Francis Crick proposed the structure of DNA. Following the establishment of the Central Dogma and the cracking of the genetic code, biology was largely split between organismal biology—the fields that deal with whole organisms and groups of organisms—and the fields related to cellular and molecular biology. By the late twentieth century, new fields like genomics and proteomics were reversing this trend, with organismal biologists using molecular techniques, and molecular and cell biologists investigating the interplay between genes and the environment, as well as the genetics of natural populations of organisms.
Mechanisms of salinity tolerance
The physiological and molecular mechanisms of tolerance to osmotic and ionic components of salinity stress are reviewed at the cellular, organ, and whole-plant level. Plant growth responds to salinity in two phases: a rapid, osmotic phase that inhibits growth of young leaves, and a slower, ionic phase that accelerates senescence of mature leaves. Plant adaptations to salinity are of three distinct types: osmotic stress tolerance, Na(+) or Cl() exclusion, and the tolerance of tissue to accumulated Na(+) or Cl(). Our understanding of the role of the HKT gene family in Na(+) exclusion from leaves is increasing, as is the understanding of the molecular bases for many other transport processes at the cellular level. However, we have a limited molecular understanding of the overall control of Na(+) accumulation and of osmotic stress tolerance at the whole-plant level. Molecular genetics and functional genomics provide a new opportunity to synthesize molecular and physiological knowledge to improve the salinity tolerance of plants relevant to food production and environmental sustainability.
18.104.22.168: The History of Biology - Biology
The Biology of Skin Color: Black and White
The evolution of race was as simple as the politics of race is complex
By Gina Kirchweger
Ten years ago, while at the university of Western Australia, anthropologist Nina Jablonski was asked to give a lecture on human skin. As an expert in primate evolution, she decided to discuss the evolution of skin color, but when she went through the literature on the subject she was dismayed. Some theories advanced before the 1970s tended to be racist, and others were less than convincing. White skin, for example, was reported to be more resistant to cold weather, although groups like the Inuit are both dark and particularly resistant to cold. After the 1970s, when researchers were presumably more aware of the controversy such studies could kick up, there was very little work at all. "It's one of these things everybody notices," Jablonski says, "but nobody wants to talk about."
No longer. Jablonski and her husband, George Chaplin, a geographic information systems specialist, have formulated the first comprehensive theory of skin color. Their findings, published in a recent issue of the Journal of Human Evolution, show a strong, somewhat predictable correlation between skin color and the strength of sunlight across the globe. But they also show a deeper, more surprising process at work: Skin color, they say, is largely a matter of vitamins.
Jablonski, now chairman of the anthropology department at the California Academy of Sciences, begins by assuming that our earliest ancestors had fair skin just like chimpanzees, our closest biological relatives. Between 4.5 million and 2 million years ago, early humans moved from the rain forest and onto the East African savanna. Once on the savanna, they not only had to cope with more exposure to the sun, but they also had to work harder to gather food. Mammalian brains are particularly vulnerable to overheating: A change of only five or six degrees can cause a heatstroke. So our ancestors had to develop a better cooling system.
The answer was sweat, which dissipates heat through evaporation. Early humans probably had few sweat glands, like chimpanzees, and those were mainly located on the palms of their hands and the bottoms of their feet. Occasionally, however, individuals were born with more glands than usual. The more they could sweat, the longer they could forage before the heat forced them back into the shade. The more they could forage, the better their chances of having healthy offspring and of passing on their sweat glands to future generations.
A million years of natural selection later, each human has about 2 million sweat glands spread across his or her body. Human skin, being less hairy than chimpanzee skin, "dries much quicker," says Adrienne Zihlman, an anthropologist at the University of California at Santa Cruz. "Just think how after a bath it takes much longer for wet hair to dry."
Hairless skin, however, is particularly vulnerable to damage from sunlight. Scientists long assumed that humans evolved melanin, the main determinant of skin color, to absorb or disperse ultraviolet light. But what is it about ultraviolet light that melanin protects against? Some researchers pointed to the threat of skin cancer. But cancer usually develops late in life, after a person has already reproduced. Others suggested that sunburned nipples would have hampered breast-feeding. But a slight tan is enough to protect mothers against that problem.
During her preparation for the lecture in Australia, Jablonski found a 1978 study that examined the effects of ultraviolet light on folate, a member of the vitamin B complex. An hour of intense sunlight, the study showed, is enough to cut folate levels in half if your skin is light. Jablonski made the next, crucial connection only a few weeks later. At a seminar on embryonic development, she heard that low folate levels are correlated with neural-tube defects such as spina bifida and anencephaly, in which infants are born without a full brain or spinal cord.
Jablonski and Chaplin predicted the skin colors of indigenous people across the globe based on how much ultraviolet light different areas receive. Graphic by Matt Zang, adapted from the data of N. Jablonski and G. Chaplin
Jablonski later came across three documented cases in which children's neural-tube defects were linked to their mothers' visits to tanning studios during early pregnancy. Moreover, she found that folate is crucial to sperm development -- so much so that a folate inhibitor was developed as a male contraceptive. ("It never got anywhere," Jablonski says. "It was so effective that it knocked out all folate in the body.") She now had some intriguing evidence that folate might be the driving force behind the evolution of darker skin. But why do some people have light skin?
As far back as the 1960s, the biochemist W. Farnsworth Loomis had suggested that skin color is determined by the body's need for vitamin D. The vitamin helps the body absorb calcium and deposit it in bones, an essential function, particularly in fast-growing embryos. (The need for vitamin D during pregnancy may explain why women around the globe tend to have lighter skin than men.) Unlike folate, vitamin D depends on ultraviolet light for its production in the body. Loomis believed that people who live in the north, where daylight is weakest, evolved fair skin to help absorb more ultraviolet light and that people in the tropics evolved dark skin to block the light, keeping the body from overdosing on vitamin D, which can be toxic at high concentrations.
By the time Jablonski did her research, Loomis's hypothesis had been partially disproved. "You can never overdose on natural amounts of vitamin D," Jablonski says. "There are only rare cases where people take too many cod-liver supplements." But Loomis's insight about fair skin held up, and it made a perfect complement for Jablonski's insight about folate and dark skin. The next step was to find some hard data correlating skin color to light levels.
Until the 1980s, researchers could only estimate how much ultraviolet radiation reaches Earth's surface. But in 1978, NASA launched the Total Ozone Mapping Spectrometer. Three years ago, Jablonski and Chaplin took the spectrometer's global ultraviolet measurements and compared them with published data on skin color in indigenous populations from more than 50 countries. To their delight, there was an unmistakable correlation: The weaker the ultraviolet light, the fairer the skin. Jablonski went on to show that people living above 50 degrees latitude have the highest risk of vitamin D deficiency. "This was one of the last barriers in the history of human settlement," Jablonski says. "Only after humans learned fishing, and therefore had access to food rich in vitamin D, could they settle these regions."
Humans have spent most of their history moving around. To do that, they've had to adapt their tools, clothes, housing, and eating habits to each new climate and landscape. But Jablonski's work indicates that our adaptations go much further. People in the tropics have developed dark skin to block out the sun and protect their body's folate reserves. People far from the equator have developed fair skin to drink in the sun and produce adequate amounts of vitamin D during the long winter months.
Jablonski hopes that her research will alert people to the importance of vitamin D and folate in their diet. It's already known, for example, that dark-skinned people who move to cloudy climes can develop conditions such as rickets from vitamin D deficiencies. More important, Jablonski hopes her work will begin to change the way people think about skin color. "We can take a topic that has caused so much disagreement, so much suffering, and so much misunderstanding," she says, "and completely disarm it."
(From Discover, Vol. 22, No. 2, February, 2001. Gina Kirchweger © 2001. Reprinted with permission of Discover. )
Focused on the life sciences
In the Department of Biological Sciences, you will find game-changing discoveries and life-changing education, from the molecular to ecosystem levels. We are focused on some of the toughest challenges of our time - fighting cancer, combating infectious diseases, unraveling climate change, and dissecting how we see, hear and interact with our surroundings. Our research and scholarship changes people's lives and the planet.
Studying and working within our welcoming community of life scientists can be the first step to changing your life. You'll find that research and academic pursuits are interwoven as faculty create and share new knowledge.
Research in the Department of Biological Science contributes to developing personalized medicine, unraveling how the human brain functions, combating infectious diseases, understanding genomes at levels never before imagined, and understanding the complex ecosystems that keep our planet healthy. We are responsive to challenges that appear suddenly and need immediate attention – because we prepare persistently for the moments when our knowledge can lead the way.
We are the largest department in the life sciences at Purdue University with degree-granting programs that cover the breadth of biology:
We believe that STEM education and careers should be inclusive and accessible. We are deeply committed to mentoring our students and helping them apply their knowledge and develop the skills needed to become leaders in the scientific workforce.
As part of the College of Science, we have capacity for cross-disciplinary partnerships that encourage undergraduate research experiences and empower graduate students who work and publish with renowned faculty. The diverse nature of biological sciences lends itself to collaborations in the physical sciences, agriculture, engineering, education and computational sciences. Partnerships abound as researchers from across campus work together to solve today's toughest challenges.
University Response to the COVID-19 Pandemic
The University continues to closely monitor the spread of COVID-19, also known as the coronavirus, as additional cases are confirmed in the United States and other countries. The University continues to formulate and adjust its plans as needed.
Transition to Workday - July 1, 2021
Workday is Howard's new system to manage HR and financial processes. On July 1, 2021, it will go live and replace all existing systems.
STATEMENT FROM THE DEPARTMENT CHAIR
Above, you have heard from our faculty about who the department is, what we believe in, and the values that we will expect and uphold. We affirm the Seahawk Respect Compact, actively fostering, encouraging, and promoting inclusiveness, mutual respect, acceptance, and open-mindedness among students, faculty, staff and the broader community. Most importantly, we are committed to an environment of respect for all individuals in our department community: students, staff, and faculty.
I stand with them, and with all of you.
I also want you to know that we stand behind our words: we are taking action to make change. These plans are evolving but will include self-reflection and accounting at the department level, training and workshops, and the creation of a committee of members of the department community to help move us forward with our charge to enhance diversity, inclusion, and equity. But the first step is to hear from you. I am going to host a Town Hall style forum at the beginning of the Fall 2020 semester, in which we can share and discuss ideas so that all of us can shape the future of our department.
We believe in you, and we are here for you.
Itasca Biological Station and Laboratories
“There can be no peace without justice.” - Reverend Dr. Martin Luther King Jr. The Itasca Biological Station and Labs is committed to being part of the solution. Link here for resources to support your communities in this critical time of change.
2021 Graduate Research Fellowship submissions are now open.
Field courses are planned to be in person this May, with scholarships available. Go to this link to apply.
COVID-19 Update (Spring Semester 2021): Following guidance from the University, we continue to be under reduced operations and will be through the end of this semester, at which point we will re-evaluate based on guidance at that time. This means only approved essential researchers/employees can use Itasca facilities with 1 person per cabin. Our top priority remains the health, safety, and wellbeing of our University and Itasca communities. If you have questions, contact us at . Researchers looking for creative ideas to generate data? We at Itasca have these resources to enable new research ideas.
We were recently featured on Common Ground PBS on Lakeland PBS - click here to view the full episode!
Department of Biology
We are committed to providing excellent and comprehensive instruction at undergraduate and graduate levels in environmental health science, ecology, evolution and cell and molecular biology.
Recent Faculty Research
In The News
Success During the Pandemic
The UNCG Department of Biology has a plan to support your success during the pandemic. Jump To: Courses offered [&hellip]
Diversity, equity, and inclusion
The faculty and staff of the UNCG Department of Biology recognize that systemic racism, racist behaviors, and gender biased policies [&hellip]
A message from the Head
Dear Colleagues, Like all of you, I have been watching the impact of centuries of racism and violence against BIPOC in [&hellip]
Faculty Spotlight: Dr. Sally Koerner
Dr. Sally Koerner is a 2019 Bernard Glickman Dean’s Professor, an honor bestowed on an Assistant Professor in recognition of [&hellip]
Posted on December 21, 2020
Ann Somers: An educator, a scientist, an inspiration
This fall we are celebrating the retirement of Ms. Ann Somers after 31 years of service to UNCG. Ann will be [&hellip]
Posted on December 18, 2020
Welcome to our newest faculty member
Dr. Jim Coleman Provost & Executive Vice Chancellor and Professor of Biology Provost Coleman joined the UNCG Department of Biology [&hellip]
Posted on December 18, 2020
No upcoming seminars at this time.
Jenessa Gjeltema, DVM, Dipl. ACZM is currently an Assistant Professor of Zoological Medicine at the University of California, Davis, School of Veterinary Medicine.
Join Our Google Groups!
For advising questions please contact your advisor. If you do not have an advisor please call our office at 336-334-5391 or email us at [email protected]
For add/drop and override requests please contact the instructor of each course.
Interested in a pre-professional program? Contact Professor Robin Maxwell, Director of our Pre-med Post-Baccalaureate program, at [email protected]
New Core Requirements for Biology Majors
Please click here for the list of new requirements for Biology majors. This list applies to ALL current Biology majors.
The Department of Biology
By Phone: 8am-5pm
Virtual: by appointment
312 Eberhart Building
321 McIver Street
Greensboro, NC 27412
Great things are happening at Museum of Southwestern Biology!
UNM’s new graduate training program, Museum Research Traineeship (MRT) is accepting applicants! The program is designed around leveraging the collections of the MSB — and other UNM science museums — to conduct innovative, trans-disciplinary science. Applications will be processed through the participating departments: Biology, Anthropology, Earth and Planetary Sciences, and Geography and Environmental Science. Please find more information on the program’s new webpage: Museum Research Traineeship
For a general background on our museum, please watch our introduction video here
In March, 2020, Covid-19 access restrictions to the MSB began. We reopened to students and research associates on a very limited basis beginning in July, 2020. The MSB remains largely closed to outside visitors, but research and curation activities continue. Staff and faculty of the MSB are working within policies set by UNM and the State of New Mexico to continue their important work documenting biodiversity, training students, conducting research, and curating collections.
Our hard-working collection managers are making sure that our facilities and collections are secured and that all personnel are following physical distancing and masks policies. All occupants of the CERIA Building, where MSB is housed, are following strict standard operating procedures to maintain low density in shared spaces, and maximize hygiene in order to reduce the chances that any transmission of SARS-CoV-2 will occur.
Meanwhile, staff, curators, students, volunteers, and research associates are working from home as much as possible on digital data curation, data analyses, scientific manuscripts, and grant proposals. New Mexico based field-work is proceeding, while following all appropriate safety guidelines to prevent transmission of SARS CoV-2.
Many exciting publications by our personnel or based on our collections are coming out. Check out the latest ones here:
Latest Premium Content
If you are a student then the summertime is a very important time of year for you. After all, you look forward to it months in advance! The thing is, however, that in addition to having some fun you can also get ahead by making some good choices as it pertains to your employment. The summer is a great time of year for students to learn some new skills as well as make some money for the future. The bottom line is that this time of year goes by quickly- you need to plan your job in advance.
Despite the fact that my most recent post on course-notes.org discussed reasons "why the infamous all-nighter is a terrible idea," I would like to share some advice for those of you that will, without a doubt, pull numerous all-nighters in the coming years.
So you're procrastinator. The good news, so are millions of high school and college students across the country. By all accounts, you're not unique in your inability to get ahead on assignments and more often than not, you'll be "forced" to stay up late either cramming for an exam or attempting to complete a six page paper you were assigned more than a month ago.
While it's been years since I graduated high school back in 2007, my first-hand experience with the college application process remains vivid in my mind. Between the AP courses/tests, taking the SAT/ACT and the pressures to maintain a competitive GPA, the life of an ambitious high schooler is no doubt, stressful. In the years since I was accepted into College, acceptance rates (on average) have continued to decline. In 2012, my alma mater had an admission rate of only 12.4%.
My name is Daniel Black and I graduated from Claremont McKenna College in May of 2011 as a dual-major in Economics and Government. I was fortunate enough to spend time working as a "Senior Interviewer" for the Admissions Office which provided me with the opportunity to interview a large number of prospective students. I know what colleges look for (and what turns them off), but more importantly, what steps you can take to distinguish yourself from the crowd.
When it comes to back to school shopping for freshman students there's no need to make a list with the obvious items like notebooks, pencils, erasers and pens. You probably have a whole drawer stuffed full of school supplies like those that you can re-use. Within this article we'll be mentioning 5 supplies every freshman student should buy and we want you to focus on items that might not have immediately come to mind. If you can't think of any off of the top of your head then all you have to do is read the rest of article to find out what they are!