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Introduction to Evolutionary Biology

Introduction to Evolutionary Biology
Introduction to Evolutionary Biology Version 2 Copyright © 1996-1997 by Chris Colby[Last Update: January 7, 1996] volution is the cornerstone of modern biology. It unites all the fields of biology under one theoretical umbrella. It is not a difficult concept, but very few people -- the majority of biologists included -- have a satisfactory grasp of it. One common mistake is believing that species can be arranged on an evolutionary ladder from bacteria through "lower" animals, to "higher" animals and, finally, up to man. Mistakes permeate popular science expositions of evolutionary biology. Misunderstandings about evolution are damaging to the study of evolution and biology as a whole. This is a brief introduction to evolutionary biology. What is Evolution? Evolution is a change in the gene pool of a population over time. The English moth, Biston betularia, is a frequently cited example of observed evolution. Populations evolve. The word evolution has a variety of meanings.

Top 10 Myths About Evolution – with Downloadable PDF | Atheism Resource Email If you have been looking for a simple, easy to follow quick guide to evolution… we’ve got it. Our friends at the Skeptics Society gave us permission to reprint this. Below is the text. Learn it. Original Text: 1 If Humans Came From Apes, Why Aren’t Apes Evolving Into Humans? Humans, apes, and monkeys are only distant evolutionary “cousins.” 2 There Are Too Many Gaps in the Fossil Record for Evolution to Be True In fact, there are lots of intermediate fossils. 3 If Evolution Happened Gradually Over Millions of Years Why Doesn’t the Fossil Record Show Gradual Change? Sudden changes in the fossil record are not missing evidence of gradualism; they are extant evidence of punctuation. 4 No One Has Ever Seen Evolution Happen Evolution is a historical science confirmed by the fact that so many independent lines of evidence converge to this single conclusion. 5 Science Claims That Evolution Happens by Random Chance Natural selection is not “random” nor does it operate by “chance.”

Scientists Uncover How Dainty Rhino Feet Support Huge Bodies | Despite Their Portliness, Rhinos' Feet Take It All in Stride | Rhinoceros Feet Explained How do rhinos' dainty little pigeon-toed feet support their portly bodies? A group of veterinary scientists in the United Kingdom are on the case. By coaxing three white rhinos to walk back and forth across a "pressure pad," a floor mat embedded with thousands of pressure sensors, the researchers are collecting data on how much force the beasts exert on different parts of their feet as they walk. A rhinoceros can weigh as much as 8,000 pounds (3,600 kilograms), yet somehow, their feet manage to take all those tons in stride. Initial results show that, with each step, their toes feel peak pressures of 75 pounds per square inch (psi), and the pads of their feet, 15 psi. That's not so much. White rhinos in Namibia.Credit: Ikiwaner | Creative Commons In addition to figuring out how rhino feet manage this feat, the scientists are investigating how the beasts' locomotion differs from that of other large land mammals — in particular, elephants. For that matter, should anyone?

Human Evolution & Archaeology 100 Time-Saving Search Engines for Serious Scholars While burying yourself in the stacks at the library is one way to get some serious research done, with today’s technology you can do quite a bit of useful searching before you ever set foot inside a library. Undergraduates and grad students alike will appreciate the usefulness of these search engines that allow them to find books, journal articles and even primary source material for whatever kind of research they’re working on and that return only serious, academic results so time isn’t wasted on unprofessional resources. Note: Visit our updated list for the latest in academic search engines. General Start off your research with one of these more general academic search engines. Intute: Use this website’s search tools to find the best and most reliable sites to start your research. Meta Search Want to search it all at once? Dogpile: Search Google, Yahoo, Bing and more at once with this great search engine. Databases and Archives Books and Journals Science Math and Technology Social Science

The Brain—Information about the Brain 1 Introduction “I think, therefore I am.” —René Descartes, 17th-century philosopher Few of us question the crucial importance of the brain. It is vital to our existence. The brain makes up only 2 percent of our body weight, but it consumes 20 percent of the oxygen we breathe and 20 percent of the energy we consume. Scientists have worked for many years to unravel the complex workings of the brain. Despite these and other significant advances in the field of brain research, most of the processes responsible for the integrated functioning of billions of brain cells remain a mystery. An essential aspect of any scientific research is communicating results to the public in a way that is easily understood. To correctly interpret the information transmitted through these venues, we need a better understanding of basic concepts related to the brain. 2 Myths and Realities about the Brain Myth: The brain is separate from the nervous system. Myth: The brain is a uniform mass of tissue. Figure 1.

Human evolution Human evolution is the evolutionary process leading up to the appearance of modern humans. While it began with the last common ancestor of all life, the topic usually covers only the evolutionary history of primates, in particular the genus Homo, and the emergence of Homo sapiens as a distinct species of hominids (or "great apes"). The study of human evolution involves many scientific disciplines, including physical anthropology, primatology, archaeology, ethology, linguistics, evolutionary psychology, embryology and genetics.[1] The earliest documented members of the genus Homo are Homo habilis which evolved around 2.3 million years ago; the earliest species for which there is positive evidence of use of stone tools. History of study[edit] Before Darwin[edit] Darwin[edit] The first debates about the nature of human evolution arose between Thomas Huxley and Richard Owen. First fossils[edit] A major problem at that time was the lack of fossil intermediaries. The East African fossils[edit]

Brain's connective cells are much more than glue: Glia cells also regulate learning and memory Glia cells, named for the Greek word for "glue," hold the brain's neurons together and protect the cells that determine our thoughts and behaviors, but scientists have long puzzled over their prominence in the activities of the brain dedicated to learning and memory. Now Tel Aviv University researchers say that glia cells are central to the brain's plasticity -- how the brain adapts, learns, and stores information. According to Ph.D. student Maurizio De Pittà of TAU's Schools of Physics and Astronomy and Electrical Engineering, glia cells do much more than hold the brain together. De Pittà's research, led by his TAU supervisor Prof. Regulating the brain's "social network" The brain is constituted of two main types of cells: neurons and glia. But Ben-Jacob and colleagues suspected that glia cells were even more central to how the brain works. The brain is like a social network, says Prof. New brain-inspired technologies and therapies

Engineered stem cells seek out and kill HIV in living mice Expanding on previous research providing proof-of-principle that human stem cells can be genetically engineered into HIV-fighting cells, a team of UCLA researchers have now demonstrated that these cells can actually attack HIV-infected cells in a living organism. The study, published April 12 in the journal PLoS Pathogens, demonstrates for the first time that engineering stem cells to form immune cells that target HIV is effective in suppressing the virus in living tissues in an animal model, said lead investigator Scott G. Kitchen, an assistant professor of medicine in the division of hematology and oncology at the David Geffen School of Medicine at UCLA and a member of the UCLA AIDS Institute. "We believe that this study lays the groundwork for the potential use of this type of an approach in combating HIV infection in infected individuals, in hopes of eradicating the virus from the body," he said.

The "Johnny Depp Effect" - An evolutionary explanation for homosexuality Who is more attractive as a mate? A guy who is kind or a guy who is cruel? A guy who is sensitive or a guy who lacks empathy ? A guy who is physically attractive or a guy who is homely? A guy who can appreciate art or the guy who only appreciates ESPN? Now consider who is more likely to be gay. This exercise in mate preferences (and stereotypes , please excuse us) serves to illustrate a simple point: Gay men are attractive. Two recent articles suggest that these women are on to something. Again, scientists have known for some time that sexual orientation has a genetic component. It was once hypothesized that such a trait could be maintained via kin selection. Hypotheses demand empirical tests, and when the kin selection hypothesis of homosexuality was tested by David Bobrow and Michael Bailey of Northwestern University and later by Qazi Rahman and Matthew Hull of the University of East London, it was not supported. References

Missing link found? Scientists unveil fossil of 47 million-year-old primate, Darwinius masillae Tama/Getty The 47 million year old fossilized remains of a primate is seen at the American Museum of Natural History in New York. Feast your eyes on what a group of scientists call the Holy Grail of human evolution. A team of researchers Tuesday unveiled an almost perfectly intact fossil of a 47 million-year-old primate they say represents the long-sought missing link between humans and apes. Officially known as Darwinius masillae, the fossil of the lemur-like creature dubbed Ida shows it had opposable thumbs like humans and fingernails instead of claws. Scientists say the cat-sized animal's hind legs offer evidence of evolutionary changes that led to primates standing upright - a breakthrough that could finally confirm Charles Darwin's theory of evolution. "This specimen is like finding the Lost Ark for archeologists," lead scientist Jorn Hurum said at a ceremony at the American Museum of Natural History. "It is the scientific equivalent of the Holy Grail. rschapiro@nydailynews.com

Loss of Predators Impacts Food Chain | Africa A loss of species at the top of the food chain could have far-reaching effects on the environment, according to a study in the Journal Science. Some of the world’s top predators - including lions, wolves and sharks - are in sharp decline. Human activities like pollution, habitat destruction, overfishing and hunting are largely to blame. Jim Estes studies sea otters. “We have discovered that sea otters have an important limiting effect on sea urchins and that allows the kelp forest to persist," he says. In the absence of sea otters, the ocean's kelp forest - which provides a habitat for fish and absorbs climate changing carbon emissions from the atmosphere - is left barren by sea urchins. The kelp forests also provide habitat for fish and absorb climate changing carbon emissions from the atmosphere. Estes compiled the work of 24 scientists in six countries. Restoration of wolves to Yellowstone National Park has allowed vegetation to recover from over-browsing by elk.

Evolution is a Fact and a Theory Copyright © 1993-2002 [Last Update: January 22, 1993] hen non-biologists talk about biological evolution they often confuse two different aspects of the definition. On the one hand there is the question of whether or not modern organisms have evolved from older ancestral organisms or whether modern species are continuing to change over time. On the other hand there are questions about the mechanism of the observed changes... how did evolution occur? Biologists consider the existence of biological evolution to be a fact. In the American vernacular, "theory" often means "imperfect fact"--part of a hierarchy of confidence running downhill from fact to theory to hypothesis to guess. Gould is stating the prevailing view of the scientific community. Let me try to make crystal clear what is established beyond reasonable doubt, and what needs further study, about evolution. Also: Today, nearly all biologists acknowledge that evolution is a fact.

365 days: 2011 in review For science — as for politics and economics — 2011 was a year of upheaval, the effects of which will reverberate for decades. The United States lost three venerable symbols of its scientific might: the space-shuttle programme, the Tevatron particle collider and blockbuster profits from the world's best-selling drug all came to an end. But the year also saw stirrings of science's future: hopes that research might blossom following the Arab Spring; cheap vaccines rolling out in Africa; and the first fruits of genome sequencing being used in the clinic. All this was overshadowed by the triple trauma of Japan's devastating earthquake, tsunami and nuclear meltdown, and a continual chipping away at science funding as nations struggled with the financial crisis. The stem-cell roller coaster It has been an emotional year for advocates and opponents of embryonic stem (ES) cell research. R. Powered down: the Tevatron collider was turned off for good in September. Puzzling over particles B. Gi.

10 Awesome Online Classes You Can Take For Free Cool, but you need iTunes for nearly everything, and that gets an 'F.' Are there really no other places to get these lessons? I was sure there are some on Academic Earth. Flagged 1. 7 of them are available via YouTube. 2. iTunes is free. 1. 2. Don't worry, we're looking out for you! While I have no personal beef with iTunes, I know that many people share your sentiments — so I actually made a concerted effort to include relevant youtube links when possible.

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