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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.”

Evolution of Man 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?

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.

Making sense of ancient hominin DNA Resource library : Evo in the news : Making sense of ancient hominin DNAMay 2010, update added in July 2010 In the last two months, news outlets have been abuzz with the announcement of what many suggested was a new hominin species. In 2008, a 40,000 year old pinky bone from a child was discovered in a Siberian cave. The bone was not enough to identify the species of its possessor, but since both Neanderthals and humans are known to have lived in the area at the time, scientists assumed it belonged to one of these two species. Where's the evolution? Based on the sequences of mitochondrial DNA extracted from the pinky bone, Neanderthal fossils, and modern humans, the researchers built a phylogenetic tree that shows how all the different sequences are likely related to each other and how recently they descended from a common ancestor. If the mitochondrial gene tree turns out to be an accurate indicator of species relationships, it might indeed mean that X-woman is a new species. Green, R.

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

Darwin's Finches (Natural Selection) 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.

New Year Brings New Attacks on Evolution in Schools | New Hampshire & Indiana Evolution Proposals | HB 1148, HB 1457 & SB 89 | Evolution in Public Schools The new year is bringing new controversy over teaching evolution in public schools, with two bills in New Hampshire seeking to require teachers to teach the theory more as philosophy than science. Meanwhile, an Indiana state senator has introduced a bill that would allow school boards to require the teaching of creationism. New Hampshire House Bill 1148 would "require evolution to be taught in the public schools of this state as a theory, including the theorists' political and ideological viewpoints and their position on the concept of atheism." The second proposal in the New Hampshire House, HB 1457, does not mention evolution specifically but would "require science teachers to instruct pupils that proper scientific inquire [sic] results from not committing to any one theory or hypothesis, no matter how firmly it appears to be established, and that scientific and technological innovations based on new evidence can challenge accepted scientific theories or modes." Religion and science

Random Genetic Drift Random Genetic Drift Copyright © 1993-1997 by Laurence Moran[Last Update: January 22, 1993] he two most important mechanisms of evolution are natural selection and genetic drift. Most people have a reasonable understanding of natural selection but they don't realize that drift is also important. The anti- evolutionists, in particular, concentrate their attack on natural selection not realizing that there is much more to evolution. Random genetic drift is a stochastic process (by definition). Suzuki et al. explain it as well as anyone I've seen; "If a population is finite in size (as all populations are) and if a given pair of parents have only a small number of offspring, then even in the absence of all selective forces, the frequency of a gene will not be exactly reproduced in the next generation because of sampling error. Of course random genetic drift is not limited to species that have few offspring, such as humans. But random genetic drift is even more that this. And:

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

Definition of Scientific Theory Creationists argue that evolution is "only a theory and cannot be proven." As used in science, a theory is an explanation or model based on observation, experimentation, and reasoning, especially one that has been tested and confirmed as a general principle helping to explain and predict natural phenomena. Any scientific theory must be based on a careful and rational examination of the facts. A clear distinction needs to be made between facts (things which can be observed and/or measured) and theories (explanations which correlate and interpret the facts. A fact is something that is supported by unmistakeable evidence. It is a fact is that fossil skulls have been found that are intermediate in appearance between humans and modern apes. Facts may be interpreted in different ways by different individuals, but that doesn't change the facts themselves. Theories may be good, bad, or indifferent.

Science/Nature | Oldest human skulls found Three fossilised skulls unearthed in Ethiopia are said by scientists to be among the most important discoveries ever made in the search for the origin of humans. The crania of two adults and a child, all dated to be around 160,000 years old, were pulled out of sediments near a village called Herto in the Afar region in the east of the country. They are described as the oldest known fossils of modern humans, or Homo sapiens. What excites scientists so much is that the specimens fit neatly with the genetic studies that have suggested this time and part of Africa for the emergence of mankind. "All the genetics have pointed to a geologically recent origin for humans in Africa - and now we have the fossils," said Professor Tim White, one of the co-leaders on the research team that found the skulls. Out of Africa The skulls are not an exact match to those of people living today; they are slightly larger, longer and have more pronounced brow ridges. Sophisticated behaviour

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