CTD Posted October 20, 2009 Author Posted October 20, 2009 Your totally right CTD a theory of evolution is just ridiculous, I can't believe I didn't see your point earlier.I don't think you see my point yet. If you see it as ridiculous, you see it as extant. We disagree. I see it as vaporware. We just might ridicule it together if you can find it!
toastywombel Posted October 20, 2009 Posted October 20, 2009 You just want to have the last post on this forum don't you.
CTD Posted October 20, 2009 Author Posted October 20, 2009 Enough straw manning with the chart already!Enough lying already! Or don't you know what the term 'straw man' means? I know. Gotta sling mud so you can feel important, or intelligent, or whatever - devoted... A controlled experiment is one way, but not the only way, in which a scientific hypothesis can be tested. You trollish act is not going to work here.I never claimed a controlled experiment was the only way to test an hypothesis. I'm claimin' you ain't got no hypothesises t'be a-testin' nohow. Other than word order, WTF is the difference between "evolution theory" and a "theory of evolution"? You really are a troll, and a bad one at that.You really are a mudslinger, and a bad one at that. Haven't hit the mark even once. Long ago and more than once I explained that the order of the words is meaningful in English. Hoping someone forgot? This is a non-issue. Of course a legitimate theory of evolution exists.I'm not interested in say-so. Figure that out.
mooeypoo Posted October 20, 2009 Posted October 20, 2009 Ad hominem and ridicule attacks have absolutely no room in this forum. Be civil, and follow the rules. ~moo
toastywombel Posted October 20, 2009 Posted October 20, 2009 You ain't got no hypothesis? thats a double negative, so your saying he has a hypothesis.
CTD Posted October 20, 2009 Author Posted October 20, 2009 You just want to have the last post on this forum don't you.You just want to set me up so your partner(s) can whine that some lame, off-topic insult didn't get a response. And no, I'm not ending my sentence with "don't you?" One might ask what the purpose was served by your own post... Merged post follows: Consecutive posts mergedYou ain't got no hypothesis? thats a double negative, so your saying he has a hypothesis.Not what I said. I said "hypothesises" - plural. -And that should be "an hypothesis" there, wise guy.
toastywombel Posted October 20, 2009 Posted October 20, 2009 an only goes in front of words that start with a vowel, last time I checked H is not a vowel. And you did use a double negative regardless if hypothesis was plural or not. Here is a link about the an in front of hypothesis http://forum.wordreference.com/showthread.php?t=1081471
CTD Posted October 20, 2009 Author Posted October 20, 2009 Listen Jackass it was not pre-meditated I have been on this forum for like a week, I hardly know anybody on this forum. The reason the three of us came to the same conclusion is because it is known fact.You've only been here a week, and you confidently behave so? You already understand mindlessly ganging up on the unpopular is the way to go around here? That's meaningful. Would you have me believe you were fooled by that cheap snippin' out-of-context trick? How could anyone reading this thread not understand I've been asking all along to see the "theory of evolution"? How how how how how hww - see what you made me do! "Hww" from my keyboard. Happy now? You better be happy, 'cause provoking too-fast typing is about all you can really threaten, ain't it? You obviously are not going to convince us and we are not going to convince you. Why do you keep posting? Do you feel the need to get in the last word? Does it make you feel better about yourself? Do you really like to waste your time like this? If you believe your theory good for you, go live life. The only things you have provided to this forum is disruption and limited information on male lactation, is this the extent of your knowledge? Why not post on other topics?Nobody's making you read any of this. What? Are you curious that just maybe someone might find the "theory"? Instead you went into a science forum, denounced evolution, and implied that everyone in the forum was godless when everyone pointed out how your arguments were wrong!Untrue. I have repeatedly said I accept the changes in allele frequencies as a factual observation. Why do you insist on pretending otherwise? What does it take to satisfy you - not the rest -just you - that I really do believe this? You came here looking for a fight! Maybe because you have no other way of getting attention! Maybe love conflict I just don't know. But seriously this is beyond ridiculous. There is nothing productive about this.I came here, made a couple of posts, and was challenged to "fight" right off - just like that, for no reason at all. I have never indicated a preference one way or another about fighting. You assume I enjoy it because all the attacks thus far have failed and or backfired. I enjoy funny. There are plenty of other funny thing and plenty of other things I enjoy. Want to understand me? I'll explain a bit. While all the loopy idiots are slingin' mud, what if there's someone with a little actual gray matter lookin' on. What if they get upset and go searchin' and find a legitimate "theory of evolution"? Some people get determined when they get upset, rather than throwing temper tantrums. You think you know so much? You're really that certain that no proper "theory of evolution" has ever existed that you cannot give the community time to find it, but have to stink up the place with childish antics? Gotta hurry up and get me banned? Doesn't bother me. I conclude there are many here who are also, in fact, agreeing by their actions. I think it's obvious enough for anyone who considers the matter. Merged post follows: Consecutive posts merged Does it mean anything to you at all, this issue of whether or not a legit "theory of evolution" exists? If so, why not treat it with respect and investigate? This is a non-issue. Of course a legitimate theory of evolution exists. Textbook double-talk. It matters or it does not matter. There is no in between. If it mattered very much at all, there would be concern. There is none. Zero. We'll need to measure something else just to be sure the concernometer isn't broken. The theory of evolution is a large body of knowledge. The best place to find a complete description is in a textbook on the theory of evolution. Nobody on this forum has the time to write a book just for you. Harkening back to Darwin as an attempt to falsify evolution is just stupid. And just up'n saying "Harkening back to Darwin as an attempt to falsify evolution is just stupid" isn't? Looks like you meant to give the impression I was doing something stupid there, but you have no basis. I did not "harken back" to anyone in my post, or attempt to falsify evolution. I classify this as a variation of straw man - let's call it "ghost man" for now. Darwin was not the be-all and end-all of the theory of evolution. He did not know about genetic theory. He did not know about DNA. Arguing that flaws in Darwin's writings falsifies the theory of evolution is akin to arguing that flaws in the Bohr model of the atom falsifies quantum mechanics. Darwin and Bohr were the starting points of two scientific bodies of knowledge, not the end points.Um ...whatever. Perhaps some phantom will happen along and respond; it doesn't concern me or the topic. So typing up a legit "Theory of evolution" would take tens of thousands of years? Stop with the fallacies already, this time argument from ridicule.Fallacies? Some cyper.... entity... snips my words way way WAY out of context in an attempt to mislead the readership, and calling him on it in an entertaining manner is a fallacy? You people and your delusions... Maybe sometimes I shouldn't, but I do laugh. You give me no choice! post number 64, people, that's where I'm accused of employing "argument from ridicule". Use of fallacies is strictly forbidden by the rules here. The time to ban this utter fool has long since passed. Nothing strict at all about the enforcement. If they banned the utter fools, how many'd be left? If they banned those who've employed fallacies in violation of the rules in this thread alone, how many? Oh, and how much of the "I can't read the OP" fallacy will we continue to see? I know it's long, but really... Most of it's just don't-play-stupid-games stuff. Blame the deceptive: if not for them it wouldn't be there. The real question couldn't be much simpler.
toastywombel Posted October 20, 2009 Posted October 20, 2009 Want the theory of evolution? This is from tellmehowto.com A common question is 'what exactly is evolution, and the theory of evolution?' According to WikiPedia, 'evolution is a change in the traits of living organisms over generations, including the emergence of new species'. Evolution has gone from being one of the most controversial of theories when first stated by Darwin for its perceived undermining of the idea of God, to being generally widely accepted now by virtually everyone. Partly this is due to the fact that over time theories tend to lose their shock value and gain acceptance. Also the more secular world we live in has helped stop the religious objection, but also of course that is perfectly possible for the two to be true together, there is not even close to a logical contradiction between the two statements: 'Evolution is true and God exists'. One of the biggest objections to evolution has come from those that think that there has to be more to life and our current existence than just random choice. That is, that evolution must somehow only be part of the story, as there is no goal orientation, or teleology in it, it is just blind chance (the blind watchmaker). Often the apparent design in current lifeforms seems to argue for some sort of guiding hand or intelligence behind the creation. It is hard to believe for many than random processes and blind chance could result in all the creatures and lifeforms that we see around us. Certainly one interesting point is about so-called intermediate stages. Many can understand how species survive once 'fully adapted' but what happens in those intervening periods where the adaptations to environment are forming over tens of thousands of years - how does the species survive these intermediate periods where for instance a horn is just starting to form or a tail just growing but still pretty useless? Additionally, many have wondered whether there has been enough time for just 'blind chance' to produce the staggering away of life we know exists, given the rough age at which life is acknowledged to have begun. Another objection often made is with regard to the actual content of the theory which is, let's face it, staggeringly simple. Essentially, that change occurs and new species occur from random mutations in genes that lead to some individuals to be better adapted to environment 'e' at time 't' than others, and therefore if conditions remain close enough to 'e' at time 't + n' such that the advantage holds, that individual and its decendents are more likely to survive and breed than other members of that species, ultimately leading to the formation of a new species. Or maybe your more likely to believe David A. Rizwan http://www.geocities.com/plecoboy88/Evolution.html Evolution. Most people have heard of it, but not too many believe that it is possible. However, most people that see it as false do not understand it. I will try to clarify the blurry points in the Modern Evolutionary Theory. Simply put, Evolution is the process through which animals change over time. However, this seems to sum the story up a little too much. Most people that do not believe in Evolution do not fully understand it. Those people believe that the theory says that humans came from monkeys. This is not true. Those people believe that if an animal evolves, there is no prerequisite to the present animal alive. This is not true either. The Theory of Evolution simply explains how life changes over time. This isn’t a few weeks, years, or even centuries. In most cases, this takes millions of years to be complete. The whole evolution process begins with a mutation. A mutation is any animal that is different from the norm. For instance, an albino garter snake is a mutation. A lucistic alligator is a mutation. Anything that is not normal in a living creature’s DNA is a mutation. It is obvious that some mutations would be more beneficial than others. This is where “Survival of the Fittest” comes into play. For instance, a longer bill on a nectar-feeding bird is beneficial, as it allows the bird to gather nectar much easier. Other mutations, such as an albino snake in a dark green jungle, are actually malicious. It is obvious that this snake will not be able to camouflage from predators while it is still young, making it an easy meal. The snake will never survive to the age to reproduce. The animals that are best matched to their environment will survive more, thus reproduce more. There are sometimes periods in which the environment changes, such as the Ice Age. During the period of time, most of the world became icy and snow covered. The animals with a gene to have longer hair would usually die of heat exhaustion in the previous era. But now their hair is able to keep heat in their body, allowing them to survive better than the non-haired ones. The without hair began to die out, leaving only the ones with hair. The species had just evolved. As the environment changes, those that are fit to the new environment survive and reproduce, those that aren’t, die off. Sometimes animals are separated from other animals of their species, such as the Galapagos Islands. These animals have a closed gene pool away from the other animals, and they also live in a different terrain type. This means that two samples of a species can evolve differently. One sample of a bird species may develop a longer bill to allow for easier food gathering, while the other sample develops a shorter bill for more control over the bill, and the final sample of the bird species may remain unchanged. Eventually through these changes and others, the two birds will eventually be so different that they can no longer reproduce. Another new species now exists. Many believe that there is no evidence to support evolution. On the contrary, there is much more evidence than the other theories for how life came to be. When you compare two cats taxonomically, they are the same species. They can reproduce and produce fertile young. This means that all of the cat species are the same, Felis Domesticus. How did all of these come to be? Selective breeding is the key. Selective breeding is basically forced evolution upon a species. When people saw the first Siamese cat, they decided to make more. By breeding them with another cat, there is a chance to produce more of that mutation. More evidence to prove the existence evolution is homologous structures. These are structures that are made of the same thing, but fill different tasks. If you examine the skeletal structure of a whale flipper, it has the same bones as a human hand. There are many other situations such as this. In conclusion, Evolution is a rather simple topic if you put time into fully understanding it. To evolve, all a species needs is a beneficial mutation and the death of the original version of the species. When an isolated species evolves away from the original population, it will form a new species. Since the original version is still alive, the species hasn’t evolved, but a new species has formed. If your not a reader than you could watch this. Or you can simply go to wikipedia and search theory of evolution. And so you don't try to pull that "its does not fit the description of theory bull" here is the definitions of theory Theory The"o*ry, n.; pl. Theories. [F. th['e]orie, L. theoria, Gr. ? a beholding, spectacle, contemplation, speculation, fr. ? a spectator, ? to see, view. See Theater.] 1. A doctrine, or scheme of things, which terminates in speculation or contemplation, without a view to practice; hypothesis; speculation. [1913 Webster] Note: "This word is employed by English writers in a very loose and improper sense. It is with them usually convertible into hypothesis, and hypothesis is commonly used as another term for conjecture. The terms theory and theoretical are properly used in opposition to the terms practice and practical. In this sense, they were exclusively employed by the ancients; and in this sense, they are almost exclusively employed by the Continental philosophers." --Sir W. Hamilton. [1913 Webster] 2. An exposition of the general or abstract principles of any science; as, the theory of music. [1913 Webster] 3. The science, as distinguished from the art; as, the theory and practice of medicine. [1913 Webster] 4. The philosophical explanation of phenomena, either physical or moral; as, Lavoisier's theory of combustion; Adam Smith's theory of moral sentiments. [1913 Webster] Atomic theory, theory}, etc. See under Atomic, Binary, etc. [1913 Webster] Syn: Hypothesis, speculation. Usage: Theory, Hypothesis. A theory is a scheme of the relations subsisting between the parts of a systematic whole; an hypothesis is a tentative conjecture respecting a cause of phenomena. [1913 Webster] Here are the definition of "theory" from google a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of ... hypothesis: a tentative insight into the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena; "a scientific hypothesis that survives experimental testing becomes a scientific theory"; "he proposed a fresh theory of alkalis that later was ... a belief that can guide behavior; "the architect has a theory that more is less"; "they killed him on the theory that dead men tell no tales" wordnetweb.princeton.edu/perl/webwn The game of chess is commonly divided into three phases: the opening, middlegame, and endgame. As to each of these phases, especially the opening and endgame, there is a large body of theory as how the game should be played. ... en.wikipedia.org/wiki/Theory_(chess) theory (marketed in lower-case letters) is a New York-based men's and women's contemporary sportswear fashion label known for its clean-line and luxuriously simple clothes and accessories. theory merchandise is sold through signature theory stores and upscale retailers around the world. ... en.wikipedia.org/wiki/Theory_(brand) In mathematical logic, a theory is a set of sentences in a formal language. For example, a first-order theory is a set of first-order sentences. Many authors require that the theory be closed under logical consequence. en.wikipedia.org/wiki/Theory_(mathematical_logic) A theory, in the general sense of the word, is an analytic structure designed to explain a set of observations. ... en.wikipedia.org/wiki/Theory An unproven conjecture; An expectation of what should happen, barring unforeseen circumstances; (sciences) A coherent statement or set of statements that attempts to explain observed phenomena; (sciences) A logical structure that enables one to deduce the possible results of every experiment ... en.wiktionary.org/wiki/theory A hypothesis that has withstood extensive testing by a variety of methods, and in which a higher degree of certainty may be placed. A theory is NEVER a fact, but instead is an attempt to explain one or more facts. blue.utb.edu/biology/oliva/terms_and_definitions_for_quiz_1.htm a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena. In other words, it is the general or abstract principles of a body of fact, a science. http://www.bioethismscience.org/bioetscienc/biblio_index/glossary1.htm The weight a person or an animal maintains and returns to after dieting or overfeeding. Setpoint varies with age and activity levels, and may be raised if the organism is subject to chronic deprivation. http://www.strugglingwithfood.com/EDDefinitions.htm The body of rules, ideas, principles, and techniques that applies to a particular subject. http://www.edgateway.net/pub/docs/pel/glossary.htm is an explanation of some phenomenon. More specifically, it is an explanation of the relationship between two or more concepts or variables. ... roanoke.edu/Documents/Glossary%20%20%2007.doc several related propositions that explain some domain of inquiry. Also called a school or paradigm. oregonstate.edu/instruct/anth370/gloss.html An explanation of a natural occurrence that is testable and capable of predicting future occurrences. spaceplace.nasa.gov/en/kids/spitzer/signs/sign_glossary.shtml Evolution is a theory, which means that it is not a Law, If you have a better theory that more accurately predicts the nature of biological life on planet earth please tell me. Merged post follows: Consecutive posts mergedHere is another take on the theory of evolution from actionbioscience.org Scientific understanding requires both facts and theories that can explain those facts in a coherent manner. Evolution, in this context, is both a fact and a theory. It is an incontrovertible fact that organisms have changed, or evolved, during the history of life on Earth. And biologists have identified and investigated mechanisms that can explain the major patterns of change. Patterns in Nature The field of evolutionary biology seeks to provide explanations for four conspicuous patterns that are manifest in nature. The first three concern living species, whereas the fourth relates to fossils. Genetic variation. There is tremendous genetic diversity within almost all species, including humans. No two individuals have the same DNA sequence, with the exception of identical twins or clones. This genetic variation contributes to phenotypic variation — that is, diversity in the outward appearance and behavior of individuals of the same species. Adaptation. Living organisms have morphological, biochemical, and behavioral features that make them well adapted for life in the environments in which they are usually found. For example, consider the hollow bones and feathers of birds that enable them to fly, or the cryptic coloration that allows many organisms to hide from their predators. These features may give the superficial appearance that organisms were designed by a creator (or engineer) to live in a particular environment. Evolutionary biology has demonstrated that adaptations arise through selection acting on genetic variation. Divergence. All living species differ from one another. In some cases, these differences are subtle, while in other cases the differences are dramatic. Carl Linnaeus (1707-1778) proposed a classification that is still used today with slight changes. In the modern scheme, similar species are grouped into genera, similar genera into families, and so on. This hierarchical pattern of relationship produces a tree-like pattern, which implies a process of splitting and divergence from a common ancestor. Fossil species . Fossils are the mineralized remnants or impressions of once-living organisms. Many fossils, such as trilobites and dinosaurs, belong to groups that no longer exist on the face of the Earth. Conversely, many modern species appear similar to other fossils, yet fossils of the modern species are absent from rocks of corresponding ages. The age of the Earth is estimated to be about 4.5 billion years, with the earliest bacterial fossils about 3.5 billion years old. Fossils from around 550 million years ago (the Cambrian period) show a diverse assemblage of multicellular animals. Evolutionary biology provides a scientific framework for understanding the changes that have occurred since the first life forms arose on Earth several billion years ago. Biochemists, geologists, and physicists seek natural explanations for the origin of life on Earth. While progress has been made in this area, the origin of life remains an interesting, but unanswered, question. Mechanisms of Evolution Biological evolution results from changes over time in the genetic constitution of species. Genetic changes often, but not always, produce noticeable changes in the appearance or behavior of organisms. Evolution requires both the production of variation and the spread of some variants that replace others. Genetic variation arises through two processes, mutation and recombination. Mutation occurs when DNA is imperfectly copied during replication, leading to a difference between a parent’s gene and that of its offspring. Some mutations affect only one bit in the DNA; others produce rearrangements of large blocks of DNA. Recombination occurs when genes from two parents are shuffled to produce an offspring, as happens regularly in sexual reproduction. Usually the two parents belong to the same species, but sometimes (especially in bacteria) genes move between more distantly related organisms. The fate of any particular genetic variant depends on two processes, drift and selection. Drift refers to random fluctuations in gene frequency, and its effects are usually seen at the level of DNA. Ten flips of a coin do not always produce exactly five heads and five tails; drift refers to the same statistical issue applied to the transmission of genetic variants across generations. The principle of natural selection was discovered by Charles Darwin (1809-1882), and it is the process by which organisms become adapted to their environments. Selection occurs when some individual organisms have genes that encode physical or behavioral features that allow them to better harvest resources, avoid predators, and such relative to other individuals that do not carry the same genes. The individuals that have these useful features will tend to leave more offspring than other individuals, so the responsible genes will become more common over time, leading the population as a whole to become better adapted. The process that many people find most confusing about evolution is speciation, which is not a separate mechanism at all, but rather a consequence of the preceding mechanisms played out in time and space. Speciation occurs when a population changes sufficiently over time that it becomes convenient to refer to the early and late forms by different names. Speciation also occurs when one population splits into two distinct forms that can no longer interbreed. Reproductive isolation does not generally happen in one generation; it may require many thousands of generations when, for example, one part of a population becomes geographically separated from the rest and adapts to a new environment. Given time, it is inevitable that two populations that live apart will diverge by mutation, drift, and selection until eventually their genes are no longer compatible for successful reproduction. Evidence for Evolution, and its Significance in our Lives It is impossible to review all the evidence for evolution in a short article such as this. However, the following offers a sample of the kinds of evidence that have been discovered and confirmed repeatedly by scientists. These examples also illustrate the importance of this evidence for science and society more generally. Evidence from fossils. Based on myriad similarities and differences between living species, evolutionary biology makes predictions about the features of ancestral forms. For example, numerous features indicate that birds are derived from reptilian ancestors. By contrast, these data reject the possibility that birds were derived from other groups, such as flying insects. Scientists have discovered fossil birds with feathers and legs like modern birds, but which also have teeth, clawed digits on their forelimbs, and a tailbone like their reptilian ancestors. Fossils are especially important evidence for evolution because, with little effort, each of us can use our eyes and minds to observe and interpret the dinosaur and other ancient fossils in public museums. Evidence from genetics. The genomes of all organisms contain overwhelming evidence for evolution. All living species share the same basic mechanism of heredity using DNA (or RNA in some viruses) to encode genes that are passed from parent to offspring, and which are transcribed and translated into proteins during each organism’s life. Using DNA sequences, biologists quantify the genetic similarities and differences among species, in order to determine which species are more closely related to one another and which are more distantly related. In doing so, biologists use essentially the same evidence and logic used to determine paternity in lawsuits. The pattern of genetic relatedness between all species indicates a branching tree that implies divergence from a common ancestor. Within this tree of life, there are also occasional reticulations where two branches fuse, rather than separate. (For example, mitochondria are organelles found in the cells of plants and animals. Mitochondria have their own genes, which are more similar to genes in bacteria than to genes on the chromosomes in the cell nucleus. Thus, one of our distant ancestors arose from a symbiosis of two different cell types.) The genetic similarity between species, which exists by virtue of evolution from the same ancestral form, is an essential fact that underlies biomedical research. This similarity allows us to begin to understand the effects of our own genes by conducting research on genes from other species. For example, genes that control the process of DNA repair in bacteria, flies, and mice have been discovered to influence certain cancers in humans. These findings also suggest strategies for intervention that can be explored in other species before testing on humans. Evolution in action. Evolutionary change continues to this day, and it will proceed so long as life itself exists. In recent years, many bacterial pathogens have evolved resistance to antibiotics used to cure infections, thereby requiring the development of new and more costly treatments. In some frightening cases, bacteria have evolved resistance to every available antibiotic, so there is no longer any effective treatment. In the case of HIV, which causes AIDS, significant viral evolution occurs within the course of infection of a single patient, and this rapid evolution enables the virus to evade the immune system. Many agricultural pests have evolved resistance to chemicals that farmers have used for only a few decades. As we work to control diseases and pests, the responsible organisms have been evolving to escape our controls. Moreover, scientists can perform experiments to study evolution in real time, just as experiments are used to observe dynamic processes in physics, chemistry, and other branches of biology. To study evolution in action, scientists use organisms like bacteria and fruitflies that reproduce quickly, so they can see changes that require many generations. Conclusions Evolutionary biology is a strong and vigorous field of science. A theoretical framework that encompasses several basic mechanisms is consistent with the patterns seen in nature; and there is abundant evidence demonstrating the action of these mechanisms as well as their contributions to nature. Hence, evolution is both a theory and a set of established facts that the theory explains. Like every other science, there is scientific debate about some aspects of evolution, but none of these debates appear likely to shake the foundations of this field. There exists no other scientific explanation that can account for all the patterns in nature, only non-scientific explanations that require a miraculous force, like a creator. Such super-natural explanations lie outside of science, which can neither prove nor disprove miracles. Science provides us with a compelling account and explanation of the changing life on Earth. It should also remind us of our good fortune to have come into being and our great responsibility to ensure the continuity of life. This article was written by Richard E. Lenski PhD he has written more than 100 articles on ecology, genetics, and evolution. He is a fellow of the American Academy of Arts and Sciences, the American Academy of Microbiology, and the MacArthur Foundation. At Michigan State University, he is the Hannah Professor of Microbial Ecology. But I am guessing you are smarter and more accomplished than even Mr. Lenski Merged post follows: Consecutive posts mergedHere is some more on evidence for evolution by Lukas K. Beuler who has a PhD in biochemistry. Evidence of Evolution Let's have a look at the type of evidence that supports Darwin's theory of evolution and the modern synthesis, which combines natural selection with the concept of species and population genetics. The latter is the modern application of the patterns of inheritance as first described by Gregor Mendel (1822-1884), a contemporary of Charles Darwin (1809 -1882). Evidence of evolution comes from categorizing similarities among organisms living on distant locations, e.g., continents. Biogeography was central to Darwin's logic when he summarized his findings from five years of collecting evidence around the world as a passenger on the HMS Beagle. He realized that animal and plant species, though diverse, were more similar to each other on the same continent. Australian species were more similar to each other than they were to South American species. But such geographic diversity also played out on local island groups such as those of the Archipelago Galapagos in the South Pacific. The famous Darwin finches were his prime exhibit in formulating the theory of evolution. The idea is that species change over time in different direction if they live isolated from each other over long periods of time. Time periods in evolution are truly long and are measured in geological time, e.g. MYA or million years ago. Fossil records together with the theory on plate tectonics and continental drift support the idea of speciation as a result of long lasting geographic isolation. Speciation is the process of evolving two separate species from a founder species after an event caused separation of the founder population into two isolated population where individuals from one population cease to reproduce with individuals from the other population. Evidence of diversity and similarity comes from comparative anatomy and comparative embryology. Often, we find similar anatomical features in animals and plants that are used for different functions. Examples are the human arm used for grabbing, whose skeletal anatomy looks similar to that of the forelimb of a cat used for walking, but also looks similar to the skeletal anatomy of the flipper of a whale used for swimming and the wing of a bat, used for flying. The bone structures in all four limbs are strikingly similar in their anatomical plan, suggesting that the four different animals are all descendants of a common ancestral animal form. Each modern animal has evolved independently of all others and has adapted a limb structure that fits the different usage. They have, however, not changed completely and are considered homologous structures. The idea of homology points towards a structural similarity of body parts that are used for different functions. In some instances, organisms that are clearly not related have evolved similar structures for the same function. This structural similarity for the sake of the same function is the result of convergent evolution. Such structures are called analogous, indicating that their similarity, unlike the structural similarities of homologous structures, is not the result of descent with modifications. Some of the most convincing evidence comes from modern molecular biology demonstrating that similarities at the molecular level - protein structures and gene sequences - can be used to determine evolutionary relationship. Molecular evidence has spectacularly supported the theory of evolution The power of molecular analysis is straight forward; the modifications mentioned by Darwin are really the result of random mutations in our genes. Genes contain the instructions to make proteins. Proteins are the true causes of physical traits. It is these traits that are edited by natural selection, i.e., how well an individual organism can live in changing environments and has the opportunity to have as much offspring as possible. It is the number of fertile offspring that is the true measure of Darwinian fitness. It is not, as many people believe, the survival of the fittest, often meant to mean the strongest individual. The meaning of strength is relative and is often shaped by chance events. As a result, descent with modification is neither directed nor is it able to create the perfect species. Perfection often means reduced ability to adapt, to make use of modifications when the environment changes drastically. Drastic changes are thought to be global climate changes such as warming and cooling. Most organisms are very sensitive to the average temperature, or their food, i.e., the organisms they feed on may be very sensitive to changes in temperature and disappear, leaving even the strongest of animals in limbo, without food, and thus may risk extinction if it cannot change its way of life. Mechanisms of Evolution The first correct account of the mechanism of evolution has been proposed by Charles Darwin. In his theory of evolution, he suggested natural selection to explain the 'descent with modification'. Natural selection of already existing traits best explains how species could change over time by adapting to environmental changes. Darwin suggested that modifications are present in individuals, as can readily be seen in humans and any other animal or plant species. These differences among individuals of the same group (species or population) can be inherited (Gregor Mendel showed how) and individuals of the next generations always have different combinations of traits. Natural selection is thought to edit which traits are best suited to have the most offspring. It will be these traits that will also be found more often in the next generation. Thus the environment (natural selection) affects the obvious variability found in all animal and plant species. Today we understand natural selection in more details and at the level of genes and mutations. We also understand that many times mutations and corresponding traits can be inherited more frequently or less frequently just by chance, not just because of a physiological advantage. This chance element is a critical part of the modern theory of evolution and explains why this process does not produce designed features as if nature could foresee what is best. Rather, mutations make random adjustments to an individuals physiological capacity and the more offspring an individual has, the more copies of its particular genes it will pass on to the next generation. The measurement of the number of offspring gives an unbiased account of evolutionary success, or Darwinian fitness. In this theory, you propose that you make changes and then see which ones serve you best. With this in mind, it is easy to understand that evolution is an ongoing process, and that evolution will not be able to produce the perfect organism. The latter is impossible because the environment keeps changing, and natural selection can only favor or disfavor traits that are already there. To understand the inability of perfection, one only has to think about the myriad of diseases that afflict humans and any other species. Furthermore, many changes do not result in beneficial or detrimental traits. They are said to be neutral and are unaffected by the environment. However, they are still subject to additional random changes. If two populations of individuals reproduce in distinct locations, or because they prefer different mating habits, they can accumulate changes in their genepool independent of each other. After many generations, these changes may restrict successful mating, even if individuals from two isolated populations are given a chance to mate. A natural or biological barrier has evolved that is now reinforcing further independent changes that will likely result in these two populations to be quite different after millions of generations. These reproductive barriers are important steps in forming new species from an ancestral species. If this process of speciation occurs repeatedly, many different derived species can exist. Their common ancestral origin, however, can still be estimated by comparing similarities in anatomical features, behavioral traits, or molecular sequences (genes, proteins).
CTD Posted October 20, 2009 Author Posted October 20, 2009 1, 2, 3, 4, 5, 5, 6, 7 Can you find the OP or should I copy & paste?
toastywombel Posted October 20, 2009 Posted October 20, 2009 (edited) You asked for the theory of evolution, I just gave it to you, in various forms. If you cannot accept that the theory of evolution exists (i'm not even asking you to believe it) you must be mentally retarded. Merged post follows: Consecutive posts mergedAnd you did not even read any of the information I provided for you! You responded like 2 minutes after i posted all that info. Merged post follows: Consecutive posts mergedFurthermore you were insinuating that I was lying earlier when I said I joined like a week ago right? It says on my profile and at the bottom of every post I have made that I joined October 10th, two days before you joined. Edited October 20, 2009 by toastywombel Consecutive posts merged.
mooeypoo Posted October 31, 2009 Posted October 31, 2009 Guys, please stop taking the law into your own hands. We are a community, not a prisonhouse; if you think a post is against the rules, report it, and let us deal with it. If you think a discussion is not going the way you want it to go, stop participating in it. Ganging up on a member doesn't help matters at all, whether you think it's justified or not. Please let us handle things. ~moo
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