Evolution

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The Silent Ape : On The Origins Of Language This article is a highly speculative account of how our distant ancestors evolved the capacity for speech, together with the evolved capacities that would later be exapted to the behavioural functions of reading and writing. I shall not pretend to be an infallible guide. Whenever you have a chance, take counsel with other travelers who have passed along the same route before. Compare their observations with mine and if this leads you to different conclusions, I shall certainly not be angry with you. Hendrik Willem Van Loon  (1882-1944), …
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New Hominid Discovered :  Anoiapithecus brevirostris Edit: were you looking for - New Hominid discovered in Denisova Cave? New Hominid Discovered :  Anoiapithecus brevirostris A study published in PNAS describes a male partial face with mandible of a previously undescribed fossil hominid, Anoiapithecus brevirostris.   The scientific name is derived from l'Anoia, the region where the fossil was found, and from the description 'reduced facial prognathism', or  'short face'. this discovery enables to identify two probable candidates to be the ancestral form to our…
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Kin selection is one of those special considerations derived from “selfish gene theory” that postulates that it is the degree of relatedness between organisms that will determine the likelihood that altruistic actions will occur. This also clearly implies the existence of a social group, of some type, so it isn’t expected that it would play a role between members of different species, or among asocial animals (although it could). In general the idea of “kin selection” is that individuals are more apt to behave altruistically to “blood relatives” than to others in the interest of propagating…
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The idea of the “selfish gene” was intended to shift focus from the organism to the gene to provide a different perspective on natural selection. It was been described as a metaphor, or simply a semantic issue. However, without precision in our use of such words, we risk creating assumptions and assigning values where none exist. This is the same problem that occurs in describing animal behavior when one anthropomorphizes. “The key question, as we shall see, is how natural selection can produce selfish genes that prescribe unselfishness.”Bert Hölldobler and Edward.O.Wilson, The Ants As can…
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Contrary to many notions about predators, it would seem that there are many whose success is directly linked to their social organization and more specifically to the role of the social leaders that may direct the group. Predation is, by its nature, an energy intensive, high risk endeavor. Unexpected events may occur resulting in injuries, which may directly affect the ability of the predator to survive. Except in the cases of resource constraint, or exceptionally large animals, it makes sense to spread the risk among more individuals. This becomes especially important when sickness or…
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No. 1 “Evolution is the external and visible manifestation of the differential survival of alternative replicators.” This is my all-time favourite, the Dawkins Fallacy, the definition of evolution Richard Dawkins gave in The Extended Phenotype p.82. The fallacy it contains is so obvious I’m amazed that his colleagues have not drawn his attention to it. The survival of replicators is a result of evolution, an outcome, and therefore cannot be the definition of evolution. If we said that fire is the visible manifestation of the production of ash, the statement would be true but meaningless. It…
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 “May you live in interesting times!” So goes the ancient Chinese curse, and times certainly must have been interesting for Alexander Ivanovich Oparin, who was 23 years old when he graduated from Moscow State University in 1917. Lenin and the Bolsheviks had just seized power, the Czar and his family were imprisoned, then assassinated a year later, and the war between Red and White Russia began. But the young scientist managed to avoid getting caught up the chaos, perhaps because he was thinking about something far more interesting and fundamental than politics: How did life begin? Oparin…
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The issue of altruism in animals is well recognized, but the explanation has always been strained. In particular, the idea that altruism would be beneficial at the group level gave rise to the idea of "group selection". The problems intrinsic in this idea were that such groups could be potentially invaded by "selfish" individuals and thereby tip the scales in the opposite direction. A serious flaw with this argument was pointed out by Patrick Lockerby in stating "It is against the evolution of a group to allow the cheat to join. Cheaters are not joiners. Cheats 'break up the party." From…
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Teasing out the effects of natural selection on our genomes from the effects of other evolutionary processes is hard. A group at the University of Washington, using comparisons with the genomes of 5 other primate species, takes a crack at it: Comparisons of the human and chimpanzee genomes have revealed that the frequency of sequence differences between these species varies dramatically across the genome. Previously proposed explanations for this variation include a large ancestral population, variable mutation rates, or a complex speciation scenario in which humans and chimpanzees initially…
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In the last few columns, I described how laboratory simulations of a volcanic prebiotic environment showed that interesting organic reactions can be driven by the heat and pressure associated with vulcanism. I also described my own studies of volcanic sites on the present Earth, which we call prebiotic analogue environments, and pointed out some of the problems that arise when we try to duplicate laboratory experiments in the real world geothermal conditions.  In the comments following the column, Gerhard Adam suggested that ice might be a plausible alternative to a hot site for the…