Evolution of Intelligence (Origins)

by Balance_Maintained @, U.S.A., Thursday, March 28, 2013, 15:01 (4019 days ago) @ David Turell

Primate brains reorganized over 40 million years, so not just size counts:-Pure speculation...and it will never be anything more than that. It also means it is impossible to falsify the theory. I thought that was kind of a requirement in good science.-http://www.nature.com/news/dna-has-a-521-year-half-life-1.11555-Nature-&quot;The molecular clock hypothesis states that DNA and protein sequences evolve at a rate that is relatively constant over time and among different organisms. A direct consequence of this constancy is that the genetic difference between any two species is proportional to the time since these species last shared a common ancestor. &quot;-&#13;&#10;THE concept of a molecular clock grew out of the observation that proteins appear to evolve at a nearly constant rate (ZUCKERKANDaLn d PAULING&#13;&#10;1965; WILSON,C ARLSONa nd WHITE 1977). However, as early as 197 1, OHTA&#13;&#10;and KIMURA pointed out that the rates of evolution are not constant, but&#13;&#10;rather, they vary significantly from lineage to lineage. This observation has&#13;&#10;subsequently been verified by a number of people (e.g., LANGLEY and FITCH&#13;&#10;1974; KIMURA 1983). A common statistic that quantifies the variability in rates&#13;&#10;of evolution is R, defined as the ratio of the variance in the number of substitutionsin a lineage to the mean number. For proteins, R is usually in the&#13;&#10;range 1.0 < R < 3.4 (LANGLEYa nd FITCH 1974; KIMURA 1983; GILLESPIE&#13;&#10;1984b, among others).-There are two very different interpretations of these estimates of R. KIMURA&#13;&#10;(1983) claims that, as R is close to one, it suggests that evolutionary rates are nearly constant and that the events of molecular evolution may be approximated by a Poisson process (for which R = 1). This interpretation is also used to support the neutral allele theory, since the substitution process for this theory is close to a Poisson process (GILLESPIaEn d LANGLEY19 79; WATTERSON&#13;&#10;1982a,b).-A second interpretation is that inferences about the variance in&#13;&#10;evolutionary rates from the observed values of R are severely biased toward&#13;&#10;one (GILLESPIE1 98413, I986b). When this bias is accounted for, the fact that we can measure R values as large as two or three suggests that the real variance in evolutionary rates might be very large-so large, in fact, that molecular evolution may well be episodic, with bursts of substitutions separated by long periods with no substitutions.&#13;&#10;&#13;&#10;Genetics 113: 1077-1091 August, 1986.&#13;&#10;1078 J. H. GILLESPIE-&#13;&#10;&quot;One of the classic examples of a high mutation rate can be found in many bacteria and viruses. These organisms find it beneficial to mutate rapidly, because they reproduce in huge numbers, so losing numerous individuals doesn&apos;t hurt the species as a whole. The high rate of mutation also allows them to adapt to situations which can include the need to incubate for an extended period of time, or the introduction of new drugs which kill off many individuals within the species.&quot;-------------------------------------------------------------------------So.. essentially, the mutation rate is constant, except for when we observe it not being constant, and then it is because evolution allows for rapid adaptation for survivability, which of course did not happen for any other species but the ones we observed, because if it did that would bugger up our timelines. Oh, and since DNA can not survive more than a few million years, at best, you will never be able to falsify the 40 million year old divergence rate for which we have no evidence but assumption and speculation. Oh.. and one more thing, we have never recorded any 40 million year old DNA, so we don&apos;t REALLY have a baseline for these assumptions. We are not comparing modern humans to ancient humans, cause their DNA is pretty much the same and doesn&apos;t fit the theory. Instead, we are comparing modern human dna to monkey dna, cause we all evolved from monkeys you know, and then based on how they are different, we are estimating the time of divergence based on an assumption that is based on an enigma wrapped up in a mystery. What, you expected observations?-&#13;&#10;Sure.. I&apos;ll buy that.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.


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