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inbreeding as increasing the mutation rate of a species ; NOVA
"Decoding Neanderthal" #200 Rockthrowing theory book
Posted:
Jan 26, 2013 12:23 AM
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--- quoting from Concepts of Biology: a cultural perspective, Buffaloe
& Throneberry, 1973, page 240
---
In sexual reproduction, different gene combinations may be brought
together in the formation of a new genotype. Any differences in
allelic genes depend ultimately upon mutation, of course; but, for the
new organism, its gene pattern is a result of the new combinations
brought about through sexual reproduction. We call this phenomenon
recombination, and it may be defined as the production of new
genotypes from genes that already exist. By its nature, therefore,
recombination is a secondary source of genetic variability.
--- end quote ---
The authors of this textbook define the modern theory of Evolution, a
synthesis of 4 mechanism:
1) Mutation
2) Genetic Recombination
3) Natural Selection
4) Reproductive Isolation
What I am focusing on in this review of Neanderthal and Clovis man and
human evolution, is the factor of inbreeding when a population is
isolated. I do not think a proper study of inbreeding has ever been
done and questions of whether the mutation rate increases with a
inbreeding population.
Now one can argue almost the opposite in that African Homo sapiens
mutation of the HACNS1 gene for superior throwing of rocks and stones
is a mutation that the Neanderthal did not acquire. But I surely do
not know how many mutations differing in Neanderthal genome from that
of Homo sapiens other than the definition of different species of a
minimum of 3 mutations.
I am not arguing against David's issue of increased recessiveness of
genotype or phenotype. I am arguing that increasing recessiveness
contributes to an increased mutation rate.
Now if we put animals near a source of radioactivity and increased the
radioactivity, we can easily picture an increase in mutation. But here
I am saying that if we put a species where we pluck out 1 male and 1
female and isolate them and have them start a population by
themselves, meaning a lot of inbreeding, that the mutation rate
increases. The recessive genes help to increase the mutation rate. One
way of seeing this is that some recessive genetypes allow more viral
diseases and viruses are known to carry mutagens.
Another means of increasing the mutation rate in an inbreeding
population, is that the recombination poses "points of weakness" in
the formation stages of meiosis or mitosis due to the abundance of
recessive genes.
--
Google's archives are top-heavy in hate-spew from search-engine-
bombing. Only Drexel's Math Forum has done a excellent, simple and
fair archiving of AP posts for the past 15 years as seen here:
http://mathforum.org/kb/profile.jspa?userID=499986
Archimedes Plutonium
http://www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies
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