Rating: 
Summary: A zippier title: Genetic Meltdown in the Human Species
Review: We are "complex life".
Is our complexity limited by the rate of DNA copying error?
Simple life reproduces and evolves much faster than complex life.
Time measured by physics and fossils versus time measured by DNA changes.
Life existed 3500 mya (million years before present)
but fossils only go back a mere 550 mya.
It took a long time for complex life to evolve.
Live complexity hits its ceiling when the DNA message
is so long that a mistake happens every time it is copied.
For each organism, the important issue is that one or more of its
many offspring must be correctly copied.
Human beings seem to make about 200 copying mistakes in each child!
Most of this error is irrelevant (in junk DNA?).
The harmful mutation rate per generation is about 2-20.
Shocking! We are in the paradoxical zone.
RNA is more fragile. Because of their copy error rates,
RNA viruses could not evolve to be much bigger than they already are.
Bacteria use DNA as we do so they can be much bigger.
Base C is the main culprit; it tends to mutate to base U.
Mukai's experiment. Kondrashev's theory.
Is the paradox explained by sex?
Sexual selection tends to group good genes with good and bad with bad.
[Only good with good survive? (under prehistoric conditions)].
This was the place to mention the genetic advantages of female infidelity
but he didn't.Complex life is at odds with internal gene competition.
Here, I the reviewer am not convinced of one of the author's major claims,
"The deep nature of maleness is to eject organelles from reproductive cells;
the deep nature of femaleness is to keep them."
I recall the "neutral theory" of evolution,
that many genetic changes make no difference to fitness.
It's like the "null space" in algebra.
A wide variety of models may have equal fitness.
He hasn't convinced me that organelle competition is destructive. Page 184 explains the double division in meiosis as
a mechanism for limiting gene competition.
I don't understand this point yet but
I intend to return to the book many times in the future until I do. The books ends with a chapter on The Human Condition and one on A Complex Future.
Although he enjoys a tongue-in-cheek discussion of sex of angels,
the book does not focus as sharply as it should on the fearsome question
that it should: How fast will our species will decline if we
are all good citizens and have our alloted 2.3 children?
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