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Re: Looking for a pdf of Persson 1960
This got my attention instead
http://www.theonion.com/articles/anthropologists-trace-human-origins-back-to-one-la,19191/
----- Original Message -----
From: "Pedro Luna" <peluna@terra.com.br>
To: "DML" <dinosaur@usc.edu>
Sent: Friday, February 18, 2011 12:25 PM
Subject: Fwd: Looking for a pdf of Persson 1960
Hi, folks
Did you notice it?
Sherman J. Silber. 2011. Human male infertility, the Y chromosome, and
dinosaur extinction. Middle East Fertility Society Journal, In Press,
Corrected Proof, Available online 17 February 2011
Study of the molecular genetics of human male infertility and the Y
chromosome has helped to elucidate the evolution of our X and Y
chromosomes. Particularly, the study of the Y chromosome in male
infertility has also helped to clarify, in a surprising and unexpected
way, a likely mechanism for dinosaur extinction, the biggest question all
of us have entertained from our earliest childhood days.
There have been many claims in the popular press of “discoveries” on how
the dinosaurs went extinct. These claims all relate to climate change
events that occurred 65 million years ago that no one disputes occurred.
But none have explored the biology of how so many animals escaped
extinction while the dinosaurs and at least half of all other species did
not. For example, why did large dinosaurs, as well as small dinosaurs the
same size as chickens go extinct, but birds survived? Possibly the
evolution of sex chromosomes holds the answer to this question.
Our studies of the Y chromosome and male infertility suggest that the
default mechanism for determining the sex of offspring is the temperature
of egg incubation, and that genetic sex determination (based on sex
chromosomes like X and Y) has evolved many times over and over again in
different ways, in different genera, as a more foolproof method than
temperature variation of assuring a balanced sex ratio in offspring. The
absence of such a genetic sex determining mechanism in dinosaurs may have
led to a skewed sex ratio when global temperature dramatically changed
65,000,000 years ago, resulting in a preponderance of males, and
consequentially a rapid decline in population.
best
Peter Moon
Sao Paulo, Brazil