Dino Notes

[steve.cole@genie.com]

Sorry to be late with these....
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All about Eve not just one, and much older
 By Deborah Zabarenko
 WASHINGTON, Dec 21 (Reuter) - Bad news for Eve: a new report disputes the
theory that one genetic mother of us all lived 200,000 years ago in Africa,
arguing that there had to be some 100,000 "Eves" existing much earlier in time.
 The report in Friday's edition of the journal Science that our earliest
genetic forbears existed perhaps 60 million years ago, long before human beings
walked the earth, contradicts the "mitochondrial Eve" theory advanced eight
years ago.
 Scientists at the University of California at Berkeley said then that all
people descended from one African woman, basing their finding on tracking of
mutations in an original molecule of DNA, the genetic blueprint contained in
every living thing.
 In every DNA molecule, there are some 6 billion bits of information. Most of
these bits are in the molecule's heart, or nucleus, but about 15,000 of them are
outside the nucleus, in an area called the mitochondrion. This mitochondrial DNA
is passed only from mothers to children, and the Berkeley team used this to find
the woman they say gave all current humans this part of her DNA, which mutated
down through the ages.
 They theorised that she lived 100,000 to 200,000 years ago and while she was
not the only woman to have children then, her genes were the only ones that
endured to the present day.
 But Francisco Ayala, a professor of biological sciences at the University of
California at Irvine, used mathematical models to argue that this could not have
happened.
 "I find the ancestral molecule for an important piece of DNA that deals with
the immune system," he said in a telephone interview. "That molecule existed 60
million years ago, about when the dinosaurs became extinct, before the
origination of modern monkeys, let alone humans."
 Ayala, the author of the study being published in Science, calculated that
for all the variants of this immune system gene to have survived until now would
have required a population of at least 100,000.
 Some scientists say the one true Eve was possible because at times of great
anatomical change there is a population bottleneck -- fewer people. But Ayala
said through all the big anatomical changes, from the time of the earliest
monkeys until now, "there were no population bottlenecks at any time of our
ancestral species."
 The theory of mitochondrial Eve has sometimes been used to argue that the
differentiation between races was rather recent in evolutionary terms, but Ayala
disputed this notion, saying this differentiation was more likely to have
occurred around 1.8 million years ago when early humans began leaving Africa for
Europe and Asia.
 And what about Adam? Scientists reported in the British scientific journal
Nature this month that "Y-chromosome Adam" probably lived 188,000 years ago. The
Y-chromosome is passed only from fathers to children, just as mitochondrial DNA
is passed only from mothers.
===================
Dog finds dinosaur bone on British beach
 LONDON, Dec 22 (Reuter) - A dog has dug up a 118 million-year-old dinosaur
bone on a British beach.
 Jake, a bull terrier, discovered the fossilised arm bone of an iguanodon
while out walking with his owner John Winch on a beach on the Isle of Wight off
the English south coast.
 Both posed proudly with their find for the British media on Friday with Jake
dwarfed by the bone that is twice his size.
 "It is an interesting specimen because it is very well preserved and because
complete bones of any dinosaur are quite rare," Steve Hutt, curator of the Isle
of Wight Geological Museum, told the Daily Telegraph.
 The plant-eating iguanodon, which weighed up to four tonnes, was one of the
earliest dinosaurs to roam the earth.
===================
NEWT GINGRICH can't be all bad. He has an epoxy cast of a T-rex skull
in his office. (Must be where all of those book royalties went.)
The photo says it is "Tyrannosaurus rex Osborn" from the Hell Creek
formation.
===================
While most of the Stegosaurs were mid-Jurassic (160-140mya)
a couple of them lasted later....
Wuerhosaurus 125-110mya
Craterosaurus 115-105mya
and one of them hung in there to the VERY end of all dinos....
Dravidosaurus, a pygmy species, lived on in India (then a
free-floating island with no nodo/ankylosaurs) until the rock fell.