Here are some summaries from the most recent SCIENCE Online (I don't
have access to the main articles), which suggest big problems may
loooming for evolution:
1. PROKARYOTES MAY HAVE PREDATED EUKARYOTES!
http://www.sciencemag.org/cgi/content/summary/280/5364/673
EVOLUTION: Direct Descendants From an RNA World
Elizabeth Pennisi
The newly sequenced microbial genomes are challenging the consensus
that eukaryotes, organisms ranging from yeast to human that have
nucleated cells, evolved from archaea--one kingdom of nonnucleated
prokaryotes--rather than from bacteria, the other prokaryote
kingdom. Now a team of microbial evolutionary biologists suggests
in the January Journal of Molecular Evolution that eukaryote-like
cells actually predated the prokaryotes.
Volume 280, Number 5364, Issue of 1 May 1998, p. 673 (R) 1998 by The
American Association for the Advancement of Science.
Copyright (R) 1998 by the American Association for the Advancement
of Science.
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2. THE "TREE OF LIFE" MAY HAVE NO KNOWABLE ROOTS!
http://www.sciencemag.org/cgi/content/summary/280/5364/672
EVOLUTION: Genome Data Shake Tree of Life
Elizabeth Pennisi
The new wealth of microbial genome sequences is threatening to
overturn evolutionists' "tree of life." In the current tree, a
universal common ancestor gave rise to the two microbial branches,
the archaea and bacteria (which lack cell nuclei), and the archaea
then gave rise to the eukarya (all organisms that have cell nuclei).
But the new sequences show that genes don't evolve at the same rate
or in the same way, so the evolutionary history inferred from one
gene may be different from what another gene appears to show. Even
more perplexing, some genomes have been found to contain a mix of
DNAs from both the archaea and the bacteria. Many evolutionary
biologists are coming to believe that these mosaics arose because
genes hopped from branch to branch as early organisms either stole
genes from their food or swapped DNA with their neighbors. If this
gene swapping was extensive enough, the tree's "base" may turn out
to be indecipherable: a network of branches that merge and split
and merge again before sprouting the modern kingdoms.
Volume 280, Number 5364, Issue of 1 May 1998, p. 672 (R) 1998 by The
American Association for the Advancement of Science.
Copyright (R) 1998 by the American Association for the Advancement
of Science.
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3. MODERN ORDERS OF MAMMALS WERE UNDER WAY WELL BEFORE THE
DEMISE OF THE DINOSAURS
http://www.sciencemag.org/cgi/content/summary/280/5364/675
EVOLUTIONARY BIOLOGY: Genes Put Mammals in Age of Dinosaurs
Ann Gibbons
The long-standing view from the fossil record is that mammals first
appeared 225 million years ago as small, shrewlike creatures and
that only after a mass extinction 65 million years ago at the end of
the Cretaceous period killed off the dinosaurs were mammals able to
evolve into everything from primates to rodents to carnivores. But
in this week's issue of Nature, a pair of researchers compared genes
from hundreds of vertebrate species and used the differences as a
molecular clock to date when animal lineages originated. The
molecules show, they say, that the modern orders of mammals go back
well into the Cretaceous period, in some cases to more than 100
million years ago.
Volume 280, Number 5364, Issue of 1 May 1998, p. 675 (R) 1998 by The
American Association for the Advancement of Science.
Copyright (R) 1998 by the American Association for the Advancement
of Science.
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Stephen E (Steve) Jones ,--_|\ sejones@ibm.net
3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au
Warwick 6024 ->*_,--\_/ Phone +61 8 9448 7439
Perth, West Australia v "Test everything." (1Thess 5:21)
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