Freitag, 13. Juli 2007
Taking an axe to the tree of life
klauslange,13:21h
Ein interessanter Artikel über eine alternative Sichtweise aus der Universität Dalhousie:
http://dalnews.dal.ca/2007/07/11/evolution.html
Daraus:
Charles Darwin’s famed Tree of Life hypothesis limits and even obscures the study of organisms and their ancestries, according to a group of Dalhousie molecular biologists. What’s the danger in believing that all beings of the same class, living and extinct, derive from a single figurative “tree” and its branches?
“It’s not true, that would be the main danger. It misleads us,” says Ford Doolittle, Dalhousie’s Canada Research Chair in Comparative Microbial Genomics.
...
Current research is finding a far more complex scenario than Darwin could have imagined, particularly in relation to bacteria, archaea and one-celled organisms. These simple life forms represent most of the earth’s biomass and diversity, not to mention the first two-thirds of the planet’s history. Many of their species swap genes back and forth, or engage in gene duplication, recombination, gene loss or gene transfers from multiple sources.
Dr. Doolittle and postdoctoral fellow Eric Bapteste highlight these varied genetic pathways and propose alternative tools and models in their paper, “Pattern pluralism and the Tree of Life hypothesis,” published in a recent PNAS journal, by the National Academy of Sciences of the United States of America. (Dr. Bapteste just picked up his second PhD, in Philosophy, from the Sorbonne.)
...
“People were born to classify things. It’s a natural and useful human practice,” says Dr. Doolittle. But such focus on building historical hierarchies based on outmoded assumptions can get in the way of real science and discovery, he stresses.
That’s not the case at Dalhousie, which has gained a reputation as one of the world’s leading centres of excellence in molecular evolutionary biology through work by Dr. Doolittle and Drs. Michael Gray, John Archibald, Andrew Roger and other researchers in the Department of Biochemistry and Molecular Biology, plus at least a dozen colleagues in Biology, Mathematics and Statistics and Computer Science. It’s still a relatively young field of study, emerging with the discovery of DNA structure in the 1950s.
http://dalnews.dal.ca/2007/07/11/evolution.html
Daraus:
Charles Darwin’s famed Tree of Life hypothesis limits and even obscures the study of organisms and their ancestries, according to a group of Dalhousie molecular biologists. What’s the danger in believing that all beings of the same class, living and extinct, derive from a single figurative “tree” and its branches?
“It’s not true, that would be the main danger. It misleads us,” says Ford Doolittle, Dalhousie’s Canada Research Chair in Comparative Microbial Genomics.
...
Current research is finding a far more complex scenario than Darwin could have imagined, particularly in relation to bacteria, archaea and one-celled organisms. These simple life forms represent most of the earth’s biomass and diversity, not to mention the first two-thirds of the planet’s history. Many of their species swap genes back and forth, or engage in gene duplication, recombination, gene loss or gene transfers from multiple sources.
Dr. Doolittle and postdoctoral fellow Eric Bapteste highlight these varied genetic pathways and propose alternative tools and models in their paper, “Pattern pluralism and the Tree of Life hypothesis,” published in a recent PNAS journal, by the National Academy of Sciences of the United States of America. (Dr. Bapteste just picked up his second PhD, in Philosophy, from the Sorbonne.)
...
“People were born to classify things. It’s a natural and useful human practice,” says Dr. Doolittle. But such focus on building historical hierarchies based on outmoded assumptions can get in the way of real science and discovery, he stresses.
That’s not the case at Dalhousie, which has gained a reputation as one of the world’s leading centres of excellence in molecular evolutionary biology through work by Dr. Doolittle and Drs. Michael Gray, John Archibald, Andrew Roger and other researchers in the Department of Biochemistry and Molecular Biology, plus at least a dozen colleagues in Biology, Mathematics and Statistics and Computer Science. It’s still a relatively young field of study, emerging with the discovery of DNA structure in the 1950s.
... comment
