The Tree of Life

I'm off to a meeting on Perspectives on the Tree of Life.¹ (See Perspectives on the Tree of Life: Day One, Day Two, Day Three.)


If you want to follow the real scientific debate on the tree of life then read my earlier posting on The Three Domain Hypothesis especially the one on "The Web of Life."

The basic idea is that there is no strict branching tree of life that accounts for the data during the early stages of life on Earth. The first group of single-cell organisms exchanged genes so frequently that the gene phylogeny looks much more like a jumbled web that a traditional tree.

You should also listen to Ford Doolittle's talk on The Tree of Life. If you have any questions you'd like to ask, post them here and I'll bring them up at the meeting.

This part isn't very controversial. There really are good evolutionary biologists who are questioning the tree of life. It's just part of the gradual undoing of the Three Domain Hypothesis in light of the enormous amount of data refuting it.

What's controversial is the rejection of the very concept of trees in evolutionary biology and that's where the philosophers come in. This meeting has a 50:50 mixture of philosophers and scientists. It's gonna be fun.

Do you remember what was wrong with the New Scientist story last winter? It wasn't that scientists were questioning the tree of life 'cause that part of the story is quite accurate. What upset me was the fact that New Scientist exploited Charles Darwin by tying him to the idea that early bacterial evolution was treelike when, in fact, he knew nothing at all about the subject.

How could he have been wrong when he never wrote a thing about the relationship between various divisions of bacteria and archaebacteria and their affinities with eukaryotes?

The other thing that bugged me was that this story wasn't new but New Scientist played it up as a new discovery.

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1. The original title of the meeting was "Questioning the Tree of Life" but it's been changed to more closely reflect the divergent opinions of the participants.