As we are so often reminded by proponents of Intelligent Design creationism, we contain molecular “machines” and “motors”. They don’t really explain how these motors came to be other than to foist the problem off on some invisible unspecified Designer, which is a poor way to do science—it’s more of a way to make excuses to not do science.
Evolution, on the other hand, provides a useful framework for trying to address the problem of the origin of molecular motors. We have a theory—common descent—that makes specific predictions—that there will be a nested hierarchy of differences between motors in different species. Phylogenetic analysis of variations between species allows us to reconstruct the history of a molecule with far more specificity than “Sometime between 6,000 and 4 billion years ago, a god or aliens (or aliens created by a god) conjured this molecule into existence by unknown and unknowable means”.
Richards and Cavalier-Smith (2005) have applied tested biological techniques to a specific motor molecule, myosin, and have used that information to assemble a picture of the phylogenetic history of eukaryotes.
Continue reading “Evolving motors” (on Pharyngula)
12 Comments
Frank J · 28 August 2005
Creationist Troll · 28 August 2005
KiwiInOz · 28 August 2005
CT - IMHO the similarity is striking. ;-)
steve · 28 August 2005
PvM · 28 August 2005
The thought had crossed my mind. "Father forgive them for they know not what they do" Luke 23:34-35
Schmitt. · 28 August 2005
Tim Chase · 29 August 2005
The Animal-Fungi Connection
While I am not familiar with MYTH4/FERM duplication, according to our current understanding, animals are more closely related to fungi than to plants -- so it would not be at all surprising if animals and fungi shared a gene duplications. And in fact, they do: three family B DNA polymerases (alpha, delta, and epsilon) which are responsible for replication of nuclear DNA, for example.
Jim Harrison · 29 August 2005
I don't know why our kinship with the fungi surprises anybody. We're also freeloaders, after all, while most of the plants, many of the prokaryotes, and even some protists photosynthesize or make a decent living as chemoautotrophs. I think of myself as a large portobello with legs.
carlhjones · 29 August 2005
I used to have a boss that had a cool poster on his wall. It had a large picture of a mushroom with a thought-balloon saying:
I must be a mushroom.
I MUST be a mushroom.
... everyone keeps me in the dark and feeds me s***
ts (not Tim) · 29 August 2005
Intelligent Design Theorist Timmy · 29 August 2005
My uncle weren't no Shiitake Mushroom.
Henry J · 29 August 2005
Re "I don't know why our kinship with the fungi surprises anybody. We're also freeloaders,"
Wonder if I should resemble that remark? :)
Actually though, that fungi were closer to animal than green plant did startle me when I first read it. But I guess that was mainly because when I was in school (60's-70's), the textbook sort of lumped everything into the two "kingdoms" - plant or animal. Ergo, I was taught back then that fungi were plants.
But granted, once somebody looks at how fungi get their nutrients, and compares that to green plants (that make a lot of their own) and animals (that disolve organic matter and absorb stuff from it), it makes sense.
Otoh, said relationship of us to fungi is way more distant than our relationship to worms, bugs, sponges, etc., so looking at it that way I don't see why somebody would worry overmuch about their relationship to fungi.
Henry