Let it go!
(thanks to Kevin)
Pharyngula
Evolution, development, and random biological ejaculations from a godless liberal
I’m taking it easy here in the fabulous Van Dusen mansion, a bed and breakfast where I’m staying tonight, and I thought I’d browse through the stem cell legislation that’s being considered in the senate right now. It’s strange: one substantive bill has come up from the House, and all of a sudden two more bills have been proposed on the floor of the Senate.
I’ve made it to St Paul and am sucking down some caffeine before strolling over to the venue for my talk this afternoon, and I’ve got a few minutes for a quickie link dump from the mailbag. Digest these for a while…
Do vertebrate embryos exhibit significant variation in their early development? Yes, they do—in particular, the earliest stages show distinct differences that mainly reflect differences in maternal investment and that cause significant distortions of early morphology during gastrulation. However, these earliest patterns represent workarounds, strategies to accommodate one variable (the amount of yolk in the egg), and the animals subsequently reorganize to put tissues into a canonical arrangement. Observations of gene expression during gastrulation are revealing deeper similarities that are common in all deuterostomes—not just vertebrates, but also the invertebrate chordates (tunicates and cephalochordates) and echinoderms.
What does all that mean? If you think of development as a formal dance, the earliest stages are like the prelude; everyone is getting out of their chairs around the ballroom, looking for partners and working their way towards the floor. The dispositions of the dancers are variable and somewhat chaotic, and vary from dance to dance. Once they get to their positions, however, we’re finding that not only is there a general similarity in their arrangements, but they’re all dancing to the very same tune. In this case, one of the repeated motifs in that tune is a gene, Nodal, which is active in gastrulation and shows a similar pattern in animal after animal.
We’re getting rude, we dare to criticize the theistic evolutionists, and now Ophelia has done gone and poo-pooed the distinction between methodological and metaphysical materialism. I love it! Rise up, all ye fierce and firebreathing atheists!
Much as I’d enjoy the squeals of agony from the usual protesters, I’m going to suggest that you might be better off arguing over it at Ophelia’s. I’m doing a bit of traveling over the next two days, my access to the net might be spotty, and so I’ll probably be slow to approve any comments that our annoying spam filters might hold up.
They even show up on the weather radar. I think a weather report that predicted a chance of buzzing clouds of arthropods would be cool.
Because if there were no anthropocism contest, I wouldn’t be able to enter it.
(via Uncertain Principles)
The next Tangled Bank (#58) is coming up on Wednesday, 19 July, at Salto Sobrius. Have you sent in a submission yet? Mail links to your science weblog entries to Martin Rundkvist or [email protected] or me by Tuesday.
John Bentley sent me an issue of Seven Days with this interesting illustration on the cover: it’s titled “California”, by Chris Varricchione. Excuse the smudginess, but I just scanned it in from newsprint, so it isn’t exactly the cleanest image to start with. Still, I had to make it my desktop image—who can resist a flying mollusc/bird chimera? Now if only someone would point me to a sharper original source…
Thanks, John!
I’m going to be giving a talk tomorrow and Tuesday in St Paul and Minneapolis—if you’re free at the noon hour, stop on by! The title of the talk is “Science and Secularism in a Demon-Haunted World,” and it’s sponsored by the Atheists for Human Rights.
On Monday at noon I’ll be at the St Paul Landmark Center, 75 West Fifth Street, in the Ramsey County Room.
On Tuesday at noon I’ll be in the Minneapolis Downtown Public Library, in the Robins Kaplan Miller & Ciresi Room.
If you aren’t in the Twin Cities area, be patient…I just agreed to do an interview with the Infidel Guy sometime in August, so you might be able to hear me over your computer then.
