What it is like to make a bat

Sorry, philosophy fans, I'm not riffing off Nagel here. Instead, let me link you to that rat bastard Paul Mhgfs, who has another of his wonderfully written pieces on development and evolution in "How to make a bat" on Pharyngula - the second best science blog after the Journal of Irreproducible Results.

Myliz, whose name is unaccountably impossible to spell, makes a number of points about how bats evolved flight. In the process he notes that it is a mistake to think that

the genome encodes a blueprint of morphology. It doesn't; what it contains is a description of interacting agents that work together in a process to produce a complex result. Changes in genes and regulatory elements can essentially produce changes in rules of development, rather than crudely specifying blocks of morphology.

Amen, brother! Mahrz also notes that the growth of finger bones is relatively easy to achieve - just keep early cells in bone growth, regulated by the Bmp2 gene, dividing for longer. Of such variation, easy to generate by additional copies or underregulation of the gene, is natural selection able to make new morphologies. If you happen to be laboring under the misapprehension (or in Bushese, misundertaking) that genes are instructions, go read this.

I wish I could write like him. The bastard. In fact, I wish I were him, only I'd change my name.