systematics
awild | December 3, 2009Here's an issue that's been on my mind as I'm shuffling trees around from several concurrent phylogenetic projects.
The primary output from phylogenetics programs is tree diagrams depicting the relationships among organisms. Very clean, very crisp, very precise diagrams. Precision isn't in itself a problem, but for the human foible of mistaking precision for accuracy.
I'm not interested in a precise estimate of evolutionary history so much as a correct one. I'm reminded as much when I see my estimates change from one precise conclusion to another as I add more data from more species. …
grrlscientist | December 24, 2008tags: parrots, Psittaciformes, evolution, molecular phylogeny, ornithology, Neornithes
Red-crowned Amazon parrot, Amazona viridigenalis, at Elizabeth Street Parrotry, Brownsville, Texas.
Image: Joseph Kennedy, 7 April 2008 [larger view].
Nikon D200, Kowa 883 telescope TSN-PZ camera eyepiece 1/750s f/8.0 at 1000.0mm iso400.
One of the most contentious issues among scientists who study the evolution of birds is identifying precisely when the modern birds (Neornithes) first appeared. This is due to conflicts between the fossil record and molecular dating methodologies. For example, fossils…