molecular phylogeny
grrlscientist | January 27, 2009tags: evolution, speciation, diversification rate, Zosterops, White-eyes, ornithology, birds, molecular phylogeny, South Pacific Islands
The Splendid (Ranongga) White-eye, Zosterops splendidus,
endemic to Ranongga Island in the Solomon Islands archipelago.
This species' home range is smaller than Manhattan Island.
Image: Chris Filardi [larger view].
For many decades, the white-eyes (Family: Zosteropidae) were known as the "Great Speciators" in honor of their apparent ability to rapidly give rise to new species while other birds in the same areas showed little or no diversification. But…
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…
grrlscientist | December 15, 2008tags: evolution, honeyeaters, Meliphagidae, Mohoidae, birds, ornithology, birds, molecular phylogeny, extinct species, South Pacific Islands
Two nectar-feeding birds from Hawai'i, the kioea (brown-streaked, in middle) and an o'o species (lower left), looked so much like nectar specialists from the western Pacific (two species on right) that taxonomists put them all in the same honeyeater family, the Meliphagidae. All the Hawaiian birds are unfortunately extinct, but DNA evidence shows that their resemblance resulted from convergent evolution, because the Hawaiian birds were actually much…
grrlscientist | December 22, 2007tags: researchblogging.org, giraffe species, Giraffa camelopardalis, speciation, evolution, conservation, molecular phylogeny
West African giraffe, currently Giraffa camelopardalis peralta.
Image: Wikipedia (Creative Commons) [larger view]
How many species of giraffes are there? Well, it may surprise you to learn this, but some people have actually thought about this throughout the decades, and they decided that there is only one species, Giraffa camelopardalis. However, a paper published today in BMC Biology convincingly demonstrates that giraffes are actually comprised of at least six…