Convergent evolution
edyong | March 14, 2010Take a whiff of mustard or wasabi and you'll be hit with a familiar burning sensation. That's the result of chemicals in these pungent foods hitting a protein called TRPA1, a molecular alarm that warns us about irritating substances. The same protein does a similar job in other animals, but rattlesnakes and vipers have put their version of TRPA1 to a more impressive and murderous purpose. They use it to sense the body heat of their prey.
Pit vipers are famed for their ability to detect the infrared radiation given off by warm-blooded prey, and none more so than the western diamondback…
grrlscientist | January 30, 2010tags: evolutionary biology, convergent evolution, paleontology, taxonomy, zoology, basal birds, theropods, dinosaurs, ornithology, birds, Alvarezsauroidea, Haplocheirus sollers, Maniraptora, Archaeopteryx, researchblogging.org,peer-reviewed research, peer-reviewed paper
A Newly Discovered Basal Alvarezsauroid Theropod from the Early Late Jurassic.
Artwork: Portia Sloan [larger view]
DOI: 10.1126/science.1182143
A long-standing scientific debate focuses on the origins of birds: did they evolve from reptiles or dinosaurs? Currently, most scientists think that birds are modern dinosaurs,…
razib | January 25, 2010In Bats and Whales, Convergence in Echolocation Ability Runs Deep:
..."However, it is generally assumed that most of these so-called convergent traits have arisen by different genes or different mutations. Our study shows that a complex trait -- echolocation -- has in fact evolved by identical genetic changes in bats and dolphins."
A hearing gene known as prestin in both bats and dolphins (a toothed whale) has picked up many of the same mutations over time, the studies show. As a result, if you draw a phylogenetic tree of bats, whales, and a few other mammals based on similarities in the…
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…