molecular clock

tags: evolutionary biology, speciation, species flocks, molecular phylogeny, behavioral ecology, Synodontis species, squeaker catfish, cuckoo catfish, Lake Tanganyika, peer-reviewed paper The Cuckoo Catfish, Synodontis multipunctatus [Siluriformes: Mochokidae]. This is the only fish that is a known brood parasite. This is one of the species included in this newly-published study. Image: orphaned. One of the groups of fishes that I worked with as an aquarist for nearly my entire life are the synodontids, often known as "squeaker catfish" for their ability to make high-pitched sounds. These…
tags: researchblogging.org, evolution, bird-dinosaur split, dinosaurs, birds, rocks-versus-clocks, fossil record, molecular clocks The first feathered dinosaur fossil found in China -- Sinosauropteryx. The feathers can be seen in the dark line running along the specimen's back. Image: Mick Ellison, AMNH [larger view] There is a lot of controversy among scientists regarding when modern birds first appeared. The current fossil record suggests that modern birds appeared approximately 60-65 million years ago when the other lineages of dinosaurs (along with at least half of all terrestrial…