Evidence for a single loss of mineralized teeth in the common avian ancestor
MetadataShow full item record
Edentulism, the absence of teeth, has evolved convergently among vertebrates, including birds, turtles, and several lineages of mammals. Instead of teeth, modern birds (Neornithes) use a horny beak (rhamphotheca) and a muscular gizzard to acquire and process food. We performed comparative genomic analyses representing lineages of nearly all extant bird orders and recovered shared, inactivating mutations within genes expressed in both the enamel and dentin of teeth of other vertebrate species, indicating that the common ancestor of modern birds lacked mineralized teeth. We estimate that tooth loss, or at least the loss of enamel caps that provide the outer layer of mineralized teeth, occurred about 116 million years ago.
Showing items related by title, author, creator and subject.
Rucklin, M.; Donoghue, P.; Johanson, Z.; Trinajstic, Katherine; Marone, F.; Stampanoni, M. (2012)Teeth and jaws constitute a model of the evolutionary developmental biology concept of modularity and they have been considered the key innovations underpinning a classic example of adaptive radiation. However, their ...
The effects of reducing bird predation on canopy arthropods of marri (Eucalyptus calophylla) saplings on the Swan Coastal Plain, Western AustraliaEvelegh, N.; Majer, Jonathan; Recher, H. (2001)The effect of bird predation on canopy arthropods inhabiting Marri (Eucalyptus calophylla) saplings was examined in Banksia woodland on the Swan Coastal Plain of Western Australia. Twenty pairs of saplings were selected ...
Of toothy grins and angry snarls-open mouth displays contribute to efficiency gains in search for emotional facesHorstmann, G.; Lipp, Ottmar; Becker, S. (2012)The emotional face-in-a-crowd effect is widely cited, but its origin remains controversial, particularly with photorealistic stimuli. Recently, it has been suggested that one factor underlying the guidance of attention ...