Evidence for a single loss of mineralized teeth in the common avian ancestor.
Abstract
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.
Type
Journal articleSubject
Alligators and CrocodilesAnimals
Biological Evolution
Birds
Dental Enamel
Dentin
Evolution, Molecular
Fossils
Genome
Genomics
Mammals
Mutation
Phylogeny
Tooth
Vertebrates
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https://hdl.handle.net/10161/11152Published Version (Please cite this version)
10.1126/science.1254390Publication Info
Meredith, Robert W; Zhang, Guojie; Gilbert, M Thomas P; Jarvis, Erich D; & Springer,
Mark S (2014). Evidence for a single loss of mineralized teeth in the common avian ancestor. Science, 346(6215). pp. 1254390. 10.1126/science.1254390. Retrieved from https://hdl.handle.net/10161/11152.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Erich David Jarvis
Adjunct Professor in the Dept. of Neurobiology
Dr. Jarvis' laboratory studies the neurobiology of vocal communication. Emphasis is
placed on the molecular pathways involved in the perception and production of learned
vocalizations. They use an integrative approach that combines behavioral, anatomical,
electrophysiological and molecular biological techniques. The main animal model used
is songbirds, one of the few vertebrate groups that evolved the ability to learn vocalizations.
The generality of the discoveries is tested in other vocal

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