The oral jaws of Pseudotropheus elongatus.

The oral jaws of Pseudotropheus elongatus.

The jaws of vertebrates, their origins, and their associated dentitions have long been a topic of interest among both paleontologists and evolutionary developmental biologists. The modern diversity of Lake Malawi cichlids has been used here to offer a new perspective on the relationships between teeth on two sets of functional jawsâ€"oral and pharyngealâ€"and the origins of the vertebrate dentition in the throat of jawless fishes some 500 million years ago (see Fraser et al., e1000031).