Scientists from UCL and the University of Hull demonstrated with a computer model of how the New Zealand tuatara reptile chews its food in a steak knife way.
Scientists thought that the only animals that were able to chew their food up so well were mammals. This new discovery shows it doesn’t take a high metabolism for complex chewing.
The scientists used a computer model developed at the University of Hull allowing the moving structures of the reptiles jaw to be studied in 3D and from all angles. (Watch Video Below)
The study published in the journal The Anatomical Record, the researchers used a computer model to show that when the tuatara reptile chews, the lower jaw closes between two rows of upper teeth. Once closed, the lower jaw slides forward to cut food between sharp edges on the teeth, which saws food apart.
Neil Curtis, co-author of the study from the University of Hull’s Department of Engineering said, “We developed this virtual model using software that is widely used in the analysis of complex engineering systems. It is the most detailed musculoskeletal model of a skull ever developed and demonstrates the huge potential of this type of computer modelling in biology.”
“It allows us to investigate movements within skulls that would be impossible to monitor in a live animal without using harmful X-rays which is not an option for protected species like the tuatara,” he added.
Marc Jones, lead author from UCL Cell and Developmental Biology said, “Some reptiles such as snakes are able to swallow their food whole but many others use repeated bites to break food down. The tuatara also slices up its food, much like a steak knife.”
“Because mammals show the most sophisticated form of chewing, chewing has been linked to high metabolism. However, the tuatara chews food in a relatively complex way but its metabolism is no higher than that of other reptiles with simpler oral food processing abilities. Therefore the relationship between extensive food processing and high metabolism has perhaps been overstated,” he added.
The tuatara reptile can provides an example in which specialisation of chewing can allow a broader diet.
“The slicing jaws of the tuatara allow it to eat a wide range of prey including beetles, spiders, crickets, and small lizards. There are also several grizzly reports of sea birds being found decapitated following predation by tuatara. Although the tuatara-like chewing mechanism is rare today, fossils from Europe and Mexico show us that during the time of the dinosaurs (about 160 million years ago) some fossil relatives of the tuatara used a similar system and it was much more widespread,” Jones said.