Food transforms domestic dogs | Country News
Dogs may share the same ancestor, but their life with people has led to considerable variation with modern dogs – one of the most variable species on the planet, in terms of size and proportions.
The shape of the mandible (the lower jaw) is influenced by the mechanical action of the jaw muscles which connect it to the skull, and the shape of the mandible therefore reflects the diet of the animal.
The lower jaw is also robust enough to survive burial and fossilization, providing valuable insight into the diet of long-dead animals.
A new international study has described the shape of 525 ancient dog mandibles from European archaeological sites. The study compared these 5,000-10,000-year-old remains to a reference sample of modern Australian dogs, wolves and dingoes.
“Ancient dogs are physically distinct from those of modern dogs, with the main differences in the curvature of the body under the carnassial (cutting) tooth suggesting that they fed on tougher and tougher foods than most modern dogs. “, lead author of the study, said Dr. Colline Brassard.
Modern dogs have an omnivorous diet. They have multiple copies of the amylase gene which increases their ability to digest starch – the carbohydrate found in plants such as cereals – a trait that has been interpreted to reflect their life alongside humans and the consumption of anthropogenic foods.
Dr Brassard said it was likely that the shift from a carnivorous to an omnivorous starch-containing diet of modern domestic dogs could explain the changes evident in the shape of their jaws.
“Somewhat surprisingly, the shape of dingo mandibles did not cluster with ancient dogs but was rather intermediate between wolves and modern dogs,” said Trish Fleming, a professor at Murdoch University, who collaborated to the works.
The dingo was introduced to Australia around 3600 to 5000 years ago and lived in isolation until around 200 years ago when Europeans brought modern dogs to the continent.
Dingoes have a carnivorous diet, with their main diet being kangaroos and wallabies, and they have recently been shown to have a single copy of the amylase gene, confirming their separation from the modern canine line before this adaptation. on an omnivorous diet.