Why some animals have protruding noses: the study

This is an ancient transition from a reptile-like structure. The origin of typical mammalian facial bones has been revealed.

Most mammals have protruding, flexible noses. A team of researchers has unveiled the origin of this particular facial conformation of some animals and humans. The study was carried out by an international group led by the University of Tokyo and the research was published in Proceedings of the National Academy of Sciences. This is the first analysis of the evolution of facial structure using cellular studies comparing multiple embryos of multiple species. The observation starts by comparing fossil ancestors of both reptiles, for example snakes, and four-legged animals. These beings had the same number of upper jaw bones, then there would be a different evolution that led to the formation of the protruding nose in mammals.

The study on the protruding nose of some animals

Researcher Hiroki Higashiyama, from the Graduate School of Medicine at the University of Tokyo, explained that the number of bones between reptiles and mammals is probably the same "but now we can study embryos and monitor cell development to study these bones in much more detail." According to the study, the tip of the jaw in reptiles is formed by a group of cells, called the frontonasal prominence, which later became the protruding nose in mammals. Species, over time, have accumulated a large number of physical and genetic differences, but observations of the facial bones of egg-laying mammals, such as the Australian platypus and echidna, have provided some living examples of transitional bone structures from the evolutionarily older reptile model to the more recent mammalian structure.

Application of the discovery in science

The discovery helps to better understand the origin of the strong mammalian sense of smell and may be useful in devising experiments investigating facial developmental disorders such as cleft palate. The separation of the nose and jaw gives mammals their ability to "smell," using muscles to dilate the nostrils and inhale deeply odors from the environment. According to Higashiyama, the composition of facial protuberances and embryonic development in multiple species makes it possible to compare disorders of facial development and better understand their causes.

About the animal world, there are many studies and mysteries to be unraveled. Recently it has been found that dinosaurs were social beings, while the most dangerous bird in the world was domesticated by men even before chickens.

Stefania Bernardini