A recent research has shown that the method of chewing the food in mammals and fish is not the same. Fish make use of tongue muscles to push the food in the back direction, while mammals use it to keep the food in place for grinding. According to the scientists from Brown University, this difference in the way to chew depicts animals have altered the method to chew and digest food also that development also has a part in this.

They drew a result that deviation in development was most likely happened with amphibians.

“It’s pretty clear that all of these animals chew, but the involvement of the tongue in chewing differs,” said Nicolai Konow, a postdoctoral researcher at Brown and the lead writer on the study.” And that brings up the question of what the muscles associated with the tongue and the jaw are doing,” he added.

Konow and his group researched the role of muscles of three mammals alpacas, goats and pigs in chewing. They prepared with electrodes fixed in the jaw and tongue muscles to recognize movement of each set of muscles while chewing. The study showed that the tongue of animals pushes forward and upward as they start chewing and after that it went back to its original position. It was also evident that when the animals faced left, the tongue makes an ellipse shape in a counter-clockwise direction for each time.

When the fish faces left, the chewing cycle gives an impression of ellipse shape tilted at an angle, while tongue makes a movement in a clockwise direction.

The previous researches reveal that while chewing, fish shoots off the muscle known as sternohyoid taking back the tongue inward, before making it move again forward and upward, to its original position in the upper mouth. “We think the herbivore needs the bolus (the soft mass of chewed food) to be in a precise place between each chew. So the tongue may be constantly moving around to make sure the bolus is in the right place between chews”, Konow explained. The research has been printed in the journal of Integrative and Comparative Biology.