[ad_1]
The Italian Crested Newt – Triturus carnifex – Eat everything and anything that he can master. Earthworms, mosquito larvae and water fleas are on the menu, as well as snails, small fish and even their own offspring. A research team led by Dr. Egon Heiss of the Friedrich Schiller University in Jena (Germany) has studied the mating behavior of the newt and made an astonishing discovery.
Triturus carnifex is an amphibian of the order Caudata and a real salamander. "According to school textbooks, amphibians swallow their prey in full, but we have been able to refute that," says Heiss. In collaboration with doctoral student Daniel Schwarz and Dr. Nicolai Konow of the University of Massachusetts, Heiss has successfully demonstrated that crested newts actually chew their prey, but in a manner different from that of most Terrestrial vertebrates. The researchers have now presented their results in the specialist publication Journal of Experimental Biology.
Palatal teeth kill prey
"This newt uses what is called palatal teeth to kill prey but also to break it," says Heiss. This means that the teeth of the jaw are mainly used to catch or hold prey. With the help of the tongue, the prey is then rubbed rhythmically against the palate. The mouth has very sharp teeth, about 0.5 to one millimeter long, which are constantly replaced by new teeth. These teeth can, for example, tear the extremely resistant cuticles of maggots. "It kills the prey and, at the same time, helps the digestive secretions to act," says Heiss. For the newt, it is also a form of life insurance: some insect larvae have a bite so strong that they would be able to pierce the body of the predator . The first surprising research results appeared during a research visit to Antwerp (Belgium), when Nicolai Konow and Egon Heiss observed a newborn baby feeding. Biologists have been intrigued by the movements of the head, jaw and tongue of the amphibian after catching its prey. "The newt seemed to be actually chewing," Heiss said. The researchers were able to get a clear idea of what was going on with the help of the X-ray video unit of the Institute of Zoology and Evolutionary Research of the University of Jena.
Salamanders chew like primitive terrestrial vertebrates
The chewing behavior of the triton raises the question of how it can be explained in the context of evolution. "We can assume that the true palatal teeth were present in the first terrestrial vertebrates, and we suspect that the mechanism of chewing" tongue against palate ", as in the tritone, goes back to the beginnings of terrestrial vertebrates," he says. . Heiss. Very similar mastication mechanisms can indeed be found in ancient mammals such as echidna and duckbill, but also in the manatee. Although in these animals the palatal teeth have been replaced by rough structures of keratin, the creatures are still rubbing their food against the palate.
The language has its origin when vertebrates arrived on the mainland
From the point of view of evolution, the passage of water to the land has resulted in a change of animal chewing apparatus. A key role is played by language, which only developed after vertebrates left the water. It is crucial to allow chewing because it moves food to the right place in the mouth. "With the fish, the stream of water contributes to it," says Heiss. A similar change occurs in amphibian larvae; during metamorphosis, the gills of amphibians turn into tongues when the larvae leave the water.
The results presented are the first results of the research project "Form, function and evolution of food handling in Urodela", funded by the German Research Foundation (DFG) and launched in early 2017. end of 2019 and perhaps during this period. period, Triturus carnifex will be persuaded to reveal more secrets.
Source of the story:
Material provided by Friedrich-Schiller-Universitaet Jena. Note: Content can be changed for style and length.
[ad_2]
Source link