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Video: Amphibian Behavior
Amphibians are quite calm animals. Their behavior cannot be compared to that of cobras or rattlesnakes. They can't stand on their hind legs and run on water like basilisks. They can't even hide in themselves like turtles. But they also have very interesting behavioral features.
Pond frog (Pelophylax lessonae)
Amphibians can change their color. This can be caused by light levels, temperature, background color (not for all species) and stress. The color changes thanks to special cells - chromophores, which are contained in the dermis and epidermis.
The speed and reversibility of color changes, which are called physiological changes, are provided by the intracellular movement of pigment-containing organelles within the chromatophore. An example of such rapid changes is the yellow-spotted tree frog (Hyla punctata) living in the Neotropics. During the day, the tree frog is pale green in color with a yellow stripe on the sides and yellow spots on the back. At night, the yellow color gradually disappears and red appears in its place, giving the back a reddish-brown tint.
Slow color change refers to morphological change. It is caused by the destruction of one and the formation of another pigment in chromatophores. Through this process, amphibians darken with age.
Amphibians are aware of what is happening around them thanks to their skin, which contains nerve endings that send messages about the environment to the brain. The dermis contains many nerve fibers, some of which penetrate the epidermis. Here they serve as receptors for the perception of heat, cold, pain and pressure.
Some amphibians have significantly better skin sensing systems. This is the lateral line system found in aquatic amphibians such as amphium, Alleghenian burrowing gibber, and siren. The lateral line system contains both mechanoreceptors (neuromasts) and electroreceptors.
These cells allow amphibians not only to detect movement in the water, but also to understand what exactly caused this movement.
If the movement of the water is caused by the presence of an animal, the lateral line can identify it using an electric field. Even if the amphibian could not recognize what kind of animal it was, at least it would not be caught off guard.
Amphibians can be aggressive. Perhaps the most aggressive is the fist-sized, ivory-colored horned frog with brown spots. She hides in the foliage of trees growing in the South American jungle - her habitat. When something edible (insect, small mammal, bird or other frog) appears nearby, the horned frog grabs the prey with its giant mouth. Its jaws are so strong that they grind the bones of a mouse, and on the jaw there are two bony outgrowths that prevent the prey from freeing. All in all, the slingshot bite is quite impressive.
Other toads, such as the Cameroon toad (Bufo superciliaris) and the Rococo toad (Rhinella schneideri), defend against enemies by combining toxic skin secretions and head butting. They tilt their heads and rush at the enemy, pressing the parotoid glands that produce the toxin to his body. This is a pretty effective deterrent.
The tiger salamander and newts secrete the substance from the pores located on the back, and use their tail to spray it on the attacker. He rebounds and leaves the battlefield, which was required. But raccoons are smart enough to flip a salamander or newt, wait for the secretion to run out, then clean it off and: the amphibian becomes a link in the food chain.
Amphibians and their care for offspring
Some amphibians take care of their clutch. For example, a female pipa carries eggs on her back. The skin on the back swells and stretches, forming a pouch around each egg. Depending on the species, the tadpoles either hatch and swim away, or undergo a process called direct metamorphosis in this sac on the back of the toad and are born as tiny copies of adult animals.
In tree frogs, the female carries eggs in a special bag on her back. Babies hatch either by completely copying an adult, or in the form of tadpoles, depending on the type of frog.
Perhaps the most unusual way of caring for offspring is by swallowing eggs. This is what Australian toads do: nosed rheobatrachus (Rheobatrachus silus) and northern rheobatrachus (Rheobatrachus vitellinus). The female swallows the fertilized eggs and the tadpoles develop inside her stomach. She then opens her mouth, dilates her esophagus, and regurgitates juveniles from her stomach. Only then can the female start feeding again.
Some salamanders have an extremely developed ability to orientate in space. They not only know how to navigate the stars and the moon, but also sense the time of day, and therefore know exactly when to look for these celestial bodies. If a giant salamander is carried 8 km from its habitat, it can find its way back. She is helped by sense of smell, orientation by the stars, etc. This is all called kinesthetic orientation. It is also noteworthy that amphibians can sense the currents of magnetic waves like migratory birds. The pineal gland plays a major role in the art of star orientation. Interestingly, amphibians can return to their native reservoir even in inclement weather, when visual orientation by the stars is impossible.