Frogs are one of our most common animals. Especially in the summer in the countryside, only where there is a water source, frogs can open a large-scale "concert". Frogs have long been considered "beneficial insects" (of course frogs are not bugs) because their main food is many insects that are harmful to humans. Usually, frogs hunt on their own retractable tongues, but there is a type of frog that does not have a tongue and rests on the "hand" (i.e., forelimbs).
Speaking of frogs, many people think that it is a general term for frogs. In fact, frogs are a general term for frogs and toads, that is, both frogs and toads belong to frogs. Frogs belong to large amphibians, there are more than 2500 different species of frogs in the world, although China is vast, but there are only about 130 species of frogs.
Both frogs and toads are strictly carnivores, and they do not have the sharp teeth and claws of land predators. However, their main diet is mainly small insects, so they do not need too strong teeth and claws, so frogs have evolved a retractable tongue.
When frogs hunt, their tongues will accurately hit the prey at an acceleration of 12 times the gravity, and the prey will be firmly "rolled" inside, and finally sent to the mouth.
All frogs have a common trait, which is that their growth is completely metamorphosed. Juvenile frogs are tadpoles, which go from oviparous to tadpoles (with tails) to tails that degenerate, appear limbs, and finally become frogs in their final form. And frogs are slender on all fours and good at jumping.
Among all frogs, different species have different characteristics and abilities. Because frogs do not have a large size and sharp claws and teeth, they have little ability to protect themselves, so in order to protect themselves, they have evolved different characteristics, such as skin color close to the environment, and some frogs are highly poisonous. For example, the poison dart frog is a frog that can secrete toxins, although its body length is only about 2 centimeters, but the poison dart frog is enough to kill 20,000 adult mice.
In Africa, there is a toad that is very different from other frogs, which has neither any means of self-preservation, nor a skin color that is different from its natural environment, or even a tongue. It's the African clawed frog.
The African clawed frog is a species of frog that lives in sub-Saharan Africa and belongs to the genus Clawed frogs of the subfamily Possumidae of the toad family Toadidae. Outwardly, the African clawed frog does not have the ugly appearance of other toads, on the contrary, its appearance is even more beautiful than that of frogs.
The African clawed frog has a solid skin (mainly yellowish), and the lighter skin color makes it look very "crystal clear", so the African clawed frog is fed as a "pet" by many people.
The special hunting method of the African clawed frog
Frogs are mostly uniform and simple in their hunting style, usually they can stand motionless in one place, and when insects pass by, once they reach the hunting range, their tongues will be launched like springs to hunt prey.
However, unlike the African clawed frog, it does not have a tongue. As one of the few tongueless frogs, the African clawed frog also needs to catch insects for food, so how does it do it?
The African clawed frog has a distinct feature, that is, the two claws of its forelimbs are different from other frogs, it has two pairs of pale black sharp claws (three on each forelimb), and these two pairs of claws are its hunting tools. In order to maximize the effectiveness of its claws, it has evolved to have stronger hind limb strength than other frogs. When it finds prey, it will use its strong hind legs to launch itself into the position of the prey, and then use the claws of its two forelimbs to firmly "hold" the prey, and then use the two forelimbs to send the prey into its mouth (I actually have the visual sense of "Principal Wang eating hot dogs").
This means that the African clawed frog is the only animal in the frog species that hunts with its "hand". But is the ability of the African clawed frog limited to this? Of course not!
Clawed frogs prey on small fish
Most of the natural enemies of frogs are snakes and birds. In juvenile life, that is, in the state of tadpoles, they have fewer natural enemies, mainly fish, but after all, frogs are very capable of reproduction, and even fish are mostly cichlids that eat tadpoles and eggs. Therefore, relatively speaking, the natural enemies of tadpoles are relatively small.
However, you may not think that frogs also eat tadpoles as well as eggs. Of course, this type of frog is very rare, and one of them is the African clawed frog.
The African clawed frog can accurately distinguish its own eggs from other eggs of the same kind, and it will eat a large number of tadpoles and eggs of other frogs. This has been confirmed.
Many people bring the African claw frog to South Africa to be raised as an ornamental frog. Seeing this, many friends will have questions, is not the African claw frog above living in the sub-Saharan Desert? Isn't that South Africa? In fact, the Sahara Desert is located in the northwest of Africa, and its southern part is not South Africa.
Locals put the African clawed frog in ponds, but they found that after a while, the other frogs in the waters almost disappeared, which made many of South Africa's native frogs, such as cape platann, "worse".
To figure out why, Dr. John Measey of Stellenbosch University in South Africa did the following experiment:
He first placed the African clawed frog in a series of tanks containing different tadpole species. After placing the African claw frog in a tank with the cape platanna tadpole, the team found that the African claw frog did have a habit of eating the offspring of other frogs, and that the African claw frog preferred to eat the offspring of its endangered cousins (that is, the descendants of the Gil clawed toad).
The discovery revealed the true face of the African clawed frog. That said, the African clawed frog is indeed a "nightmare" of its kind.
The fact that a homogeneous living on the same continent could become a natural enemy of the same kind was something that no one had ever imagined before. Since the discovery of the habit of the African clawed frog, many parts of South Africa have banned the breeding of this frog and its release has been strictly prohibited.
I didn't expect that this kind of frog, which looks "harmless to humans and animals" on the surface, and even a little cute, is so "cold-blooded". In fact, in recent years, examples of local ecological damage caused by animals released due to insufficient understanding of animals abound. In the south of our country, a fish that could have been cleaned in the fish tank , the scavenger , has been mistakenly placed in the local waters and has caused a significant reduction in many fish.
This is officially "invasive species" of harm. So, don't think that the release is saving the animal, it is likely that your good intentions will cause serious consequences.