This animal is really unheard of, they will eat the fertilized eggs into the stomach, let them hatch in the stomach, and finally mature and then spit out the baby. They are the little frogs that live in the forests of Queensland, Australia, and scientists call them "Australian frogs", and a more figurative name called "stomach frogs", of course, can not be seen at present, because both kinds of stomach frogs have become extinct in the 1980s.
Frogs, which we know, are a collective term for members of the family Amphibians - Tailless Frogs , and exist in almost any corner of the earth near the water except the poles. Frogs can live both on land and in water. Therefore, they generally live mainly by the small river, and the small partners who live in the countryside must have had such an experience, and they can hear the frogs chirping every evening, which is very comfortable.
Frog mating is very special, has a special name, known as "hugging pair", the male frog will attract the female frog by constantly chirping, if the two sides agree, the male frog will jump on the female frog and hug the female frog tightly. After hugging, both female and male frogs begin to ovulate and sperm through the cloaca. Each ovulation is 3000-6000, and sperm egg cells are combined in water. After a week or so, the fertilized eggs hatch into small tadpoles, which can only breathe through gills and cannot come ashore at this stage. The small tadpole needs to develop for 2-3 months to metamorphose into a small frog, and the tail gradually fades. At this time, you can go ashore to live, and the little frogs can breed offspring in about 2-3 years.
But the "stomach frog" is more special, adult individuals are generally 55 mm long, are male individuals are smaller than female individuals. The hatching process of the "stomach frog" is very special, which is different from the reproductive hatching process of other frogs. They also need to be paired to ovulate normally, and some scientists have done experiments, not through the act of hugging, so that sperm and egg cells are directly combined in water, so that the survival rate of frog offspring is very low. Although there is no actual behavior, it is an indispensable process. After the "stomach frog" holds the egg and lays the egg, the sperm and egg cells are combined, and after an hour, the "stomach frog" will swallow all the fertilized eggs into the stomach and let them hatch in the stomach.
This also means that the stomach acts as a "uterus" to use, a process that takes about 7-8 weeks to complete, and finally spits out the baby frog through the mouth, which is the process of the baby frog being born in the mouth. This means that the entire metamorphosis process from the fertilized egg - small tadpole - small frog is completed in the stomach of the "mother frog", in this incubation process, it is conceivable that the stomach of the mother frog has been transformed into a temporary uterus by the function of digesting food. Almost unable to eat at the whole stage, when the female frog "pregnant", the body is gradually enlarged, and finally even the lungs are flattened unable to breathe, this time can only be exchanged through the skin for gas exchange.
A team of researchers from Michael Taylor of the University of Adelaide in Australia, after 8 years of breeding, observation and experimentation, successfully produced a documentary on the breeding process of Australian frogs. Let's understand the "childbirth" process of this Australian frog, the female frog will be opened to the maximum, the small frog is like an arrow that is shot, quickly jumping out of the mother frog's mouth, the mother frog in the documentary in a few days symbiotic 26 small frogs, these small frogs are around the "mother" for a long time, until they grow older will not leave. In fact, we can see that there are still relatively few small frogs born in this incubation method, unlike direct hatching in water, and thousands of small tadpoles can appear.
Scientists can not understand this behavior of "stomach frogs", because this way of hatching does not increase the survival rate, and even the number of offspring is greatly reduced, which is also a harm to adult female frogs, because after swallowing the eggs into the stomach, the special substances of the fertilized eggs will make the stomach no longer secrete gastric acid to create a good incubation environment, but the mother frogs cannot eat until the birth of the baby frog. Scientists can't fully understand the hatching process and principle of stomach frogs, because both species of stomach frogs are extinct.
In fact, you can imagine that their special hatching method is incomparable with most other frogs, and frogs of other species ovulate 3,000-6,000 eggs each time, and then let them hatch in the water to grow, and the number of offspring is also very large. But this special way of stomach frog, the number of breeding offspring is bound to be greatly reduced, it is conceivable that this special hatching method may be the root cause of the extinction of stomach frogs, the survival of the fittest! Unable to better adapt to the natural environment, it is sooner or later to be eliminated.
At present, scientists just want to carefully study this process and can't do it, but this special hatching method of stomach frogs is indeed very novel, opening up our horizons, and nature is all strange.
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