The picture above is a pair of black langur mother and son, if not to say that many people will think of the baby monkey as a golden snub-nosed monkey, after all, the hair color difference between the mother and son is too great, and the untamed head shape of the mother monkey is also completely different from the little monkey's "big back".
So why does a black langur, which is almost covered in black hair, give birth to a baby monkey with golden hair? What about the fact that there are no similar animals in nature? Let's find out together.
Black langur, a national first-class protected animal
Almost most wild animals on the mainland are protected animals, but there are only 234 species of protected animals at the national level, and the black langur is one of them.
Black langur is a primate of the family Monkey family Langur, they mainly inhabit tropical and subtropical broad-leaved forests, from the appearance, adult black langurs are almost all black long hair, only the hair on the cheeks is gray-white, their average body length is about 55 cm, the head is relatively small, the tail and limbs are more slender.
Like other monkeys, black langurs are also a highly social animal, each monkey group is composed of an average of 6 members, larger groups up to more than 20 members, they are highly arboreal, whether it is daily life, food collection is carried out in trees, rarely go down trees.
Black langurs are diurnal animals, they are active in the morning and afternoon, and have a longer lunch break at noon, but at night they do not like to sleep in trees, but will climb into some natural caves to rest. In terms of diet, black langurs are plant-eating monkeys, they can collect more than 20 kinds of plants, and they will eat not only young leaves, shoots and fruits, but also flowers, stems and seeds.
There are two main reasons why black langurs can become national first-class protected animals:
First, their distribution is limited, in the world, black langurs are only distributed in the mainland and Vietnam, of which only parts of Chongqing, Guangxi, Guizhou, Yunnan and other provinces are distributed in the mainland;
Second, they are scarce in number. The former distribution of black langurs was not only in the three provinces above, they were once widely distributed in southern China, but with the continuous deforestation of tropical and subtropical forests, their numbers continued to decline. At the same time, because the black langur has a certain ornamental nature, it has also been hunted in the wild in large quantities.
At present, there are about 1800-2000 black langurs in the world, of which about 1700 on the mainland, this number has reached the endangered level, so the distribution limit and scarcity of black langurs are the main reasons why it has become a national first-class protected animal.
However, the good news is that with the protection and restoration of black langur habitat and the implementation of measures such as artificial breeding of black langurs in the wild, the decline of black langur population has not only been curbed, but their population in some protected areas has shown a steady growth trend.
"Black Monkey" gives birth to "Golden Monkey"?
The origin of the name of the black langur is partly because it mainly feeds on leaves, on the other hand, it is almost black all over, but the black langur can give birth to a golden monkey baby monkey with a beautiful appearance, which is really surprising, so what is the reason for this?
First of all, the newborn black langur is not golden yellow, its back and tail are actually gray-brown, other parts are golden yellow, and this color will gradually turn black after 30 days after birth. When blackening, the first part that becomes pure black is the tail, which then spreads from the tail to the hips, hind limbs, and back until it becomes completely black.
Secondly, the difference between black langur cubs and adult colors is mainly determined by the genes that control hair, and at birth, black langur cubs control the yellow gene in the hair gene is more active, and as it grows up, it is replaced by increasingly active black genes.
If another genetic mutation occurs, such as active white genes, then black langurs will also have an albino individual with white hair all over the body, but this is relatively rare, because the genes with the most active hair color of black langurs are yellow and black.
Albino black langur
The mechanism behind this color change of black langurs, scientists have given a research result, that is, to avoid or reduce the killing of adult males of the same kind. In nature, the act of killing young individuals by adult individuals is called "infanticide", and infanticide is seen in many animals in nature, especially primates.
A foreign research team after analyzing data such as infant and adult skin hair of 267 species of primates, found that animal cubs with different skin or hair colors were killed less by adult males, and black langurs are a primate that survives together with multiple females, in order to compete for mating rights, the replacement of male monkeys is more frequent, with an average outbreak of 2-3 years.
When the monkey king replacement is over, it will kill the cubs in the group like other primates and lions to stimulate the female into estrus, and the black langur cubs with bright hair are not soft for the male monkeys, but will stimulate the female monkeys to take better care of them, thereby shortening their growth cycle, and by the time the monkey king changes, they usually have grown, in this way, the black langur cubs avoid infanticide after the replacement of the monkey king as much as possible.
Therefore, the different hairs of black langur cubs are actually caused by survival evolution, simply put, only the individuals whose cubs evolved golden hair successfully survived, and this gene was passed down from generation to generation, of course, the reason for the survival of these individuals is because they have received better care (almost all close care), thereby shortening the fragile juvenile period and avoiding infanticide as much as possible.
Animals in nature that differ greatly between juvenile and adult years
In addition to black langurs, there are many animals with very different colors between adults and juveniles, such as chickens, ducks and other birds, which are either hairless or yellow at birth, which are very different from adult individuals.
In addition to birds, there are not many mammals with large differences in juvenile and adult bodies, and let's look at one of the most obvious examples - cheetahs. Cheetahs and leopards have some similar appearance, they are yellow hair with black spots, so many people will confuse the two, but in fact, although the appearance is similar, cheetahs and leopards are still very different, first of all, the cheetah body is slender, the leopard body is relatively thick, and secondly, the cheetah has two black "tear marks" on its face, and the leopard does not.
The leopard bites the cheetah
Well, let's get back to business, most cats are born with similar characteristics to adult individuals except for size, but cheetahs are different, cheetahs cubs look very different from their mothers, but are somewhat similar to a fierce small animal in the African savannah, the "flat-headed brother" honey badger.
From the picture above, we can see that the baby cheetah has silver-gray back hair that adult individuals do not have, which is the same as the characteristics of the honey badger's back, which is actually evolved for survival. Cheetahs are solitary animals, although they are fast, but their combat effectiveness is insufficient, and under the eyes of spotted hyenas, leopards, lions, African wild dogs and other animals, the mortality rate of cheetah cubs is very high.
However, scientists have found that cheetah cubs with similar characteristics to honey badgers can greatly improve the survival rate when faced with predators, because honey badgers are small, but with the spirit of not afraid of death, flexible body, sharp claws and teeth, so that lions, leopards and other animals also have headaches.
Write at the end
The difference in hair color between black langur cubs and adult individuals is actually a mechanism for hair color change that they evolved in response to infanticide, with this bright hair, black langur cubs can grow faster and receive more care, thereby avoiding adult male infanticide.
The same is true of cheetah cubs similar to the honey badger's back hair, which can avoid hunting from other predators as much as possible.
#国家一级保护动物, black langur, why was it conspicuous golden yellow when I was a child? #