Will the body of a liger really keep growing like crazy?

People have always had a lot of controversies and misunderstandings about ligers. The controversy is nothing more than "artificial products". Many zoos are trying their best to breed ligers for commercial interests, and even Tigers, ligers and other rarer "artificial animals" make some people feel uncomfortable.

There are various misunderstandings about ligers. For example, the most widely circulated one is that the size of ligers will be uncontrollable and can continue to grow. Since most ligers in the world are larger than their parents, many people believe this to be true.

Liger

Can the liger really continue to grow like crazy? Obviously not. Compared with its parents, lions and tigers, the growth process of ligers is indeed longer, but when it reaches a certain level, it will no longer grow.

For example, Apollo, a liger in South Carolina, USA, weighed an astonishing 320 kilograms, but that was all. Apollo, who was born in 2013, passed his peak weight. As I get older, I gradually lose weight.

The secret of the huge size of the liger Apollo Liger

The offspring of a male tiger and a female lion are called ligers, and the offspring of a male lion and a female tiger are ligers Most tigers and ligers in the world are smaller than their parents, while most ligers are much larger than their parents. Some people think this is because female tigers are larger than female lions.

In fact, this is a subjective assumption made by people based on general rules and cognition. In fact, it is not the case. The factors that determine the size of ligers and tigons include acquired nutrition, growth environment, etc. , and more importantly, it is a genetic issue. DNA determines how big they can grow.

Lions are the only cats that live in groups, while tigers, like most cats, live alone. Due to different life patterns, they determine the direction in which they evolve. In the life of a male lion, the time it takes to occupy the pride of lions and have mating rights is very short. Once it passes the prime of life, it is easily defeated by other male lion alliances, so it must cherish its time.

In addition, in order to prevent her offspring from being bitten to death by other male lions, female lions sometimes mate with multiple male lions. For a male lion, he hopes that his children will surpass the children of other male lions at the starting point. Therefore, in the long process of biological evolution, male lions have gradually evolved a gene that can promote growth. Let us temporarily call it As "promoting factor".

For female lions, the running water of male lions makes the lion pride strong, so no matter which group of male lions takes over the pride, and which male lion's offspring are their own flesh and blood, so for the sake of fairness , bringing all children back to the same starting line, the female lion also evolved a gene related to inhibiting growth, tentatively called "inhibitor factor".

Under the interaction between the female lion's "inhibitory factor" and the male lion's "promoting factor", the promotion and inhibition cancel each other out, then the influence will disappear, and the lion cubs born will be our common and normal ones. Body size.

Let’s talk about tigers. A male tiger’s territory often contains 3-5 female tigers. Because tigers have a strong sense of territory, they do not allow intruders of the same gender to move inside. There is also fierce competition, but due to personality, it will take a little longer for male tigers to change dynasties. For this point, we refer to the life of the legendary tiger king Zhajir in Bandhavgarh National Park, India. Although he was 3 years old (1987) He challenged the then Tiger King Barka, but it was not until 1992 that he defeated Barka.

Both Barka and Zhajir reigned for a long time (more than 8 years), so they had enough time to reproduce. So for male tigers, the tiger cubs in the territory are basically their own offspring, so there is no need to treat them differently.

Since male tigers can confirm that they are their biological children, let alone female tigers, there is no need for it to evolve suppression-related genes.

After seeing this, I believe many people should have understood the secrets of the body shapes of tigones and ligers. As everyone thinks, tigons are the offspring of male tigers and female lions, so what? A combination of non-promoting and non-inhibiting, so the tigon will become smaller and not as big as its parents. The liger is the offspring of a male lion and a female tiger. Even if there is a combination of promotion and suppression, its size will naturally become larger, easily surpassing its parents. The male lion gene cannot make the liger grow forever

After understanding the secret of the huge size of the liger, people also have some misunderstandings. Since the liger is in the male lion? Promotion factor? The body size will become huge under the influence of "inhibitory factors", so without the control of "inhibitory factors", will the body size of ligers continue to grow indefinitely?

In fact, not. According to existing research, the larger the animal, the longer the growth process. For example, rabbits basically stop growing after 8 months of sexual maturity, while brown bears , although they have reached sexual maturity at the age of 5, they are still growing at the age of 10. The same is true for ligers. It takes longer to grow than lions and tigers, and it takes longer to grow to adult size.

It is a fact that ligers lack “inhibitory factors”, but the male lion’s “promoting factors” will not allow it to grow forever. As age increases, ligers will continue to grow, but There is also a time limit, that is, when they reach sexual maturity, their bodies stop growing. During the subsequent aging process, ligers will gradually lose weight like other animals. This is a normal phenomenon and is the majority of animals. The aging process in animals. Especially in the last few years of life, weight loss occurs more rapidly.

The main reason why ligers give people the illusion of being able to grow indefinitely is that they grow fast but the process is slow. To put it simply, their bodies grow very quickly and they take only a short time to grow. longer.

It’s easy to understand. Take us humans as an example. Some people may grow slowly and stop growing when they are seventeen or eighteen years old, so they are the favorites in the class from childhood to adulthood. Among that group of people, some people grow very fast and are still growing in their 20s, so they have been the tallest in the class since childhood. This is a normal phenomenon.

For ligers, scientists have done a study and found that it takes about 90 days for a liger to grow to 32 pounds, while it takes about 130 days for a tiger to grow to 32 pounds. In addition, the average weight of a 4-year-old lion is 450 kilograms, the average weight of a 4-year-old tiger is 540 kilograms, and the average weight of a 4-year-old liger is about 810 kilograms. Compared with the growth rate of lions and tigers, the growth rate of ligers is very high, which results in the size of ligers being much larger than that of lions and tigers during the same growth period. Do ligers exist in the wild?

We all know that ligers are artificial products, so although their numbers are small, they are not listed as endangered species for protection internationally. This is why many zoos regard them as extremely important. Preciousness is mainly driven by commercial interests. After all, lions and tigers are star species in zoos, and they, the crystallization of love, are more attractive to the public. The earliest recorded liger in the world, Lilly, was born in France in 1981. So did there exist wild ligers in history?

To clarify this issue, we must first know whether tigers and lions were distributed in the same region in history. This is a prerequisite. Modern tigers only exist in Asia. If there is an intersection, the most likely areas are West Asia, Central Asia, and the Indian subcontinent in the early years.

All modern lions in the world originated in eastern and southern Africa. About 20,000 years ago, lions in North Africa gradually spread to southern Europe, Central and Western Asia and other places, reaching as far as the Indian subcontinent. . The lions that entered Asia quickly adapted to the environment and eventually evolved into Asiatic lions.

The tiger originated in East Asia, that is, the area where the South China tiger lives. After spreading several times, the tiger spread throughout most parts of Asia, reaching eastern Anatolia in the west, and ascending to the South China Sea in the south. Many islands in Southeast Asia.

The time point when tigers spread to the Indian subcontinent was the last glacial period, about 11,500 years ago, which was similar to that of lions. Therefore, from the historical distribution of lions and tigers, and the time point, we can roughly infer that in During the Holocene, that is, starting from 11,700 years ago, lions and tigers were distributed in the same region for a long time in Central and Western Asia and the Indian subcontinent.

Historical sympatric distribution map of ligers and tigers

Since wild tigers and lions have such a large area and such a long period of sympatric distribution in nature, have they ever mated? Possible? Although there is such a probability, I think it is almost impossible in the polar regions. First of all, from the perspective of micro-habitat, tigers are solitary animals. Their favorite terrain environment is dense forests. When prey is abundant enough, they will not venture into open areas in the forest, let alone empty plains. .

Although Asia does not have grasslands as large as Africa, the activity areas of Asiatic lions are basically savannas or open areas in the forest. This type of terrain is suitable for group living, collective hunting, and when prey is abundant. , and they will not venture into the forest. Therefore, although the habitats of lions and tigers overlap greatly on a large scale, in fact their microhabitats are very different, and there are not many opportunities to meet.

In addition, when the population of a species is large, they will only mate and reproduce between species, so how can they like different species? Therefore, in the early Holocene when prey was abundant and lions and tigers were plentiful, even if ligers and ligers were distributed sympatrically, the probability of ligers appearing was minimal. However, in modern times, ligers and tigers have no possibility of sympatric distribution. It is even less likely that wild ligers will appear.