In the history of human evolution, there are actually many human subspecies, such as Neanderthals, Denisovans, etc. They used to have no strict divisions with modern races, which are equivalent to modern wolves. , In different regions have different external characteristics, but they all evolved from the North American gray wolf.
Modern technology can find sporadic DNA fragments from the tooth fossils of mammoth 1.6 million years ago. This year an American company also claimed that it wanted to spend 15 million US dollars on mammoths obtained through archeology. Elephant genes improve the genes of modern Asian elephants, hoping to obtain a special species similar to mammoths. Previously, scientists also obtained some gene fragments from Neanderthal leg bones about 400,000 years ago, and obtained information related to modern humans. A certain Neanderthal gene is still retained in the genes of modern people.
However, in the course of biological evolution, especially the emergence of sex, different sexes of the same organism have compatible reproductive systems and inherent cellular characteristics. Only the same species can mate and reproduce normally. It's called reproductive isolation. Reproductive isolation allows various species to behave independently, each in its own population or subspecies population can mate and multiply normally, and seeking a mate will not exceed the boundaries of the species. Although primitive people lack natural knowledge, their evolutionary instincts also make them do so.
There are some abnormal hybridization phenomena in the animal kingdom, which are mainly produced under the influence of humans. For example, horses and donkeys can give birth to mules. These two animals basically do not mate under natural conditions. In the human breeding environment, plus human induced horses and donkeys, they can give birth. There are also lions and tigers in a similar situation. Liger has different living territories in nature. One likes to be in the grassland and the other likes to be active in the jungle, so they can't meet them in normal times and it is difficult to mate.
The two sets of hybrids are different.Horses and donkeys have a pair of chromosomes, while lions and tigers have different numbers of chromosomes, but there are differences in chromosome structure. In these two cases, the first hybridization is actually more difficult to achieve, but donkeys and horses are animals raised in large numbers by humans. After a lot of attempts, a lot of mules have been produced, and modern humans have basically mastered it. The hybrid law of horses and donkeys can produce mules more stably.
Lions are different from tigers. The number of lions in the wild is already small, and the number of humans raised is also very small. The main purpose of raising is to restore the population, and then let them master the skills of survival in the wild in wild training Can adapt to reintroduction. There are relatively few attempts by humans to cross between lions and tigers, but so far, more than 1,000 liger beasts have been obtained, and even the second-generation hybrid offspring of liger beasts have been produced, such as liger beast Tiger and tiger liger are the hybrid offspring of liger and lion and tiger respectively.
But humans are different. In history, Soviet scientists have tried human hybrid experiments. After 1920, at the time of industrial development in the Soviet Union, a scientist in the Soviet Union tried to create a hybrid of humans and orangutans. It is expected that this hybrid animal has a stronger physique and greater strength than humans, but its intelligence is not as advanced as humans, and it does not have such a strong self-awareness as humans. Therefore, it is very suitable for training as a bearer of heavy physical or repetitive labor.
This Soviet scientist tried experiments including sperm-egg fusion, and even tried to use humans to participate in the experiment, but the final result was that no such hybrid species was developed. Therefore, the hybridization of humans with close relatives such as chimpanzees is considered Is unlikely. Later, due to the development of human ethics, such experiments were forbidden, and modern experiments with human fertilized eggs are also very cautious, requiring very strict ethical procedures, and at most, the fertilized eggs can only develop for 7-14 days. Because beyond this period, the nervous system will be produced,Early embryos may develop self-awareness.
So there is no such experiment again, but the discussion about whether humans and chimpanzees can hybridize in fact still exists today, but now no one dares to risk the world to do such an experiment. However, horses and donkeys have different chromosomes. They once shared a common evolutionary history, but in the subsequent evolution, due to the dispersion of the population, they gradually evolved into different forms, and the number of chromosomes is also different, but they can give birth to Mule.
Humans and chimpanzees have a similar evolutionary history, and the chromosomes are also coincidentally missing. What's more clever is that although humans have 23 pairs of chromosomes and chimpanzees have 24 pairs of chromosomes, the two chromosomes 2a and 2b of chimpanzees add up to the same length as human chromosome 2, and have many similar segments. In theory, humans still have the possibility of interbreeding with chimpanzees to produce offspring. It used to be unsuccessful because it was limited by the development of , ethics and other developments. There are still relatively few attempts. If large-scale attempts like horses and donkeys are possible, it will be fine. Produce hybrid individuals.
Of course, this is only possible based on biological evolution and genetic similarity. There will be no such experiments in modern times. However, in some backward African regions, the relationship between humans and animals is difficult to say, and some diseases are also spread to human populations through this method. However, this kind of phenomenon has not been mainstream, and humans can still pay attention to health problems, so in general, the chance of humans and chimpanzees producing offspring is even smaller.
However, under the blessing of modern technology, another kind of hybrid will appear. In fact, it is not appropriate to say that it is a hybrid. Instead, biological technology is used to fuse the cells of two different animals. Together, they develop into a complete individual, which is equivalent to creating a chimera. The chimera is caused by the fusion phenomenon that occurs during the embryonic development of two . The body tissues have different cell types.For example, after giving birth to a child, it is discovered that the child is a brother, but he does not have a brother. This means that his reproductive organs developed from a chimera.
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