However, some primitive animals in nature, even vertebrates, are parthenogenetic, such as Daphnia, Komodo monitor lizard, narrow-headed hammerhead shark, small fire ant and so on. It should be noted that parthenogenesis does not mean that hermaphroditic individuals reproduce offspring, but that real male or female individuals can directly produce offspring.
Take the narrow-headed hammerhead shark as an example, the female shark can combine the polar body with the egg cells produced in the body to form fertilized eggs. Polar bodies are also formed in the process of producing oocytes through meiosis. Most female animals will die soon, and only a few will survive.
On the other hand, scientists can also make bisexual animals parthenogenetic. The existence of parthenogenesis means that homosexual reproduction is possible, and males and other males or females and other females can produce offspring. In fact, animal cloning can be regarded as homosexual reproduction.
1996, British scientists extracted the nucleus from a ewe and transplanted it into the egg cells of another enucleated ewe. Stimulated by electric current, egg cells begin to divide and then develop into embryos. Then the embryo was transplanted into the third ewe for further development, and finally the first cloned sheep was born? Dolly. When this cloned sheep grows up, it can reproduce normally with the ram.
In 2006, Japanese biologist shinya yamanaka discovered induced pluripotent stem cells (iPS), which can be transformed into various cells, including germ cells in theory. Through this technology, scientists successfully induced the development of mouse germ cells.
From 2065438 to 2008, biologists of China Academy of Sciences modified the imprinted genes of mice (which can only express genes from one parent) by gene editing technology, and finally successfully produced offspring by combining the egg cells of one female mouse with the embryonic stem cells of another female mouse. Offspring mice can grow up healthily, and they can also reproduce through bisexual reproduction.
On the other hand, scientists also conducted homosexual reproduction experiments between male mice and male mice. Although they have successfully bred offspring, they have some genetic mutations, and they will not live for two days. It is very difficult to carry out gay and lesbian reproductive experiments.
Judging from animal experiments, homosexual reproduction is feasible. So, is it feasible for humans?
In this regard, Australian biologist David? David molloy expressed optimism. He believes that genetic technology can make infertile heterosexual couples have children, and even two women have children. Dr molloy estimates that in the next 20 years, women will be able to have children without men.
However, there are great ethical and moral challenges in human homosexual reproduction. It's hard to imagine what their outlook on life would be like if human beings whose parents were both male or female were really created. At present, the experiment of cloning human embryos needs to be carried out in vitro, which strictly limits further human experiments.