However, some primitive animals in nature, even vertebrates, have parthenogenesis, such as Daphnia, Komodo monitor lizard, narrow-headed hammerhead shark and small fire ant. It should be noted that parthenogenesis does not mean that hermaphroditic individuals breed offspring, but that real male or female individuals can directly produce offspring.
Take the narrow-headed hammerhead shark as an example. Female sharks can combine polar bodies and egg cells produced in their bodies into fertilized eggs. Polar bodies are also formed during meiosis to produce oocytes. The polar bodies of most female animals will die soon, and only a few can 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. After that, 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 their offspring 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, there are some genetic mutations in their bodies, and they will not live for two days. It is difficult to experiment on gay and lesbian reproduction.
Judging from animal experiments, homosexual reproduction is feasible. So, is this feasible for humans?
In this regard, Australian biologist David? David molloy expressed optimism. He believes that genetic technology can enable infertile heterosexual couples to have children, and even allow two women to 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 and 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.