Since 1970, the animal populations have declined on average 60%. This is devastating as a decline in a species' population could have a tremendous impact on the ecosystem. For example, a decline in bee populations could mean less pollination, which would have a direct impact on crops and the population of other animals. Even with other animals, their extinction or change in population could severely impact the ecosystem. However, groundbreaking discoveries in biotechnology could have the ability to save many animals from extinction, and possibly bring back animals from extinction.
This graphic describes the cloning process! Image Source
The process of cloning animals starts by removing a somatic cell, such as a skin cell, from the animal that they are cloning. Then, the DNA is transferred into an egg cell with a removed nucleus using a method called Somatic Nuclear Cell Transfer (SCNT) with different techniques, including electric currents or injections. The method of electric currents fuse the somatic cell to the egg, while the method of injection uses a needle to inject the nucleus of the somatic cell into the empty egg. As this is reproductive cloning, egg is grown into an early-stage embryo in a test tube, and transplanted into a surrogate female animal. When the female animal gives birth, the baby animal will have the same genetic makeup as the original animal. However, some factors are environmental, so the animal may not look exactly alike.
This was Dolly the sheep! Image Source
Within the last half century, many animals have been cloned, including some endangered animals. One of the most famous includes Dolly the sheep, who was cloned by Scottish researchers in 1996. This was the first mammal that was cloned from a mature somatic cell. Dolly was cloned from a 6 year old sheep, and Dolly died in 2003 when she was 6 years old. However, sheep usually live up to 12 years. Why did she die much earlier than other sheep? A reason for this is because we have a nucleotide sequences called telomeres that are on the end of our chromosomes. Telomeres protect chromosomes from damage and deterioration, but with each new divide from cell division, the telomeres shorten. Eventually the telomeres will shorten to the point that the cell dies. When you clone an animal using mature somatic cells, the clone may receive telemeres that have already been shortened, causing a decreased lifespan. Cloning can also lead to defects such as to the heart, liver, and brain, and other health effects leading to premature death. This was shown in Dolly, since she only lived half of a sheep's lifespan. In addition, endangered animals such as the gaur, have been cloned to research conservation cloning. They used cryopreserved gaur skin cells and transferred the DNA into domestic cow embryos, then implanted the embryos into a domestic cow. On January 8, 2001, a baby gaur was born but sadly died two days later due to dysentery. However, this research allowed for valuable insight into the possibility of conservation cloning. Another cloned animal was the cloned tabby cat named CC, short for Carbon Copy, who was cloned in 2001. While CC was a brown and white tabby cat, her somatic cell donor, named Rainbow, was a calico cat. This is because the inactivation of X-chromosomes that influence coat colors in cats occur randomly, so not all clones look alike. The cloning of Rainbow and CC led to pet cloning, as it allows pet owners to reunite with a copy of their beloved pet.
However, while animal cloning has been proven to be successful, there are ethical, evolutionary, and health issues associated with conservation cloning. To illustrate, in Darwin's Theory of Evolution, it states that natural selection occurs because a variation in the population allows for an organism to change over time. By cloning endangered species, many of the animals will have the same genetic makeup, which will cause a loss of genetic variation that is crucial for evolution and survival. As stated above, cloning can also lead to defects and diseases, which is troublesome for the long-term survival of a species. Cloning of endangered species has also been highly inefficient, because a lack of understanding of animals' reproductive systems leads to hundreds of failed clone attempts. In fact, it took 244 attempts to clone Dolly, and while technology has gotten better since then, cloning endangered animals has many challenges associated with it. Additionally, many worry about the effects of cloning on conservation efforts. Since we may be able to bring animals back from the dead, conservation of land, reverting climate change, and other issues that were the root cause of animal populations declining in the first place may be put on hold because of this modern technology. The survival of a species can't always rely on technology, and it is important to consider the consequences of biotechnology. Biotechnology has many helpful uses, including in environmental science, so our solution to animal conservation should help the prolonged and self-sustaining survival of a species instead of relying on human technology.
To conclude, biotechnology in animal conservation has great potential, but not by cloning. While cloning may be useful in saving critically endangered species, there are many risks associated with cloning, especially in a population. We should use biotechnology to create new and innovative solutions that solve problems from the root cause, instead of cloning each animal as the population diminishes from overhunting, habitat loss, and more. Animals are critical for the survival of the ecosystem, so we must do our part in protecting and preserving our environment. With new understandings however, cloning may play a valuable role in the future of wildlife conservation.
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