Mammals in nature generally reproduce their offspring through mating between male and female individuals, which is a genetic mechanism formed by long-term evolution. This mechanism can ensure the genetic diversity of offspring, so that offspring individuals have a greater chance of survival.
<h1 class="pgc-h-arrow-right" data-track="16" > two female sharks live together for 10 years to give birth to their offspring</h1>
In fact, some species in nature that were originally mated and bred by male and female can also reproduce in solitary females when the population is very small. Sharks, for example, have recently seen incidents in which female sharks have produced offspring without mating.
The Aquarium of Caraguno, Italy, has fed two female grey star sharks, which have been kept together for 10 years, during which no male grey star shark has been introduced. However, a gray star shark has given birth to offspring, and it seems that the increase in the number of gray star sharks is a good thing, but the aquarium staff is not happy.
There have also been many incidents of female sharks breeding offspring without mating, and scientists have studied and found that the DNA of juvenile sharks matches the DNA of female sharks, and there is no genetic material of male sharks. Combined with the dilemmas faced by sharks as creatures, scientists believe that this phenomenon may mean that sharks are on the verge of extinction.
<h1 class="pgc-h-arrow-right" data-track="28" > shark parthenogenesis means that it is on the verge of extinction</h1>
The phenomenon of the mother shark reproducing offspring alone is called parthenogenesis, the shark is originally a sexually reproducing organism, and the female shark will not reproduce its offspring alone unless there are special circumstances. The offspring thus reproduced have highly similar genetic material and are difficult to cope with certain genetic diseases. Population extinctions are also susceptible to some larger environmental changes.
Sharks have this rare reproductive phenomenon because of the sharp decline in their populations. With the killing of sharks by humans, the number of sharks is getting smaller and smaller, and the flesh of rat sharks and white-spotted horn sharks is delicious and sought after by European consumers, and these sharks are naturally hunted by many people because they have a large enough market demand. Asian consumers are seeking to eat shark fins, and those shark species with larger fins are therefore hunted.
There may also be some sharks that have survived because there is no such market demand. But many shark species have a large market demand, and their populations are decreasing with over-hunting. After these sharks were reduced, other shark species that were originally unpopular became substitutes and were hunted, and the final result was the extinction of all shark species.
<h1 class="pgc-h-arrow-right" data-track="29" > way to avoid shark extinction</h1>
Shark parthenogenesis is an emergency measure initiated by sharks, and although it can alleviate the scarcity of populations, it does not really solve the problem of insufficient populations.
The number of offspring produced by parthenogenesis is significantly lower than the number of offspring produced by sexual reproduction. And because there is no differential combination of genetic material, it is more difficult for the offspring to survive. In this way, the more the phenomenon of unisexual reproduction of sharks occurs, the smaller the population of sharks, which is an indicator of changes in the number of shark populations.
From another perspective, sharks face different problems than other endangered species. Other endangered species are more easily protected, and by establishing protected areas, the number of endangered species can be controlled within a reasonable range without such extreme conditions. Sharks have a wide range of activities, and it is difficult to completely ban the killing of sharks.
Perhaps a better way to avoid shark extinction is to stock the sharks by artificial breeding. Although sharks do not seem to have any connection with humans, even if they go extinct, they will only affect marine ecosystems. But subtle effects are difficult to reflect in the short term, and if sharks are really extinct, they will have a great impact on some aspects of humanity in the long run.
As the highest predator in the ocean, without sharks, many fish will multiply in large numbers and marine ecosystems may collapse. Market demand is the direct cause of shark hunting, to avoid shark extinction, or to form a conscious consumption habits.