According to the International Union for the Conservation of Nature, these are animals that no longer exist on Earth. The list includes 41 birds and 13 mammals.
Najín and Fatu are the only two [female] northern white rhinoceroses living on the planet after the death of [male] Sudan at the Ol Pejeta conservation center in Kenya.
After the death, the hope of preserving the species is put in the work that scientists can do in the laboratory. The center conserves sperm of Sudan and of other males of the species, and the eggs of Najin and Fatu, infertile now.
The idea of the researchers is to perform an in vitro fertilization and then fertilize the embryo in a southern white rhinoceros female.
But the probability of this working, according to experts, is quite remote, so the species seems doomed to extinction.
Its destination would be the same as that of 69 other species declared extinct in 2017, according to a report by the International Union for the Conservation of Nature (IUCN) sent to La Tercera and which considered the evaluation of 80 thousand species of the whole planet.
The document shows that among the disappeared species there are 41 birds, 13 mammals, seven reptiles and four mollusks. Among the animals, the giant Floreana turtle, the oceanic parrot, the Christmas Island bat and the Japanese sea lion stand out.
“The data regarding the sighting of a particular species come from an extensive network of researchers who determine the conservation status of an animal. In many cases, knowing it is hard to find species, it is a challenge to know when a particular species became extinct. Sometimes it is believed that it is the last of its kind, but in reality it is not. When they reappear they are called Lazarus”, explain from the IUCN about the criteria for this organization, which develops the so-called Red List of Species and [officially] declares a species as extinct.
Ezequiel Hidalgo, director of Conservation and Research at Buin Zoo [Chile], part of one of the IUCN research committees, explains how species are classified. “There are different groups of specialists and each one is in charge of updating a file. These are based on threats, distribution of specimens and population status, among others. One projects how the species will be maintained in a given period. When you come to the conclusion that there is a low number, the distribution is very restricted and has threats, they are candidates to be in one of the four threat categories that are vulnerable, endangered, critically endangered and extinct in the wild”, Explains the specialist. When does it go to extinction? “When after a period of study, animals are no longer seen, neither in the wild nor in captivity. There must be none alive on the face of the Earth. To arrive at that, the presence of the species is considered, with cameras, fingerprints and even feces. Although it is known that the last recorded species dies, it must spend a considerable time to officially declare it extinct. They have to do more studies.”
The Conservation Director of the Buin Zoo, says that while there are no unique factors to prevent an animal from becoming extinct, it says that avoiding the destruction of the habitat is the most important. “Once destroyed, the animal can be kept in captivity and automatically considered extinct in wildlife. Avoiding the destruction of the habitat would be a way to avoid the extinction of certain animals, but it is complex, because there is a sociocultural issue linked to the construction and development of commercial, agricultural or housing projects. And that development is directly related to human growth, “explains the expert.
In addition, he points out that pollution, which is everyone’s responsibility, is also an important factor. “Animals become extinct due to human causes and natural factors, such as natural disasters. To a species with a very restricted ecosystem, for example next to a volcano, if it erupts, the lava devastates and the species dies out.”
In the IUCN, they point out that the classification of species requires a process. “There is often a lapse of time between the first species recorded as extinct by a scientist and when an official assessment was made on the Red List. The process of classifying a species as extinct is rigorous because marking something as extinct can have significant implications for the protection of the species.”
Hidalgo states that in Chile there are critically endangered species, “such as the fox of Darwin, the huemul, the hummingbird of Arica and Juan Fernández, and the Andean cat. They are categorized with a high degree of threat with very low populations, which can lead to extinction.”
