Let’s take a look at what these elephants are missing. Such "evolution" is heartbreaking.
A new report published by Science magazine on October 21 shows that African elephants have undergone an amazing evolution. A large number of female elephants are born without ivory, and this evolution is actually caused by the slaughter of ivory by humans. .
Researchers found that at least 50% of female elephants in Gorongosa National Park in Mozambique have no ivory.
These female elephants seem to have survived due to rapid evolution, but in fact they are only temporary living. It affects not only the female elephants, but also the death of the male elephants, and even the survival crisis of the entire elephant herd.
During the Mozambique Civil War from 1977 to 1992, both sides killed 90% of the local elephants for precious ivory.
The result of this slaughter is that a large number of female elephants are now born without ivory, because these are the female offspring of female elephants who survived the war because they did not have ivory.
Mathematical models show that such changes are almost certainly the result of natural selection, not accidental.
During the Civil War, those female elephants without ivory had more than five times the chance of survival.
Princeton University evolutionary biologist Dr. Shane Campbell-Stanton and his team studied long-term data and found that before the war, at least 20% of female elephants had no ivory. This reflects the earlier pressure of poaching. In the well-protected elephant herd, only 2% of elephants do not have tusks.
The intuition of the scientists came to the confirmation of the results of the genetic study of the elephant family without ivory.
As expected by Dr. Stanton's team, a gene called AMELX carried on the X chromosome of the female elephant is the key.
Absence of ivory is a predominant genetic trait, carried by females.
Half of the female cubs of a female elephant without the ivory gene have ivory and the other half have ivory; while half of the male offspring of this female elephant have ivory, the other half may die before birth due to genetic defects and incomplete development.
Dr. Stanton pointed out that this genetic mutation is killing male elephants: part of them will die due to birth defects, and the other part will be more concentrated hunting targets due to scarce ivory after birth.
Although evolving into elephants without ivory allows them to temporarily escape the killing of poachers, this has serious long-term consequences for elephants.
Elephants usually use their tusks to break trunks in search of food, or dig pits for water, and also for defense.
"When you don't have this critical tool, how do you debug your behavior and compensate for this missing part?" Dr. Stanton pointed out that scientists now want to figure out how elephants without ivory live.
He also pointed out that with the increase in elephants without ivory, this will not only affect the lives of these elephants, but also the survival of the entire elephant herd, because the number of new male elephants will become less and less.
Normally, both male and female African elephants have tusks.
However, some elephants now have no ivory.
While serious poaching continues to exist, those elephants with ivory will continue to be slaughtered, while elephants without ivory are more likely to survive and pass on their genes from generation to generation.
Fani Peltier, a population biologist at the University of Sherbrooke in Canada, said that the fact is that species must pay for this rapid evolution. "Natural selection always has a price, and this price is life."
Chengdu Commercial Daily-Red Star News Reporter Lin RongKeywords: