Against poaching, did elephants invent genetic defense?
More and more elephants would be born without their tusks today in Africa. According to some researchers, this is a genetic evolution intended to protect the species against poaching of which it is a victim because of the value of ivory.
Observations show that more and more elephants no longer have tusks or have extremely short incisors. "In Addo National Park in South Africa, this would concern up to 98% of the 174 specimens present," reports Sciences et Avenir. An increase in the number of defenseless females has also been observed in Zambia, Tanzania and Uganda in recent years.
This situation had already been observed on pachyderms in Gorongoza National Park, Mozambique. During the civil war (1976-1992) which raged in this country, these animals were particularly hunted for their ivory in order to finance the purchase of weapons. This gave defenseless elephants a biological advantage. Result: "Recent figures suggest that about a third of young females (those born after the end of the war in 1992) have never developed tusks. However, this absence normally occurs in only 2 to 4%. African elephants, "National Geographic reported in November 2018.
UCLA researchers attempt to understand tusklessness among Mozambique elephants https://t.co/iXORSDWyaX pic.twitter.com/TPRJHGvrQg
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Man would therefore indirectly have a role in the evolution (biologists prefer to speak of "genetic drift" rather than "evolution") of elephants. The absence of tusks being genetic, "the offspring (male or female) would have naturally inherited this characteristic, ie 33% of elephants aged between 10 and 20 years. Thus, poaching would have had an impact on the increase in the number of pachyderms. with atrophied incisors, "says Siences et Avenir.
The phenomenon is not specific, it seems, to Africa since it is also described in China. "The gene responsible for the lack of tusks is spreading among elephant populations living in Yunnan province, in the southwest of the country. This gene, generally present in 2% to 5% of elephants Asians, has been recently discovered in 5% to 10% of Chinese elephants, ”noted the Beijing China Daily in 2005.
For zoology professor Zhang Li, "the longer their tusks, the more they run the risk of being shot by poachers." “Those who do not have a better chance of surviving, hence the spread of the gene for lack of defenses in the species. This is not a natural evolution, but a change induced by force of arms ”, concludes the zoologist to explain this evolution.
It must be said that the price of ivory is enough to arouse the appetite of poachers: "A 50-year-old male can have tusks weighing up to 49 kilos each. With a world price of ivory of around at $ 1000 per kilo, that's a salary of nearly $ 100 for poachers, "notes the New York Times.
A rather atypical example of artificially induced natural selection.
The hunt for ivory targeting the pachyderms endowed with the largest tusks quickly had the effect of selecting individuals without tusks or endowed with very short tusks. The phenomenon was fairly rapid in Uganda. in half in just 35 years!
Will the elephant of the future be devoid of this attribute?
