How Dreaded Ivory Poaching Led to Evolution of Modern Tuskless Elephants

Researchers have discovered that decades of ivory hunting have resulted in tuskless elephants' development, demonstrating that people are "actually altering the anatomy" of wild creatures.

According to research published in the journal Science, a previously unusual genetic mutation causing tusklessness had become quite widespread in some populations of African elephants following a period when many were murdered for their tusks.

Researchers investigated why female elephants in Mozambique's Gorongosa national park were commonly born without tusks and discovered that the animals had been genetically modified due to ivory poaching.

Increased Poaching

During the Mozambican civil war, when military forces on both sides murdered 90 percent of the elephant population to create ivory sold to fund the fight, elephants with tusks were highly likely to be hunted. Those lacking tusks were left alone, which enhanced their breeding chances and gave their progeny the tuskless characteristic.

The repercussions of this are still apparent in around 700 elephants that reside in the national park a few generations later. The study's lead author, Robert Pringle of Princeton University's ecology and evolutionary biology department, claimed it demonstrated the influence of human involvement in nature.

"What I think this study demonstrates is that it's more than statistics," he added. People have such an influence that we are physically changing the structure of animals."

An Elephant Anomaly

According to Pringle, the Gorongosa national park has long piqued the curiosity of academics, who thought the previous poaching was to blame for the anomaly, although the specific mechanics of the problem were unclear.

"One of the noticeable aspects is that many female elephants lack tusks, and we were interested in this occurrence," he added. We realized that, although there had been a lot published about elephants becoming tuskless at times, especially in areas where there had been much poaching, nobody knew why. And no one had measured or recorded the phenomena, allowing them to link it to a reason rather than merely guessing about its causes."

A Genetic Phenomena

The researchers thought the phenomena had a genetic origin, and the fact that it was only seen in females showed it had something to do with sex. In addition, the researchers discovered a genetic difference between tusked and tuskless elephants after analyzing their genomes.

Researchers discovered two potential genes on the X chromosome, one of which is known to have a role in mammalian tooth formation. These genes are connected to an X-linked dominant condition in humans that causes lateral incisor development to be stunted.

Genetic Adaptation

Female elephants are protected from poaching by the probable mutation of one or more genes, while male elephants are killed because they do not grow correctly in the womb.

Tuskless Elephants

About half of male elephant calves born to a tuskless mother will have this genetic defect, meaning heavily poached elephant populations may be severely reduced in males. However, according to Pringle, this problem is reversible over time because populations have been rising for two decades and have more than quadrupled since they were on the verge of extinction in the 1990s.

"As a result, we expect this condition to become less common in our study group," he added, "given that the conservation picture remains as favorable as it has been previously." "There is a deluge of dismal news about biodiversity and people in the ecosystem, and I believe it is critical to emphasize that there are some bright spots in that picture."