Elephants born without tusks in ‘evolutionary response’ to poachers (2021)

Elephants are evolving to be tuskless after decades of rampant poaching in Africa, researchers have discovered.

The rare tuskless genetic condition in Gorongosa National Park in central Mozambique has become far more common after years of ivory hunters devastating the species.

Around 90 per cent of the country’s elephant population were slaughtered between 1977 to 1992 by Kalashnikov-wielding armed groups for ivory to fund a bloody Cold War-era conflict.

The survivors were likely to share a key characteristic: half the females were naturally tuskless – they simply never developed tusks – while before the war, less than a fifth lacked tusks.

Like eye color in humans, genes are responsible for whether elephants inherit tusks from their parents. Although tusklessness was once rare in African savannah elephants, it's become more common – like a rare eye color becoming widespread.

After the war, those tuskless surviving females passed on their genes with expected, as well as surprising, results. About half their daughters were tuskless. More perplexing, two-thirds of their offspring were female.

The findings were described as a “bright spot” in a storm of negative news about biodiversity by lead researcher Robert Pringle, at Princeton University.

However, it is not all good news. The trait is only seen in female elephants and researchers said that genetic sequencing shows that the trait is linked to a mutation in the X chromosome, which can be fatal to male elephants in the womb.

from Hacker News https://ift.tt/aHMzWec