cross-posted from: https://lemmy.world/post/2712557
For the past 18 months, orcas have been attacking boats and yachts in the Mediterranean Sea near the Strait of Gibraltar. A new report of an orca boat attack in the North Sea near Scotland is a surprising development.
It's possible that the orcas are displaying “cultural evolution” and other pods are learning behaviors from one another Scientists long assumed that humans were the only animals capable of “cultural evolution”—that is, learned behaviors developed beyond the innate skills gifted to us by genetic evolution. But for a few decades now, the animal kingdom has been providing evidence to the contrary.
Monkeys and whales have shown a particular gift for cultural evolution, and other animals outside the class Mammalia have shown simpler forms of collective learning and adaptation.
Now, the majestic orca (Orcinus orca) is under scrutiny for the same kind of behavior, as boats in the Mediterranean near the Strait of Gibraltar—and surprisingly, off the coast of Scotland in the North Sea—appear to be specifically targeting boats. Although this behavior was well-known in the Iberian orca population, it’s a shocking development that orcas seemingly unaffiliated with the Mediterranean pod are exhibiting similar behaviors.
“I’d be reluctant to say it cannot be learned from [the southern population],” Conor Ryan, a scientist who’s studied orca pods off the Scottish coast, told The Guardian. “It’s possible that this ‘fad’ is leapfrogging through the various pods/communities.”
Despite being known as “killer whales,” orcas are actually members of the dolphin family and are highly sociable, using complex vocalizations to communicate with one another. The learn matrilineally, meaning “grandmother” orcas (which can live for 80 years or more) become matriarchs of their pods and pass on vital hunting skills.
With three boats sunk and upwards of 100 others damaged in Iberia, scientists think that this behavior may come from one such “grandmother” orca named White Gladis. The thought is that she may have survived a traumatic event earlier in life involving a boat, and has since taught her pod how to attack them. It’s also possible that these attacks are timed with Atlantic bluefin tuna (Thunnus thynnus) migrations, and the orcas perceive boats as competition for food.
Of course, humans are not necessarily innocent victims in these orca hit-and-runs, as boats cause noise pollution and other hazards for the creatures and other marine life. But, regardless, how exactly did an orca in the North Sea learn this seemingly isolated behavior from 2,000 miles away? Some scientists think that highly mobile pods could be capable of teaching these boat-destroying tricks to individuals in other pods.
So, will orcas always be on the hunt for boats and yachts of all shapes and sizes? Well, not necessarily. As seemingly easy as it was for the orcas to pick up this hunting trick, it’s possible that this “cultural evolution” will disappear just as rapidly. Similars shifts have happened before. For example, the website Salon reports that, a few years back, bottlenose dolphins were carrying sea sponges on their noses of the coast of Australia. But as quickly as this “fad” appeared, it became scarce, and soon disappeared entirely.
Scientists don’t know how long this particular “cultural evolution” will stick around. But considering our bang-up job protecting the planet, it almost feels like there’s a measure of justified cosmic karma at play here.