Research puzzle: How did bees evolve luring, then roasting a predatory hornet to death?
|April 3, 2012||Posted by News under Evolution, Animal minds, News|
In a furnace ball made of their own bodies?
In “Japanese bees cook enemy in ‘bee ball’” (Reuters/ABC News, April 3, 2012), we learn,
When confronted with their arch-enemy, the aggressive giant Asian hornet, the honeybees will attack it by swarming en masse around the hornet and forming what scientists call a “hot defensive bee ball” – a move unique to their species.
With up to 500 bees all vibrating their flight muscles at once, the bee ball cooks the hornet to death.
This vid shows that such bees make a point of not attacking; rather, they allow the predatory hornet to enter the hive, and wait till it attacks one of them before they form the ball and roast it. Then they go out and remove its scent markers from the hive.
The move is set off by bees posted as “guards” at the entrance to the colony whenever they detect an intruder. It is thought to have evolved because the bee’s stingers aren’t strong enough to penetrate the hornet’s tough exo-skeleton, researchers say.
That’s an incomplete way of understanding the problem because the fact that “the bee’s stingers aren’t strong enough to penetrate the hornet’s tough exo-skeleton” could just be tuff luck for the bees. It doesn’t explain how the behaviour evolved, only why it provides the bees with an advantage.
“When a member of the colony, a worker drone, is killed, this is a grievous loss for the hive. Evolution has reacted in this way (for their survival),” says Masato Ono, a Japanese honeybee and hornet expert who was also part of the study.
In this case, we are saying that evolution is an intelligent force that reacts to ensure the insects’ survival because the death of a worker is a grievous loss for the hive.
It may be true. It may be evolution. But it is not Darwinian evolution.
See also: Why some people think that Monarch butterflies show evidence of design