Apr 7, 2016

Insect Panama Papers? Corruption Exists Among Animals, Too

Humans are a cooperative species by nature, but no doubt there are many individuals who prioritize their own interests to the detriment of the greater good. Look no further than the recent news around the “Panama Papers,” a 2.6-terabyte data leak from the law firm Mossack Fonseca documenting how companies, political leaders, wealthy individuals and even criminals hide their assets.

Corruption isn’t exclusively a human vice, though; animals do it, too. Even eusocial species — highly organized, cooperative animals that share in the responsibility of raising offspring and have a clear division of labor — will cheat each other when given the opportunity.

Take ants, for example. A model of cooperation in the animal kingdom, ants cluster into highly organized colonies, with labor divided among workers, soldiers, drones and a queen. A 2008 study on leaf-cutter ants published in the Proceedings of the National Academy of Sciences, however, found the ant world rampant with cheating and corruption.

How exactly does an ant cheat the system to get ahead? While researchers had believed that all larvae had the opportunity to develop into queens so long as they were fed certain foods, DNA fingerprinting found that the offspring of some ant fathers were more likely to become queens than others, according to biologist Bill Hughes, then of the University of Leeds. These ants possess a “royal” gene that gives them an advantage over other ants, cheating the others out of a chance to become queens.

These royal genes are exceedingly rare within an ant colony, “an evolutionary strategy by the cheaters to escape suppression by the altruistic masses they exploit,” Hughes said.

Bees aren’t much better. Like ants, bees exist in stratified societies, separated across workers, drones and a queen. Offspring within a colony are produced entirely by the queen, a kinship meant to hold together bees’ social structure — or at least that’s how it’s supposed to work.

According to a 2009 study published in Molecular Ecology, worker bees within the species Melipona scutellaris, a stingless Brazilian bee, will reproduce behind the queen’s back. The study, which examined the lineage of 600 males across 45 colonies, found that nearly a quarter of the bees were sons of workers rather than the queen. Rather than cooperating, the workers were instead in conflict with their queen.

Reproduction isn’t really about passing genes on to the next generation in this case. Instead, worker bees that are reproducing live almost three times longer than those that don’t, nearly matching the life expectancy of the queen. The reason why is that reproducing worker bees usually do a lot less work and avoid potentially dangerous tasks like foraging. The individual benefits for reproductive worker bees come at a cost for the entire colony, of course. The more worker bees there are reproducing, the lower the collective production of the colony and the worse off everyone is.

This reproductive tug-of-war between workers and queens isn’t unique to Melipona scutellaris. A 2013 study on honeybees (Apis mellifera) found evidence of a similar conflict.

Read more at Discovery News

No comments:

Post a Comment