New research discovers worker bees in 'reproductive class war' with queen

September 9, 2009

Bee colonies are well known for high levels of cooperation, but new research published in Molecular Ecology demonstrates a conflict for reproduction between worker bees and their Queens, leading some workers to selfishly exploit the colony for their own needs.

The study focused on Melipona scutellaris a Brazilian species of highly social stingless bees, found throughout the Atlantic rainforest. Colonies contain around 1,500 workers and are headed by one single-mated Queen.

Denise Alves, Dr Tom Wenseleers, and their co-authors carried out a genetic study of nearly 600 males from 45 colonies to discover the parentage of the worker population. Their results showed that 22.89% of Melipona scutellaris males are sons of the workers rather than the Queen, demonstrating an on-going conflict for reproduction.

"Surprisingly our results show that over 80% of the worker's sons had genotypes that were incompatible with them being the sons of the present queen," said Alves. "This demonstrates, for the first time, how workers continue this conflict by reproductively parasitizing the next-generation of the workforce for their own selfish benefit."

Worker bees are generally unable to mate, but are capable of laying unfertilized eggs which can develop into male . To assure dominance over reproduction the Queen often selectively eats any worker laid eggs. In some species other workers may eat the eggs of fellow workers in what is known as 'worker policing'.

Even with these barriers there is much to gain for worker bees producing their own offspring, however the benefit is entirely for the individual and can be costly for the colony overall. The team found that workers who reproduce can live as much as three times longer, meaning that reproducing workers have a life expectancy almost matching the Queen herself.

This added is thought to be because workers who reproduce do not usually carry out risky tasks such as foraging. However as worker bees who are reproducing are not working, an increase in individual workers who reproduce puts the collective production of the colony in jeopardy, hence a queen-worker conflict over the production of males ensues.

To demonstrate this conflict the team studied the genotypes of worker and queen bees from 45 colonies. If a male carried a not present in either the mother queen or her mate, then it was clear the male was either the son of an invading bee or of a worker who superseded the Queen.

The team found that of 576 males genotyped, 61 (10.59%) could not be assigned to the Queen and were therefore definitely worker's sons. Of these 61, 14 (22.95%) were consistent with being sons of workers of the current queen while 47 (77.05%) were derived from workers derived from a previous, superseded queen .

The team estimates 77.11% of the males were the queen's sons. 4.34% were the sons of the workers derived from the current queen and 18.54% were the sons of workers derived from a previous, superseded queen.

"These results are the first explicit demonstration that conflict over male parentage in insect societies is not just played out between the and workers," concludes Alves, "but shows that the conflict may also spill over from one generation of workers to the other."

More information: Alves.DA, Imperatriz-Fonseca.VL, Francoy.TM, Santos-Filho.PS, Billen.J, Wenseleers.T, ‘The Queen is dead - long live the workers: intraspecific parasitism by workers in the stingless bee Melipona scutellaris’, Molecular Ecology, 2009: DOI: 10.1111/j.1365-294X.2009.04323.x

Source: Wiley (news : web)

Explore further: Why do some queen bees eat their worker bee's eggs?

Related Stories

Why do some queen bees eat their worker bee's eggs?

December 4, 2006

Worker bees, wasps, and ants are often considered neuter. But in many species they are females with ovaries, who although unable to mate, can lay unfertilized eggs which turn into males if reared. For some species, such as ...

Wood ant queen has no egg-laying monopoly

June 28, 2007

The reproductive monopoly of the ant queen is not as strong as is often thought. Dr. Heikki Helanterä and Prof. Lotta Sundström, biologists working at the University of Helsinki, Finland, investigated worker ovary development ...

Scientists study insect 'egg police'

November 8, 2006

British and Belgian scientists say social sanctions, not voluntary altruism, stop workers in insect societies from reproducing.

Researchers at Illinois explore queen bee longevity

May 8, 2007

The queen honey bee is genetically identical to the workers in her hive, but she lives 10 times longer and – unlike her sterile sisters – remains reproductively viable throughout life. A study from the University of Illinois ...

How cheating ants give themselves away

January 8, 2009

In ant society, workers normally give up reproducing themselves to care for their queen's offspring, who are their brothers and sisters. When workers try to cheat and have their own kids in the queen's presence, their peers ...

Recommended for you

Rare cells are 'window into the gut' for the nervous system

June 22, 2017

Specialized cells in the gut sense potentially noxious chemicals and trigger electrical impulses in nearby nerve fibers, according to a new study led by UC San Francisco scientists. "These cells are sensors, like a window ...

Cells in fish's spinal discs repair themselves

June 22, 2017

Duke researchers have discovered a unique repair mechanism in the developing backbone of zebrafish that could give insight into why spinal discs of longer-lived organisms like humans degenerate with age.

Biofilms—the eradication has begun

June 22, 2017

Have you ever heard of biofilms? They are slimy, glue-like membranes that are produced by microbes, like bacteria and fungi, in order to colonize surfaces. They can grow on animal and plant tissues, and even inside the human ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Sep 10, 2009
RE: Parthenogenesis in worker bees!?

Worker bees are generally unable to mate, but are capable of laying unfertilized eggs which can develop into male offspring.
Parthenogenesis is common in nature as explained here: http://en.wikiped...ogenesis . So, why Alves had to "anthropomorphize" bees as in the "selfish gene" fallacy, like so:
This demonstrates, for the first time, how workers continue this conflict by reproductively parasitizing the next-generation of the workforce for their own selfish benefit.

Best wishes, Mong 9/10/9usct3:10p; practical science-philosophy critic; author "Decoding Scientism" and "Consciousness & the Subconscious" (works in progress since July 2007), "Gods, Genes, Conscience" (2006: http://www.iunive...95379907 ) and "Gods, Genes, Conscience: Global Dialogues Now" (blogging avidly since 2006: http://www2.blogg...50569778 ).

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.