Genetic diversity in honeybee colonies boosts productivity

July 20, 2007
Genetic diversity in honeybee colonies boosts productivity
Worker honeybees construct a new comb, an important part of colony founding. Colonies of promiscuous queens tend to be far more successful in such chores and in surviving their first winter than colonies produced by monogamous queens, report Cornell researchers Tom Seeley and Heather Mattila in Science magazine. Credit: Heather R. Mattila/Cornell University

Why do queen honeybees mate with dozens of males? Does their extreme promiscuity, perhaps, serve a purpose?

An answer to this age-old mystery is proposed in the July 20 issue of Science magazine by Cornell scientists: Promiscuous queens, they suggest, produce genetically diverse colonies that are far more productive and hardy than genetically uniform colonies produced by monogamous queens.

"An intriguing trait of honeybee species worldwide is that each honeybee queen mates with an extraordinarily high number of males," said Heather R. Mattila, a Cornell postdoctoral fellow in neurobiology and behavior and co-author of the article with Thomas D. Seeley, Cornell professor of neurobiology and behavior.

In every honeybee species, say the researchers, queens mate with multiple males. The European honeybee -- the common species in North America -- mates with from six to 20 mates on average, for example, while the giant honeybee in Asia has a reported record of 102 mates.

To study the reasons for honeybees' promiscuity, the Cornell biologists inseminated 12 queens with sperm from 15 drones (a different set for each) and nine additional queens with sperm from a single drone (but a different one in each case). They then prompted the hives to swarm in early June to form new colonies.

"After only two weeks of building new nests, the genetically diverse colonies constructed 30 percent more comb, stored 39 percent more food and maintained foraging levels that were 27 to 78 percent higher than genetically uniform colonies," said Mattila.

By the end of the summer, the genetically diverse colonies had five times more bees, eight times more reproductive males and heavier average body weights, mostly because of larger amounts of stored food.

By winter's end, 25 percent of the genetically diverse colonies survived to their one-year anniversary (only about 20 percent of new honeybee colonies make it that long in upstate New York). But all of the genetically uniform hives starved to death.

"These differences are noteworthy considering colonies had similarly sized worker populations when they were first formed," said Mattila. "Undoubtedly, our results reveal enormous benefits of genetic diversity for the productivity of honeybee colonies."

For example, the researchers found that bees in the genetically diverse colonies used sophisticated mechanisms for communication, including waggle dancing, more often than bees in genetically uniform colonies to discover food sources and direct nest mates to food. Because there was more information available among nest mates about food discoveries, the diverse colonies gained far more weight than did genetically uniform colonies.

Source: Cornell University

Explore further: The continuing plight of the honeybee

Related Stories

Latest suspect in colony disorder: Australian honeybees

June 22, 2010

Disease-carrying honeybees imported from Australia may be responsible for a mysterious disorder that's decimated bee hives around the country, and federal regulators say they'd consider import restrictions if necessary.

Sex life may hold key to honeybee survival

September 14, 2009

The number and diversity of male partners a queen honeybee has could help to protect her children from disease, say University of Leeds scientists, who are investigating possible causes of the widespread increase in bee deaths ...

How does a honeybee queen avoid inbreeding in her colony?

April 29, 2015

Recombination, or crossing-over, occurs when sperm and egg cells are formed and segments of each chromosome pair are interchanged. This process plays an crucial role in the maintanance of genetic variation. Matthew Webster ...

Bumblebee genomes give insights into threats to pollinators

April 23, 2015

The first full genome sequences of two bumblebee species are published this week in the open access journal Genome Biology. They give insights into the genetic basis and evolution of important aspects of bumblebee biology ...

Killer bees test a double win for Australian honeybees

April 21, 2015

A genetic test that can prevent the entry of 'killer' bees into Australia and worldwide spread has been created by researchers at the University of Sydney and their collaborators at York University in Canada.

Recommended for you

A cataclysmic event of a certain age

July 27, 2015

At the end of the Pleistocene period, approximately 12,800 years ago—give or take a few centuries—a cosmic impact triggered an abrupt cooling episode that earth scientists refer to as the Younger Dryas.

New blow for 'supersymmetry' physics theory

July 27, 2015

In a new blow for the futuristic "supersymmetry" theory of the universe's basic anatomy, experts reported fresh evidence Monday of subatomic activity consistent with the mainstream Standard Model of particle physics.

Dense star clusters shown to be binary black hole factories

July 29, 2015

The coalescence of two black holes—a very violent and exotic event—is one of the most sought-after observations of modern astronomy. But, as these mergers emit no light of any kind, finding such elusive events has been ...

0 comments

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.