Temporary infidelity may contribute to the stability of ancient relationships

June 1, 2009
Acromyrmex ant queens usually start a new fungal garden with a bit of fungus from their natal nest, but sometimes the end up cultivating another fungal clone. Credit: Sophie A.O. Armitage

Partner switching between fungus farming ants and their fungal clones during nest establishment may contribute to the stability of this long-term mutualistic relationship.

Fungus-farming ants have cultivated the same fungal crops for 50 million years. Each young ant queen carries a bit of garden with her when she flies away to mate and establish a new nest. Short breaks in the ants' relationship with the fungus during nest establishment may contribute to the stability of this long-term mutualism, according to a study at the Smithsonian Tropical Research Institute in Gamboa, Panama.

"We were struck by the paradox that even though the ants transfer a single fungal strain from generation to generation, nests of different ant species, and even genera, throughout Central America share genetically very similar fungi, indicating that there are exchanges going on between fungi from different nests," said Michael Poulsen, who held a Smithsonian short term fellowship while a doctoral student at the University of Copenhagen. "In these experiments, we found that there is a very short window of time--as the young queen establishes a new nest--when partner switching can occur."

in the genus Acromyrmex cultivate a single fungal species in their nests: Leucoagaricus gonglyophorus. Mature contain one fungal clone--a single , which uses several strategies to make sure that other fungi do not invade.

Researchers noticed that several queens from different colonies sometimes start very close together and wondered if young queens were given fungi from a nest other than their natal nest—would they treat it as their own fungal crop?

"That's exactly what happens," said Poulsen, now research associate at the University of Wisconsin. "Young queens adopt a fungus from another nest and cultivate it in their new nest. This sort of temporary partner switching probably acts as an evolutionary safety net in the ant-fungus mutualism by preventing the accumulation of deleterious mutations."

The study is published in the journal Evolution.

Source: Smithsonian Tropical Research Institute

Explore further: Long-term co-evolution stability studied

Related Stories

Long-term co-evolution stability studied

June 27, 2006

U.S. biologists say the world's fungus-farming ants cultivate essentially the same fungus and aren't as critical to fungi reproduction as had been thought.

Scientists reveal ants as fungus farmers

March 24, 2008

It turns out ants, like humans, are true farmers. The difference is that ants are farming fungus. Entomologists Ted Schultz and Seán Brady at the Smithsonian’s National Museum of Natural History have published a paper ...

Farming and chemical warfare: A day in the life of an ant?

November 17, 2008

One of the most important developments in human civilisation was the practice of sustainable agriculture. But we were not the first - ants have been doing it for over 50 million years. Just as farming helped humans become ...

How house-hunting ants choose the best home

April 22, 2009

(PhysOrg.com) -- Direct comparison of alternatives isn’t always the best way to make a decision - at least if you’re an ant. House-hunting rock ants collectively manage to choose the best nest-site without needing to ...

Recommended for you

Humans account for little next to plants, worms, bugs

May 21, 2018

When you weigh all life on Earth, billions of humans don't amount to much compared to trees, earthworms or even viruses. But we really know how to throw what little weight we have around, according to a first-of-its-kind ...

Study finds snap-lock mechanism in bacterial riboswitch

May 21, 2018

In a discovery that points to potential new antibiotic medicines, scientists from Rice University and the University of Michigan have deciphered the workings of a common but little-understood bacterial switch that cuts off ...

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.