Navigation Links
Like humans, ants use bacteria to make their gardens grow
Date:11/19/2009

MADISON Leaf-cutter ants, which cultivate fungus for food, have many remarkable qualities.

Here's a new one to add to the list: the ant farmers, like their human counterparts, depend on nitrogen-fixing bacteria to make their gardens grow. The finding, reported this week (Nov. 20) in the journal Science, documents a previously unknown symbiosis between ants and bacteria and provides insight into how leaf-cutter ants have come to dominate the American tropics and subtropics.

What's more, the work, conducted by a team led by University of Wisconsin-Madison bacteriologist Cameron Currie, identifies what is likely the primary source of terrestrial nitrogen in the tropics, a setting where nutrients are otherwise scarce.

"Nitrogen is a limiting resource," says Garret Suen, a UW-Madison postdoctoral fellow and a co-author of the new study. "If you don't have it, you can't survive."

Indeed, the partnership between ant and microbe permits leaf-cutters to be amazingly successful. Their underground nests, some the size of small houses, can harbor millions of inhabitants. In the Amazon forest they comprise four times more biomass than do all land animals combined.

"This is the first indication of bacterial garden symbionts in the fungus-growing ant system," says Currie, a UW-Madison professor of bacteriology.

A critical finding in the new study, according to the Wisconsin scientist, is that the nitrogen, which is extracted from the air by the bacteria, ends up in the ants themselves and, ultimately, benefits the nitrogen-poor ecosystems where the ants thrive.

The fungus-growing ants, Currie notes, are technically herbivores. They make their living by carving up foliage and carrying it back to their nests in endless columns to provide the raw material for the fungus they grow as food. "But plant-feeding insects are known to be nitrogen limited," explains Currie, "and the plant biomass nitrogen is lower than what the insects need for survival."

Enter the nitrogen-fixing bacteria, two species of which were isolated in laboratory and field colonies of the ants. But merely finding the bacteria, Suen emphasizes, wasn't enough. It was necessary to prove that the ants were actually utilizing the nutrient to confirm a true mutualism.

"This is important because it could be that the bacteria are fixing nitrogen for themselves and not actually benefiting the ants," says Suen. "Showing that the nitrogen fixed by the bacteria is incorporated into the ants establishes that these bacteria aren't just transient visitors."

One other type of insect, the termite, has been previously shown to utilize nitrogen-fixing bacteria. And other bacteria-ant symbioses have been documented.

However, the discovery of the nitrogen-fixing mutualism in ants has significant ecological implications given the dominance of ants in virtually all of the word's terrestrial ecosystems. The new work suggests that an important source of nitrogen in the American tropics and subtropics is derived through the partnership of ant and bacteria.

Says Currie: "It is possible that this fixed nitrogen can have ecosystem scale impacts."

The partnership with bacteria, which Currie says could extend back to the origins of the gardening ants some 50 million years ago, confers a competitive edge that has permitted the leaf-cutters to prevail in their environments.

Says Suen: "Without nitrogen, there is no way these guys could achieve such large colony sizes. These ants are one of the most dominant insects in the Neotropics. The ability to have colonies with millions of ants is predicted to require a tremendous amount of nitrogen."


'/>"/>

Contact: Cameron Currie
currie@bact.wisc.edu
608-265-8034
University of Wisconsin-Madison
Source:Eurekalert

Related biology news :

1. Like humans, monkeys fall into the uncanny valley
2. Key feature of immune system survived in humans, other primates for 60 million years
3. Dogs, humans, put heads together to find cure for brain cancer
4. Why some primates, but not humans, can live with immunodeficiency viruses and not progress to AIDS
5. Like humans, monkey see, monkey plan, monkey do
6. Texas A&M Researchers Examine How Viruses Destroy Bacteria
7. Bacterial ropes tie down shifting Southwest
8. Bacteria launch a shield to resist attack
9. Boston University scientists first to see RNA network in live bacterial cells
10. Eating right, not supplements, is best at keeping your good bacteria healthy, dietitian says
11. Researchers discover RNA repair system in bacteria
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/18/2017)... SUNNYVALE, Calif. , April 18, 2017  Socionext Inc., a ... prototype of a media edge server, the M820, which features the ... face recognition software provided by Tera Probe, Inc., will be showcased ... and at the NAB show at the Las Vegas ... ...
(Date:4/13/2017)... -- According to a new market research report "Consumer IAM ... and Authorization), Service, Authentication Type, Deployment Mode, Vertical, and Region - Global ... grow from USD 14.30 Billion in 2017 to USD 31.75 Billion by ... ... MarketsandMarkets Logo ...
(Date:4/11/2017)... , April 11, 2017 No two ... researchers at the New York University Tandon School ... Engineering have found that partial similarities between prints ... used in mobile phones and other electronic devices ... The vulnerability lies in the fact that ...
Breaking Biology News(10 mins):
(Date:7/25/2017)... ... 2017 , ... Fiberstar, Inc ., a global market leader in clean ... natural citrus fiber is used to improve tomato-based food products by replacing starches and ... spreads. Today, more than ever, consumers connect ingredients to the foods they eat by ...
(Date:7/24/2017)... ... 24, 2017 , ... Each year, Inavero’s Best of Staffing® ... superior service quality as rated by hiring professionals and job candidates. In its ... service quality ratings from their placed talent. , Fewer than 2% of all ...
(Date:7/20/2017)... ... July 20, 2017 , ... Litmus Health , a ... full advisory board. The board comprises leaders spanning business, technology, academia, and pharmaceutical ... VP of Engineering, to Chief Technology Officer. Crooks will lead strategy and development ...
(Date:7/20/2017)... Reno, NV (PRWEB) , ... July 20, 2017 ... ... a real solution to make clinical trial sites and study participants truly unified. ... manage regulatory compliant (FDA 21 CFR Part 11) research studies entirely on mobile ...
Breaking Biology Technology: