Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Symbiotic fungus does not depend on fungus-farming ants for reproduction, researchers say

28.06.2006
Fungus-farming ants around the world cultivate essentially the same fungus and are not as critical to the reproduction of the fungi as previously believed, biologists at The University of Texas at Austin have discovered.

Fungus-farming ants are dependent on cultivating fungus gardens for food, and it has been widely believed the fungi also evolved dependence on the ants for their dispersal and reproduction. When young ant queens establish new colonies, they take a start-up crop of fungi with them from their parental garden.


A leaf-cutting ant queen (Acromyrmex coronatus) is sheltered in a chamber deep inside of her fungus garden, made of leaf fragments and strands of a symbiotic fungus. The garden was grown from a few strands brought by the queen on her mating flight from the maternal garden. After the mating flight, the queen never leaves her garden metropolis. Credit: Alexander Mikheyev and Barrett Klein

Graduate student Alexander Mikheyev and Dr. Ulrich Mueller, professor of integrative biology, have now found that the fungi reproduce sexually and disperse widely without the aid of their ant farmers.

Different genera of the ants, it turns out, are essentially cultivating the same fungus across wide geographical areas.

The scientists' finding provides a new perspective on coevolutionary processes. Coevolution, like that between honeybees and the flowers they pollinate, occurs when two or more species influence each other's evolution over time. Mikheyev says that two species don't necessary need to have a very specific, one-to-one relationship in order to coevolve.

"This shows that coevolution can proceed without specificity at the species level," said Mikheyev. "It has been believed that mutualistic interactions, as well as parasitic ones, are very specific and one-to-one. We are beginning to realize that this is not necessary for long-term coevolutionary stability, with the leaf-cutting ants being a dramatic example."

The research was published June 26 in Proceedings of the National Academy of Sciences.

"Previously, the fungi were thought to be passive players, moved around by the ants," said Mikheyev. "We show that the power of fungal dispersal is probably beyond ant control."

Observations of the fungi reproducing sexually--producing a fruiting body or mushroom--deep inside an ant nest are extremely rare. So the scientists, in collaboration with Dr. Patrick Abbot at Vanderbilt University, read the signatures of sexual reproduction in the fungal genes. They studied fungi cultivated by leaf-cutting ants, well known fungus farmers that bring pieces of leaves back to their nest to use as a growth medium for their fungi.

Genetic analysis revealed that the fungi are still using the cellular machinery necessary for sexual reproduction, which would have been lost or changed had the fungi become completely dependent on asexual, clonal reproduction through their ant farmers.

Studying the fungus gardens of an introduced population of leaf-cutting ants on the French Caribbean island of Guadeloupe, the scientists also found that the fungal genes have been recombining, a sign they are reproducing with one another.

"The fungi are not completely domesticated and under the strict control of the ants," said Mueller. "Instead, the fungi occasionally have a life of their own, dispersing independently of the ants and exchanging genes with other ant-cultivated fungi."

Mikheyev, Mueller and Abbot also compared leaf-cutter ants and their fungal crops from Cuba to populations of ants and fungi from Central and South America. Though the Cuban ants have been isolated from mainland populations for many years, genetic analysis showed their fungal crops have been exchanging genes with mainland fungi populations.

"The fungi are able to cross geographical boundaries too great for the ants, intermingling genes between mainland and Cuban populations, possibly through airborne spores," said Mikheyev.

Ulrich Mueller | EurekAlert!
Further information:
http://www.utexas.edu

More articles from Life Sciences:

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

nachricht If solubilty is the problem - Mechanochemistry is the solution
25.05.2018 | Technische Universität Dresden

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

If solubilty is the problem - Mechanochemistry is the solution

25.05.2018 | Life Sciences

Investigating cell membranes: researchers develop a substance mimicking a vital membrane component

25.05.2018 | Interdisciplinary Research

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

VideoLinks
Science & Research
Overview of more VideoLinks >>>