Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Communal living of the insect kind

17.11.2011
The social lives of ants, wasps and bees have long been a puzzle to scientists. How did complex insect societies — colonies ruled by a queen and many workers — come to be? A new model adds to discontent with old ideas.

Social insect society is divided into specialized castes that take on different roles within the nest. Most of the members of a colony – the workers – forego their own chance for reproduction and instead spend their lives raising offspring that aren't their own. Generations of scientists have tried to understand why. In other words, "what's in it for the workers?" said author James Hunt, who developed his model while at the National Evolutionary Synthesis Center in Durham, NC.

The question continues to spark debate. For the past 40 years, the dominant answer was based on the idea that having kids of your own isn't the only way to pass on your genes. According to a theory called Hamilton's rule, proposed in 1964 by British biologist William Hamilton, sometimes helping a relative can spread more of your genes to the next generation than having kids of your own. When the benefits to a queen outweigh the costs to her workers, the theory goes, altruism can evolve.

But there's one thing Hamilton's rule fails to consider. "Direct benefit to the worker is not part of the equation," Hunt said. According to Hunt, the evolutionary beginnings of worker behavior may be more selfish than they seem.

He bases his ideas on more than three decades of research on a family of wasps called the Vespidae, which is made up of nearly 5000 species. The majority of those species live alone, but some —such as hornets, yellowjackets, and paper wasps — live in complex societies with specialized castes that take on different tasks within the nest.

In paper wasps, for example, workers help build and defend the nest where they were born and feed and care for the larvae. By helping out around the nest, worker paper wasps are able to stock up on the food they need to eventually leave and lay eggs on their own, and the queen gets some babysitting help in return. "It's a situation of reciprocal exploitation," Hunt said.

Debates over how social behavior comes to be can be notoriously fierce in scientific circles. In recent years, a handful of studies have thrown Hamilton's rule into question, including a 2010 paper in the journal Nature that inspired dozens of scientists to write replies. Hunt's hypothesis says the 2010 study is basically correct, but it overplays the importance of genes.

Much of the debate stems from a failure to parse out key intermediate steps in the evolutionary transition from solitary to social, Hunt says. Paper wasps, for example, cooperate to care for young, but haven't yet evolved the distinct differences in appearance that characterize castes in the most highly social insects.

At these earliest stages, Hunt says, it doesn't matter whether workers and queens are related or not, or how many genes they share. The workers could be lingering around the nest simply because they're looking out for number one.

"The model that I'm putting forward proposes that at the very beginning of social behavior, the workers and the queens are both acting in their own self-interest," Hunt said.

The study will be published this week in the Journal of Evolutionary Biology.

CITATION: Hunt, J. "A conceptual model for the origin of worker behaviour and adaptation of eusociality." Journal of Evolutionary Biology.

For previous stories about this research and related work, read Zimmer, C. 2010. Scientists square off on evolutionary value of helping relatives. The New York Times. http://www.nytimes.com/2010/08/31/science/31social.html?_r=1

The National Evolutionary Synthesis Center (NESCent) is a science center dedicated to cross-disciplinary research in evolution. Funded by the National Science Foundation, NESCent is jointly operated by Duke University, The University of North Carolina at Chapel Hill, and North Carolina State University.

Robin Ann Smith | EurekAlert!
Further information:
http://www.nescent.org

More articles from Life Sciences:

nachricht Nanotubes built from protein crystals: Breakthrough in biomolecular engineering
15.11.2018 | Tokyo Institute of Technology

nachricht Insect Antibiotic Provides New Way to Eliminate Bacteria
15.11.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>