Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brain, behavior may have changed as social insect colonies evolved

17.11.2006
A new study suggests that brain and behavior relationships may have changed in a profound way as larger, more complex insect societies evolved from smaller, simpler ones.

Researchers headed by Sean O'Donnell, a University of Washington associate professor of psychology, found that a key region in the brains of a primitively social paper wasp is better developed in dominant females than in subordinate ones.

"This finding, the first of its kind, contrasts with most of the prior work on social insect brain development. Earlier studies, including one of ours, were done on highly social species with large colony sizes. Among these species, age plays an important role in task performance and workers that leave the nest to forage generally have better-developed brains," he said.

"We found the opposite pattern with a primitively social wasp. Here, the stay-at-home dominant females had better brain development. In this species, direct dominance interactions among the females dictate task performance. Dominance and social interactions were more important than foraging tasks in explaining brain development."

In the new study, O'Donnell and colleagues from the University of Texas studied the brain development of the primitively social wasp Mischocyttarus mastigophorus in the tropical cloud forest near Monteverde, Costa Rica. These wasps live in colonies ranging in size from a handful to several dozen individuals where the division of labor is governed by aggression. The researchers examined an area of the insects' brain called the mushroom bodies. There is one mushroom body on top of each hemisphere of the wasp brain and these structures have a vague resemblance to the cerebrum in human and other vertebrates. The researchers were particularly interested in the calyx, a part of the mushroom body where neural connections are made.

The researchers collected and marked individuals including the queens from seven wasp nests, and observed their behavior. Later these individuals were recaptured and their brains were examined. Data showed that calyces were larger among the queens and the stay-at-home females. This is the opposite of what a number of researchers have found among highly social species with large colonies sizes. Several years ago, O'Donnell and his UT collaborators found that among Polybia aequatorialis, a highly social wasp that also lives in the same region of Costa Rica, there is more individual work specialization and individuals take on a sequence of jobs as they age. In such highly social species, workers that leave the nest to forage generally have better-developed brains.

"It seems pretty clear that primitively social colonies were the ancestral condition and that highly social colonies developed and evolved from them, said O'Donnell. He added that what is intriguing is that the pattern of brain development found in Polybia, a highly social group of wasps, is the same as in honey bees, another highly social insect.

"This shows that what job you do puts pressure on brain development in the highly social species," he said. "In contrasts, status seems to be the major brain demand in the primitively social species. This research suggests that task behavior and brain development has changed in a fundamental way between primitively social and the larger more complex social insect colonies."

The work is important because O'Donnell said social insects are a great model for understanding the design of brains and the relationship between brain design and social complexity. "And it has implications for human society because the evolution of our own society may affect brain development. Social behavior places pretty heavy demands on the human brain."

Joel Schwarz | EurekAlert!
Further information:
http://www.washington.edu

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

Im Focus: Autonomous 3D scanner supports individual manufacturing processes

Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).

Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Fingerprints of quantum entanglement

16.02.2018 | Information Technology

'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers

16.02.2018 | Health and Medicine

Hubble sees Neptune's mysterious shrinking storm

16.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>