Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Social Wasps Show How Bigger Brains Provide Complex Cognition

13.04.2011
Across many groups of animals, species with bigger brains often have better cognitive abilities. But it’s been unclear whether overall brain size or the size of specific brain areas is the key.

New findings by neurobiologists at the University of Washington suggest that both patterns are important. The researchers found that bigger-bodied social wasps had larger brains and devoted up to three times more of their brain tissue to regions that coordinate social interactions, learning, memory and other complex behaviors.

Within a species, queens had larger central processing areas – the brain regions that manage complex behaviors – than did worker wasps.

“As the brain gets larger, there’s disproportionately greater investment in the size of brain tissue for higher-order cognitive abilities,” said Sean O’Donnell, lead author and UW psychology professor. “As larger wasp brains evolve, natural selection favors investing most heavily in the brain regions involved in learning and memory.”

For smaller-brained species, cognitive power may be limited by their inability to invest in central brain regions. “In many kinds of animals, it’s only with a larger brain – which is determined by body size – that more complex and flexible behaviors are achieved,” O’Donnell said.

The results appear in the April 11 online edition of the Proceedings of the National Academy of Sciences.

O’Donnell and his co-authors collected samples of 10 types of adult social wasps from four field sites in Costa Rica and Ecuador. As in other studies, they found that the larger the wasp, the larger the overall brain size. But increase of brain size was not uniform across all brain regions.

The researchers dissected the wasp brains and measured the volume of two brain regions. They focused on the central processing region known as the mushroom bodies that, like the cerebral cortex in humans, handles elaborate cognitive functions such as learning, memory and social interactions. They also measured the peripheral processing regions – the optic lobes and the antennal lobes – that deal with vision and smell and are thought to perform more basic cognitive functions.

Across the 10 species, brain areas that process peripheral sensory information increased only slightly with overall brain size. But the wasps with larger bodies – and correspondingly larger-sized brains – had disproportionately larger central processing regions.

“These findings suggest that absolute brain size matters a lot, because it sets limits on central cognitive processing tissue,” O’Donnell said.

The researchers also found that in nine out of 10 wasp species, the queens had larger central processors than worker wasps. This was surprising to the researchers because, in social wasps, queens seem to not perform complex tasks like food collection. They’re relatively inactive, staying in the nest to lay eggs while the workers go out to forage.

But O’Donnell said the greater brain power possessed by social wasp queens may be due to having to defend their social status. “Queens are constantly tested for their potency. They must be up for those social cognitive demands,” he said.

The researchers are now testing the prediction that large-brained species will have enhanced cognitive abilities compared with smaller-brained species, which could have ecological payoffs for challenges like invading new habitats and expanding their geographic range.

The National Science Foundation and the Society for Integrative & Comparative Biology funded the study. Co-authors are Yamile Molina, who received a doctorate in psychology at UW, and Marie Clifford, a UW biology graduate student.

For more information, contact O’Donnell at sodonnel@uw.edu or 206-543-2315.
For photos, Molly McElroy: mollywmc@uw.edu or 206-543-2580.

O’Donnell | Newswise Science News
Further information:
http://www.uw.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

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 “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>