Featured Research

from universities, journals, and other organizations

Tiny But Adaptable Wasp Brains Show Ability To Alter Their Architecture

Date:
October 15, 2009
Source:
University of Washington
Summary:
For an animal that has a brain about the size of two grains of sand, a lot of plasticity seems to be packed into the head of the tropical paper wasp Polybia aequatorialis.

Photographs of brain neuron dendrite branches from paper wasps (Polybia aequatorialis). Typical neurons from each of the three main behavioral classes of workers are shown. Note the increasing dendrite branch length and complexity going from in-nest to foraging workers. The neurons were made visible using a technique called Golgi staining, which makes all of the complex branches of some neurons visible against a transparent background. The dashed outlines indicate the border of the brain region where these neurons' dendrites branch. This is where the neurons connect and receive information from other areas of the brain.
Credit: Courtesy of Sean O'Donnell / University of Washington

For an animal that has a brain about the size of two grains of sand, a lot of plasticity seems to be packed into the head of the tropical paper wasp Polybia aequatorialis.

Researchers from the universities of Washington and Texas have found that the brain architecture of these wasps undergoes dramatic changes as they cycle through a sequence of specialized jobs during their lives. The scientists previously had discovered that parts of the brains of this wasp species enlarged as the animal engage in more complex tasks.

The new work describes how this happens as dendrites, or extensions from individual neurons, reach out to receive information from other brain cells and form a dense network of connections. These networks help the wasps integrate information from visual, olfactory and touch sensory systems.

"I was astounded when we found that some of the individual neurons had dendrites that were seven to eight millimeters long in a brain that is roughly the size of two grains of sand. That's packing a huge amount of computing power in a small amount of space," said Sean O'Donnell, a UW associate professor of psychology and co-author of the new study. "These animals live in a complicated world and individuals face challenges that require a lot of brain power."

Co-authors of the paper are Theresa Jones, a UT associate professor of psychology, and Nicole Donlan, a UT research associate.

"The architecture of the wasp brain is different from that in humans," said O'Donnell. "They evolved independently from us, but some of the problems they face are similar to ours because both of us are social animals. This gives researchers the opportunity to ask if there are similarities or differences in brain plasticity for social animals."

P. aequatorialis wasps live in colonies of 2,000 or more adults. The adult workers perform different jobs for the colony in a developmental sequence that is accompanied by behavioral changes as they age. They begin by performing tasks in the dim interior of the nest before moving outside where they work on the exterior of the nest. Finally, they leave the nest to forage for food and building materials for the colony and then find their way back to the nest. Each job change is accompanied by an increase in the complexity of the tasks.

The researchers found the biggest changes in brain neuron architecture occurred when the wasps shifted from working on the nest exterior to foraging.

"The forager brain is quite different. The neuron dendrite network is more complex and dense than for other job classes," said O'Donnell. "These brain changes seem to be a semipermanent way for the animals to deal with the cognitive challenges they are facing. Our earlier work showed that once workers change jobs they don't go back to previous tasks. It is plausible that they do not have the cognitive ability to do the old tasks."

He said the change in environment encountered by wasps as they develop is comparable to what people face over the course of a day. People wake up in the familiar environment of the home and family, but once they leave for home or school they face the tasks of driving a car or taking the bus in more complex environments where there are many unfamiliar people, traffic and a lot more stimulation.

Exactly what spurs the changes of the dendrite branches isn't known yet, but the researchers suspect increasing light levels outside the nest may trigger the some of changes in brain architecture. In a part of the brain that processes visual input, the neuron branches actually shrank during the on-nest phase of life, only to rebound to even greater size during the foraging phase. This shrinkage, or "pruning" of neuron branches may prepare the brain for later neuron growth to even larger sizes, perhaps also allowing new connections to form. These changes allow the wasps to function in a new environment that has different cognitive challenges.

The research was funded by the National Science Foundation and published in the online edition of the journal Neurobiology of Learning and Memory.


Story Source:

The above story is based on materials provided by University of Washington. Note: Materials may be edited for content and length.


Journal Reference:

  1. Theresa A. Jones, Nicole A. Donlan, Sean O'Donnell. Growth and pruning of mushroom body Kenyon cell dendrites during worker behavioral development in the paper wasp, Polybia aequatorialis (Hymenoptera: Vespidae). Neurobiology of Learning and Memory, 2009; 92 (4): 485 DOI: 10.1016/j.nlm.2009.06.007

Cite This Page:

University of Washington. "Tiny But Adaptable Wasp Brains Show Ability To Alter Their Architecture." ScienceDaily. ScienceDaily, 15 October 2009. <www.sciencedaily.com/releases/2009/10/091014144738.htm>.
University of Washington. (2009, October 15). Tiny But Adaptable Wasp Brains Show Ability To Alter Their Architecture. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/2009/10/091014144738.htm
University of Washington. "Tiny But Adaptable Wasp Brains Show Ability To Alter Their Architecture." ScienceDaily. www.sciencedaily.com/releases/2009/10/091014144738.htm (accessed August 30, 2014).

Share This




More Mind & Brain News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Treadmill 'trips' May Reduce Falls for Elderly

Treadmill 'trips' May Reduce Falls for Elderly

AP (Aug. 28, 2014) Scientists are tripping the elderly on purpose in a Chicago lab in an effort to better prevent seniors from falling and injuring themselves in real life. (Aug.28) Video provided by AP
Powered by NewsLook.com
Alice in Wonderland Syndrome

Alice in Wonderland Syndrome

Ivanhoe (Aug. 27, 2014) It’s an unusual condition with a colorful name. Kids with “Alice in Wonderland” syndrome see sudden distortions in objects they’re looking at or their own bodies appear to change size, a lot like the main character in the Lewis Carroll story. Video provided by Ivanhoe
Powered by NewsLook.com
Stopping Schizophrenia Before Birth

Stopping Schizophrenia Before Birth

Ivanhoe (Aug. 27, 2014) Scientists have long called choline a “brain booster” essential for human development. Not only does it aid in memory and learning, researchers now believe choline could help prevent mental illness. Video provided by Ivanhoe
Powered by NewsLook.com
Personalized Brain Vaccine for Glioblastoma

Personalized Brain Vaccine for Glioblastoma

Ivanhoe (Aug. 27, 2014) Glioblastoma is the most common and aggressive brain cancer in humans. Now a new treatment using the patient’s own tumor could help slow down its progression and help patients live longer. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins