Featured Research

from universities, journals, and other organizations

How Crayfish Do The Locomotion?

Date:
November 29, 2002
Source:
University Of California - Davis
Summary:
Using computer models and experiments, researchers at the University of California, Davis, have identified the neurons and connections that are necessary for crayfish to swim.

Using computer models and experiments, researchers at the University of California, Davis, have identified the neurons and connections that are necessary for crayfish to swim.

Related Articles


"We can now pin down the essential components of the circuit," said Brian Mulloney, a professor of neurobiology, physiology and behavior at UC Davis.

The nervous system controlling locomotion is highly tuned and very stable across different groups of animals, Mulloney said. That makes crayfish a good model for much more complex nervous systems such as the human spinal cord.

New advances in the field were discussed in a session chaired by Mulloney at the Society for Neuroscience meeting in November 2002.

Crayfish swim by beating pairs of paddles called swimmerets on each body segment. The swimmerets move in sequence, starting at the back of the animal and moving forward. The movements of each segment keep a precise difference in timing, while varying in speed and force.

To keep those movements in the right sequence, the animal's nervous system has to integrate signals from each of these different segments as well as signals from the brain.

Mulloney's group, working with mathematicians Stephanie Jones at Harvard University and Frances Skinner at the University of Toronto, built mathematical models of the crayfish nervous system to see how they might work. They used those models to design experiments where they recorded impulses in crayfish nerves.

They showed that the swimmeret system is made up of eight modules of 70 neurons each. They found which neurons are necessary to complete the circuit, and what cells they connect to.

As the swimmerets beat, each module receives a stream of nerve impulses from the modules behind and in front of it. Signals from behind indicate a power stroke; those from the front represent a recovery stroke. Mulloney's team has found that those different messages converge on the same target neuron, which integrates them into a graded, non-spiking signal. This combined signal tells the module when to release neurotransmitters -- chemicals which change the timing and force of limb movement.

The same basic plan is likely found in insects and other animals, Mulloney said.


Story Source:

The above story is based on materials provided by University Of California - Davis. Note: Materials may be edited for content and length.


Cite This Page:

University Of California - Davis. "How Crayfish Do The Locomotion?." ScienceDaily. ScienceDaily, 29 November 2002. <www.sciencedaily.com/releases/2002/11/021126200852.htm>.
University Of California - Davis. (2002, November 29). How Crayfish Do The Locomotion?. ScienceDaily. Retrieved February 27, 2015 from www.sciencedaily.com/releases/2002/11/021126200852.htm
University Of California - Davis. "How Crayfish Do The Locomotion?." ScienceDaily. www.sciencedaily.com/releases/2002/11/021126200852.htm (accessed February 27, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, February 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Amazon Keeps Its Green Thanks To The Sahara Desert

The Amazon Keeps Its Green Thanks To The Sahara Desert

Newsy (Feb. 25, 2015) Satellite data shows the Amazon rainforest supports its lush flora with a little help from Sahara Desert dust. Video provided by Newsy
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Marijuana Nowhere Near As Deadly As Alcohol: Study

Marijuana Nowhere Near As Deadly As Alcohol: Study

Newsy (Feb. 25, 2015) A new study says marijuana is about 114 times less deadly than alcohol. Video provided by Newsy
Powered by NewsLook.com
Fox With Horrifying Injury Rescued and Released Back Into the Wild

Fox With Horrifying Injury Rescued and Released Back Into the Wild

RightThisMinute (Feb. 25, 2015) This wounded fox knew what she was doing when she wandered into the yard of a nature photographer. The photographer got "Scamp" immediately in the hands of Wildlife Aid and she was released back into the wild in no time. Video provided by RightThisMinute
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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