Navigation Links
Snakes on the brain: Are primates hard-wired to see snakes?
Date:10/28/2013

Was the evolution of high-quality vision in our ancestors driven by the threat of snakes? Work by neuroscientists in Japan and Brazil is supporting the theory originally put forward by Lynne Isbell, professor of anthropology at the University of California, Davis.

In a paper published Oct. 28 in the journal Proceedings of the National Academy of Sciences, Isbell; Hisao Nishijo and Quan Van Le at Toyama University, Japan; and Rafael Maior and Carlos Tomaz at the University of Brasilia, Brazil; and colleagues show that there are specific nerve cells in the brains of rhesus macaque monkeys that respond to images of snakes.

The snake-sensitive neurons were more numerous, and responded more strongly and rapidly, than other nerve cells that fired in response to images of macaque faces or hands, or to geometric shapes. Isbell said she was surprised that more neurons responded to snakes than to faces, given that primates are highly social animals.

"We're finding results consistent with the idea that snakes have exerted strong selective pressure on primates," Isbell said.

Isbell originally published her hypothesis in 2006, following up with a book, "The Fruit, the Tree and the Serpent" (Harvard University Press, 2009) in which she argued that our primate ancestors evolved good, close-range vision primarily to spot and avoid dangerous snakes.

Modern mammals and snakes big enough to eat them evolved at about the same time, 100 million years ago. Venomous snakes are thought to have appeared about 60 million years ago "ambush predators" that have shared the trees and grasslands with primates.

Nishijo's laboratory studies the neural mechanisms responsible for emotion and fear in rhesus macaque monkeys, especially instinctive responses that occur without learning or memory. Previous researchers have used snakes to provoke fear in monkeys, he noted. When Nishijo heard of Isbell's theory, he thought it might explain why monkeys are so afraid of snakes.

"The results show that the brain has special neural circuits to detect snakes, and this suggests that the neural circuits to detect snakes have been genetically encoded," Nishijo said.

The monkeys tested in the experiment were reared in a walled colony and neither had previously encountered a real snake.

"I don't see another way to explain the sensitivity of these neurons to snakes except through an evolutionary path," Isbell said.

Isbell said she's pleased to be able to collaborate with neuroscientists.

"I don't do neuroscience and they don't do evolution, but we can put our brains together and I think it brings a wider perspective to neuroscience and new insights for evolution," she said.


'/>"/>

Contact: Andy Fell
ahfell@ucdavis.edu
530-752-4533
University of California - Davis
Source:Eurekalert

Related biology news :

1. New paper examines poison resistance in snakes around the world
2. Robosquirrels versus rattlesnakes
3. Big-mouthed babies drove the evolution of giant island snakes
4. Scientists discover new type of virus responsible for a devastating disease in snakes
5. Snakes minus birds equals more spiders for Guam
6. Global warming beneficial to ratsnakes
7. Scientists discover reasons behind snakes shrinking heads
8. Snakes devour more mosquito-eating birds as climate change heats forests
9. Protecting your brain: Use it or lose it
10. Good news for nanomedicine: Quantum dots appear safe in pioneering study on primates
11. Manipulation of a specific neural circuit buried in complicated brain networks in primates
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/2/2016)... June 2, 2016   The Weather Company , an ... Ads, an industry-first capability in which consumers will be able ... to ask questions via voice or text and receive relevant ... Marketers have long sought an advertising solution ... can be personal, relevant and valuable; and can scale across ...
(Date:6/1/2016)... YORK , June 1, 2016 ... Technology in Election Administration and Criminal Identification to Boost ... to a recently released TechSci Research report, " Global ... By Region, Competition Forecast and Opportunities, 2011 - 2021", ... 24.8 billion by 2021, on account of growing security ...
(Date:5/20/2016)... , May 20, 2016  VoiceIt is excited ... with VoicePass. By working together, VoiceIt ...  Because VoiceIt and VoicePass take slightly different approaches ... increases both security and usability. ... about this new partnership. "This marketing ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... Mosio, a leader ... “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with experienced clinical research professionals, ... providing practical tips, tools, and strategies for clinical researchers. , “The landscape of ...
(Date:6/23/2016)... , June 23, 2016 Houston Methodist ... the Cy-Fair Sports Association to serve as their ... agreement, Houston Methodist Willowbrook will provide sponsorship support, ... connectivity with association coaches, volunteers, athletes and families. ... the Cy-Fair Sports Association and to bring Houston ...
(Date:6/23/2016)... , ... June 23, 2016 , ... ... announced the launch of the Supplyframe Design Lab . Located in Pasadena, ... explore the future of how hardware projects are designed, built and brought to ...
(Date:6/23/2016)... LONDON , June 23, 2016 ... & Hematology Review, 2016;12(1):22-8 http://doi.org/10.17925/OHR.2016.12.01.22 ... Review , the peer-reviewed journal from touchONCOLOGY, ... the escalating cost of cancer care is placing ... a result of expensive biologic therapies. With the ...
Breaking Biology Technology: