Featured Research

from universities, journals, and other organizations

Study demonstrates that one extinction leads to another

Date:
August 14, 2012
Source:
University of Exeter
Summary:
When a carnivore becomes extinct, other predatory species could soon follow, according to new research. Scientists have previously put forward this theory, but now biologists have carried out the first experiment to show it. The study shows how the demise of one carnivore species can indirectly cause another to become extinct. The research team believes any extinction can create a ripple effect across a food web, with far-reaching consequences for many other animals.

A parasitic wasp attacks an aphid in the first study to prove the theory that the extinction of one predator can lead to the extinction of another.
Credit: Dirk Sanders

When a carnivore becomes extinct, other predatory species could soon follow, according to new research. Scientists have previously put forward this theory, but a University of Exeter team has now carried out the first experiment to prove it.

Published August  15, 2012 in the Royal Society journal Biology Letters, the study shows how the demise of one carnivore species can indirectly cause another to become extinct. The University of Exeter team believes any extinction can create a ripple effect across a food web, with far-reaching consequences for many other animals.

The research adds weight to growing evidence that a 'single species' approach to conservation, for example in fisheries management, is misguided. Instead the focus needs to be holistic, encompassing species across an entire ecosystem.

The researchers bred two species of parasitic wasps, along with the two types of aphids on which each wasp exclusively feeds. They set up tanks with different combinations of the species and observed them for eight weeks. In tanks that did not include the first species of wasp, the second went extinct within a few generations. In tanks in which they co-existed, both wasp species thrived.

In the absence of the first wasp species, its prey grew in numbers. This threatened the other aphid, which the second wasp species attacks, eventually leading to its extinction. Both types of aphids feed on the same plants and there was not enough food for one to survive when the other thrived in the absence of its wasp predator.

Lead researcher Dr Frank van Veen of the University of Exeter's Centre for Ecology and Conservation said: "Our experiment provides the first proof of something that biologists have argued for a long time: predators can have indirect effects on each other, to the extent that when one species is lost, the loss of these indirect effects can lead to further extinctions. Although our study focused on insects, the principle would be the same for predators in any ecosystem, ranging from big cats on the African plains to fish in our seas.

"Our research highlights the fact that a 'single species' approach to conservation can be ineffective and even counter-productive. For example, protecting cod could lead to increased fishing pressure on other predatory fish which then, by the mechanism we have demonstrated here, could lead to further negative effects on the cod."

The experiment was designed by a team of University of Exeter scientists and second-year undergraduate students. The idea came about during a seminar, in which students were challenged to design an experiment that could prove the theory that predators have indirect effects on each other. The students were so inspired by the idea of proving a long-held theory that more than 30 of them volunteered to conduct the experiment with their lecturers.


Story Source:

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


Cite This Page:

University of Exeter. "Study demonstrates that one extinction leads to another." ScienceDaily. ScienceDaily, 14 August 2012. <www.sciencedaily.com/releases/2012/08/120814213500.htm>.
University of Exeter. (2012, August 14). Study demonstrates that one extinction leads to another. ScienceDaily. Retrieved September 15, 2014 from www.sciencedaily.com/releases/2012/08/120814213500.htm
University of Exeter. "Study demonstrates that one extinction leads to another." ScienceDaily. www.sciencedaily.com/releases/2012/08/120814213500.htm (accessed September 15, 2014).

Share This



More Plants & Animals News

Monday, September 15, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Conservationists Face Uphill PR Battle With New Shark Rules

Conservationists Face Uphill PR Battle With New Shark Rules

Newsy (Sep. 14, 2014) — New conservation measures for shark fishing face an uphill PR battle in the fight to slow shark extinction. Video provided by Newsy
Powered by NewsLook.com
Shocker: Journalists Are Utterly Addicted To Coffee

Shocker: Journalists Are Utterly Addicted To Coffee

Newsy (Sep. 13, 2014) — A U.K. survey found that journalists consumed the most amount of coffee, but that's only the tip of the coffee-related statistics iceberg. Video provided by Newsy
Powered by NewsLook.com
'Magic Mushrooms' Could Help Smokers Quit

'Magic Mushrooms' Could Help Smokers Quit

Newsy (Sep. 11, 2014) — In a small study, researchers found that the majority of long-time smokers quit after taking psilocybin pills and undergoing therapy sessions. Video provided by Newsy
Powered by NewsLook.com
Spinosaurus Could Be First Semi-Aquatic Dinosaur

Spinosaurus Could Be First Semi-Aquatic Dinosaur

Newsy (Sep. 11, 2014) — New research has shown that the Spinosaurus, the largest carnivorous dinosaur, might have been just as well suited for life in the water as on land. Video provided by Newsy
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