Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

American carnivores evolved to avoid each other, new study suggests

11.03.2009
How do the many carnivorous animals of the Americas avoid competing for the same lunch, or becoming each other's meal?

A possible answer comes from a new study by a pair of researchers at the University of California, Davis.

Their large-scale analysis shows that it's not just chance that's at play, but avoidance strategies themselves that have been a driving force in the evolution of many carnivores, influencing such factors as whether species are active daytime or nighttime, whether they inhabit forests or grasslands, or live in trees or on the ground.

The Americas are home to more than 80 species of terrestrial carnivores, including cats, dogs, bears, weasels, skunks and raccoons. Commonly, 20 or more species can occupy the same region.

"For the most part, these overlapping species all share the same prey base -- other animals -- which includes each other," said Jennifer Hunter, who conducted the study for her Ph.D. dissertation in ecology.

Hunter and co-author Tim Caro, professor of wildlife, fish and conservation biology, first plotted the known ranges of all of the American carnivores on one big digital map. Assuming that wherever ranges overlapped, competition and predation between those species was possible, they then compared those animals' behavioral characteristics, body sizes and coloration. By analyzing this huge matrix of information, they were able to tease out broad patterns of strategies employed by each family.

For example, their map showed that the bear and dog families shared ranges with the greatest number of potential competitors. Most species in these families are omnivores, which helps reduce competition for a meat diet.

Raccoon family members, although small, run the lowest risk of becoming prey, because most live out of harm's way in trees.

One of their most surprising findings, Hunter said, was that the most petite carnivores, skunks, along with some weasels, lack an avoidance strategy. "When you look at all these overlays of ecology, these guys share all the same space at the same time with other carnivores."

How do these animals manage to survive? All skunks and a number of weasel species in this exposed group have facial or body coloring with an abrupt demarcation between white and dark. For skunks, this contrasting coloration almost surely warns predators of their noxious spray, Hunter explained, while with some weasel family members -- the notoriously aggressive badgers and wolverines, for example -- it may warn of ferocity.

The work provides a body of evidence for why these behaviors have evolved that could not have been obtained in the field, Hunter said.

Liese Greensfelder | EurekAlert!
Further information:
http://www.ucdavis.edu

More articles from Ecology, The Environment and Conservation:

nachricht Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

World’s oldest known oxygen oasis discovered

18.01.2018 | Earth Sciences

Uncovering decades of questionable investments

18.01.2018 | Business and Finance

Novel chip-based gene expression tool analyzes RNA quickly and accurately

18.01.2018 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>