Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

African Rodent Uses “Poison Arrow” Toxin to Deter Predators

05.08.2011
Woe to the clueless predator trying to make a meal of the African crested rat, a rodent that applies poisonous plant toxin to sponge-like hairs on its flanks, a discovery recently made by Jonathan Kingdon and colleagues from the National Museums of Kenya, the Wildlife Conservation Society, and University of Oxford.

In the only known instance of a mammal acquiring a lethal toxin from a plant for defense, the researchers have discovered where the African crested rat (or maned rat) gets its poison: the Acokanthera tree, the same source used by East African hunters for poison arrows.

The study appears online in the Proceedings of The Royal Society B. The authors include: Jonathan Kingdon, Chris Holland, Tom Gheysens, Maxime Boulet-Audet, and Fritz Vollrath of the University of Oxford; Bernard Agwanda of the National Museums of Kenya; and Margaret Kinnaird and Tim O’Brien of the Wildlife Conservation Society.

“The African crested rat is a fascinating example of how a species can evolve a unique set of defenses in response to pressure from predators,” said Dr. Tim O’Brien, Senior Scientist of the Wildlife Conservation Society and a co-author on the study. “The animal and its acquired toxicity is unique among placental mammals.”

Scientists have long suspected that the African crested rat is poisonous, primarily due to the animal’s specialized behavior, such as exposing a black-and-white coloration on its flanks when threatened by predators, and accounts of dogs becoming ill or dying after encounters with rats. The new discovery concerns the nature of the chemical defense. Instead of producing poison itself—as is the case with poisonous mammals such as the duck-billed platypus and solenodon—the African crested rat finds its toxin (called ouabain) in tree bark.

The researchers confirmed the hypothesis by presenting a wild-caught rat with branches and roots of the Acokanthera tree. The rodent proceeded to gnaw and masticate the bark (avoiding the leaves and fruit) and apply the “slaver” on its flanks. Further, the research team employed electron microscopes to examine the unique structure of the flank hairs. In doing so, they found that the perforated cylindrical structure of the hairs facilitates the rapid absorption of the poisonous saliva. Interestingly, ouabain has also been used by doctors for centuries as a clinical treatment against congestive heart failure.

Besides its warning coloration and poisonous hairs, the African crested rat possesses a thick reinforced skull, thick vertebrae, and unusually tough skin, all protection for the small rodent that rarely grows to more than 2 pounds in weight.

Several mysteries about the enigmatic rodent remain, including how the animal uses poison without succumbing to it.

John Delaney | Newswise Science News
Further information:
http://www.wcs.org

More articles from Ecology, The Environment and Conservation:

nachricht Global threat to primates concerns us all
19.01.2017 | Deutsches Primatenzentrum GmbH - Leibniz-Institut für Primatenforschung

nachricht Reducing household waste with less energy
18.01.2017 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

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: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>