Lizard uses UV signals to ward off rivals

Mar 21, 2011 By Lyn Danninger

(PhysOrg.com) -- We’re all familiar with different animal species using a variety of strategies to attract a mate or chase off an aggressor or a rival. For birds, it’s often a dazzling display of plumage or a deafening vocalisation.

In other species, assuming an aggressive is a popular approach to marking a territory or keeping a rival at bay. But for the Augrabies flat lizard, which makes its home in , the approach is more subtle.

Male Augrabies flat lizards flash covert ultraviolet signals from a patch located on their throats to chase off their rivals. The use of colour patches to communicate social information is used by many animals, says Associate Professor Martin Whiting from Macquarie University, who led the study which was published earlier this month in the Proceedings of the Royal Society B.

Whiting and his team of researchers were able to confirm that the lizards have a high number of UV photoreceptors. This large number enhances their ability to determine their rival’s fighting ability because of their greater ability to discriminate between male throat colours. By being able to detect slight variations in UV-throat color, they can avoid potentially costly battles with rival males.

Previous studies on the lizard’s signalling behaviour have already shown that the throat patches of high quality males reflect a purer UV than those of weaker males, said Whiting, who works in the University’s Department of Biological Sciences in the Division of Brain, Behaviour and Evolution.

To determine if and how well the Augrabies flat lizard could see UV light, the researchers analysed electrical impulses in the lizard’s optic nerves when their retinas were triggered with lights of different colours. The result was compared with a similar species which had previously been studied. The Augrabies flat lizard was found to be three times more sensitive to UV than the similar species.

Why UV is favoured over other colors by some species, such as the Augrabies flat lizard, has been a source of great debate. One hypothesis is that UV has physical properties that make it a particularly sensitive indicator of male quality and therefore, allows animals to more accurately gauge the quality of a rival or potential mate. Augrabies flat seem to support this idea and may be the ideal system for further investigation of this fascinating channel of communication, Whiting said.

Explore further: Researchers collect soil samples from around the globe in effort to conduct fungi survey

Provided by Macquarie University

4.8 /5 (4 votes)

Related Stories

Fish can recognize a face based on UV pattern alone

Feb 25, 2010

Two species of damselfish may look identical -- not to mention drab -- to the human eye. But that's because, in comparison to the fish, all of us are essentially colorblind. A new study published online on ...

Lizards' feisty flicking changed by motion noise

Jul 05, 2007

Animals that alter their movement-based signals to overcome visually ‘noisy’ environments could lead to a better understanding of vision systems and improve the capacity of ‘seeing’ machines, according to scientists ...

Recommended for you

Male sex organ distinguishes 30 millipede species

19 hours ago

The unique shapes of male sex organs have helped describe thirty new millipede species from the Great Western Woodlands in the Goldfields, the largest area of relatively undisturbed Mediterranean climate ...

Dogs hear our words and how we say them

Nov 26, 2014

When people hear another person talking to them, they respond not only to what is being said—those consonants and vowels strung together into words and sentences—but also to other features of that speech—the ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.