Salamander's elastic tongue powered by 'coiled spring'

Salamanders' tongues release at very high speed no matter the temperature, but the cold does slow their tongues' retraction

Related Stories

Salamanders can snatch up prey in a few thousandths of a second - striking out with elastic tongues.

Scientists have now found that the amphibians, which depend on the ambient temperature to heat their muscles, maintain this strike speed in the cold.

But, as footage of the animals has revealed, low temperatures do slow the retraction of their deadly tongues.

The findings are reported in the Journal of Experimental Zoology.

Dr Stephen Deban from the University of South Florida had already studied this effect in other amphibians and reptiles.

"We previously found that tongue projection in toads and chameleons is independent - or nearly so - of temperature," Dr Deban told BBC Nature.

Start Quote

The tongue is launched by the elastic recoil”

End Quote Dr Stephen Deban University of South Florida

"We then turned to some older films we had of salamanders."

He and his colleague, Jason Richardson, focused on Hydromantes platycephalus, a salamander species that can shoot its tongue a distance of 80% of its body length in less than 20 thousandths of a second.

They filmed super slow-motion footage of the animals as they struck out at fly larvae on a platform in front of them.

The scientists wanted to know if, like in toads and chameleons, the muscles that powered the tongue's projection acted like a coiling spring - storing up energy then suddenly letting go and releasing the tongue at extremely high speed.

They studied the animals as they snatched up the larvae over a ranged of temperatures - from 2C to 24C. The salamanders projected their tongues just as quickly and just as far over the whole of this temperature range.

'Cold-blooded sniper'

Dr Deban likened the animals' tongue to an arrow being shot from a bow.

"In the salamanders, and toads and chameleons, the tongue is launched by the elastic recoil," Dr Deban said.

"When they're cold, they can still 'pull back the bow', but it takes longer. However this doesn't matter because the recoil still launches the tongue quickly."

But the muscle-powered process of retracting the tongue was significantly slower at lower temperatures.

The researchers described the salamanders as "cold-blooded snipers". Despite depending on the external temperature to warm their muscles, the amphibians are still able to outmanoeuvre their prey in the cold; elastic recoil seems to be the evolutionary trick allowing them to do this.

The scientists were keen to clarify the term "cold-blooded", which - although a familiar description used for many reptiles, amphibians and fish - can be misleading.

"Cold-blooded animals, like lizards, can actually reach very high body temperatures," Dr Deban explained. This is particularly true of desert-dwelling reptiles.

Animals whose body temperature is determined by their environment are known, in scientific terms, as ectothermic or poikilothermic.

More on This Story

Related Stories

The BBC is not responsible for the content of external Internet sites

More from nature

  • Cardinal fish and ostracodFish filmed spitting 'fireworks'

    Film crew captures ostracods' spectacular defensive lightshow that makes predatory fish spit them out.

  • Arapaima'Locally extinct'

    A giant fish which used to dominate the Amazon river is now absent in many areas

  • DragonflyRapid reactions

    Dragonfly's super quick reactions recorded in slow motion by BBC film-makers

  • Wingless adult male of the midge Belgica antarcticaExtreme survivor

    Antarctic midge's small genome may be an adaptation to its extreme environment

  • Myotis midastactus specimen (previously identified as Myotis simus)Golden discovery

    A bat from Bolivia is described as a new species by scientists

  • Dinosaurs 'shrank' to become birds

    Huge meat-eating, land-living dinosaurs evolved into birds by constantly shrinking for over 50 million years, new research shows.

  • Would we starve without bees?

    Honey bees are under threat, and as pollination significantly contributes to the food we eat, what would we do without them?

  • Eggshells may act like 'sunblock'

    Birds' eggs show adaptations in pigment concentration and thickness to allow the right amount of sun for embryos, scientists say.

  • Female shrimps are more aggressive

    Female snapping shrimps are more aggressive than males when defending their territories despite their smaller claw size, a study shows.

BBC iWonder

  • Honey bee close-upInsect intelligence

    Are honey bees as smart as your sat nav?

  • Tyrannosaurus rex skull (c) Mark Williamson / Science Photo LibraryDinosaur dynasty

    One group of dinosaurs survived and their descendants can be seen all around us today

  • Brown rat cluse upRise of the rodent

    Reports of giant, 'super rats' are filling the headlines. But why are we being overrun by rats?

  • Cuckoo portraitHoliday hotspot

    What makes the UK such an attractive destination for visiting wildlife?

There have been 75 solar eclipses and 167 major volcanic eruptions in my lifetime

Nicole Malliotakis on Twitter comments on the events that have happened since she was born by using our personalised Your Life on Earth interactive infographic.

Things To Do


More Nature Activities >

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.