Smallest chameleons have fastest tongues, new research


This 4 January 2016 video is about the smallest chameleon species, like the thumb-sized rosette-nosed chameleon, having the fastest tongues.

From Brown University in the USA about this today:

Tiniest chameleons deliver most powerful tongue-lashings

January 4, 2016

A new study reports one of the most explosive movements in the animal kingdom: the mighty tongue acceleration of a chameleon just a couple of inches long. The research illustrates that to observe some of nature’s best performances, scientists sometimes have to look at its littlest species.

PROVIDENCE, R.I. [Brown University] — Chameleons are known for sticking their tongues out at the world fast and far, but until a new study by Brown University biologist Christopher Anderson, the true extent of this awesome capability had been largely overlooked. That’s because the smallest species hadn’t been measured.

“Smaller species have higher performance than larger species,” said Anderson, a postdoctoral research associate in the Department of Ecology and Evolutionary Biology.

In Scientific Reports, Anderson reports that ballistic tongue projection in a chameleon that would fit on your thumb produced a peak acceleration 264 times greater than the acceleration due to gravity. In automotive terms, the tongue could go from 0 to 60 miles per hour in a hundredth of a second, though it only needs about 20 milliseconds to snag a cricket.

Anderson’s review of the biomechanics literature suggests that the motion has the highest acceleration and power output produced per kilogram of muscle mass by any reptile, bird, or mammal and is the second most powerful among any kind of vertebrate (only a salamander outdoes it). The total power output of the plucky Rhampholeon spinosus chameleon’s tongue was 14,040 watts per kilogram.

The secret of chameleons is that they don’t just use spontaneous muscle power to fling their tongues. They preload most of the motion’s total energy into elastic tissues in their tongue. The recoil of those tissues greatly augments what muscle alone can do on the fly — to catch a fly.

Anderson wanted to find the upper limit of chameleon tongue performance. To do that, he gathered individuals of 20 species of widely varying sizes in his former University of South Florida lab. Then he perched them one by one in front of a camera that shoots 3,000 frames a second. For each measurement, a cricket hung off a small dangling mesh to tempt the tongue to emerge. When it did, he could measure the distance the tongue went, the elapsed time, and the speed and the acceleration at any given time.

What Anderson noticed across all his measurements and analysis was that the smaller the chameleon, the higher the peak acceleration, relative power, and distance of tongue extension relative to body size (Rhampholeon spinosus stuck out its tongue to 2.5 times its body length). Larger chameleons produced impressive motions, too, but not compared to their smaller cousins. For example, a roughly two-foot-long species, Furcifer oustaleti, managed a peak acceleration less than 18 percent that of the tiny champ, Rhamp.

The results make physical and evolutionary sense, Anderson said. All of the chameleons have the same catapult-like apparatus for launching the tongue, but proportional to their size, smaller chameleons have a bigger one than larger chameleons. They are like little sports cars with relatively powerful engines.

The evolutionary reason why tiny chameleons are proportionately better equipped for feeding is presumed to be because, like all small animals, they need to consume more energy per body weight to survive. So little chameleons must be especially good at catching their insect meals — their tongues have to burst out unusually fast and far to compete for all that needed nutrition.

For these reasons, Anderson said, it will often benefit researchers to look at the little guys when studying physical performance. Prior studies of chameleon tongue acceleration had measured much lower peak values because they only looked at much larger chameleons.

“What this study shows is that by using smaller species, we may be able to elucidate these higher performance values,” he said.

Amphibian, reptile films at Rotterdam festival


This video says about itself:

Adapting Anolis

Short wildlife film documenting the adaptations of Cuba’s Anolis lizards that have allowed them to dominate Cuba‘s jungles.

At the Wildlife Film Festival in Rotterdam, the Netherlands, there are not only films about birds and mammals, but also the film Adapting Anolis.

The festival organisers write about it:

Cuba’s rainforests are famous for housing the Anolis lizard. There are over 60 different species of Anolis lizard living in Cuba ranging in size from minute to mighty. These lizards have managed to dominate Cuba’s jungle and Adapting Anolis explores the adaptions that have allowed these lizards to become so successful.

There is also the film Pyrenees Island, about a newly discovered amphibian species.

The festival organisers write about it:

In 1990, the discovery of a mysterious frog motivated a Spanish ecologist to begin research on this little amphibian. After three years of extensive studies, Jordi Serra Cobo finally described this new species and named it Rana pyrenaica. Starting in the footsteps of the rare Pyrenean frog, the film invites us into the chaotic world of high mountain torrents.

In this turbulent environment, strange rare beings live alongside the frog. All of them have a complex evolutionary history. All of them are now threatened with extinction. The story tells us not only about the magic of the Pyrenean frog the naturalist discovered, but it also has a lot to teach us about ourselves and the uncertain future that awaits us.

And there is also this Dutch film about frogs at the festival.

Greek lizards and food shortages, new research


This video is about freeing two Balkan green lizards.

From Wildlife Extra:

Greek lizards change their digestive tracts to cope with food shortages

With little to eat on many Greek islands, Balkan green lizards have evolved their digestive systems considerably compared to members of the same species on the mainland.

Even more surprisingly, these insect-eating lizards have also developed special valves to help them to digest plants.

These facts have emerged from a study led by Konstantinos Sagonas of the National and Kapodistrian University of Athens in Greece and published in Springer’s journal The Science of Nature.

The new study confirms how some reptiles can adjust their digestive system and food preferences in response to adverse circumstances such as low rainfall and poor food supply.

Previous studies have shown that insect-eating Balkan green lizards (Lacerta trilineata) surviving in the harsh environments of various Greek islands have broadened their diet to include more plants.

To extend this research, Sagonas’ team set out to compare groups of these lizards on the islands of Andros and Skyros with two other populations in mainland Greece.

They found that the island lizards have a longer small intestine and hindgut compared to their mainland counterparts.

Those collected from the island of Skyros also have longer stomachs.

Cecal valves, which slow down food passage and provide fermenting chambers, were found in 62 per cent of the island-dwelling lizards, compared to 19 per cent of the mainland ones. This was a fact not previously known for green lizards.

Cecal valves are typically found in plant-eating lizards, and host micro-organisms that help to ferment and break down plant material into fatty acids.

When these structures do occur in insect-eating lizards, it is generally among populations that have started to eat a varied diet that also includes plants.

Sagonas believes the presence of cecal valves among the island lizards therefore reflects their higher consumption of plant material.

About 30 per cent of their diet consists of plant material, compared to the 10 per cent of the mainland reptiles.

So because of their longer digestive tract and the presence of cecal valves, it takes up to 26 per cent longer for the food of island lizards to pass through their digestive system and the ingested food is exposed for far longer to digestive enzymes.

“Such adaptations allow insular populations to take advantage of the limited food resources of the islands and, eventually, overcome food dearth,” explains Sagonas.

“Energy flow in insular environments, the digestive performance of insular populations and the connections within them, provide insights into how animals are able to colonise islands and maintain viable populations.”

Unlike Greek lizards, Greek humans cannot adapt their digestive systems to the hunger, caused by the European UnionIMF imposition of ‘austerity‘.

Reptiles and amphibians in the botanical garden


Eastern collared lizard, 7 September 2015

This photo shows an eastern collared lizard, a species originally from North America. We saw this individual on 7 September 2015, at the big AquaHortus exhibition of aquariums and terrariums. Again, all photos in this blog post are macro lens photos.

There were quite some frogs in the terrariums in the botanical garden entrance building, including Dendrobates tinctorius, and Lepidobatrachus laevis.

Eastern collared lizard, on 7 September 2015

One story higher was a terrarium with three eastern collared lizards.

And a terrarium with a central bearded dragon from Australia.

Indian star tortoise, 7 September 2015

We continued to a hothouse. Near the entrance, a terrarium with this young Indian star tortoise.

Nearby, some relatives: Hermann’s tortoise; European pond turtle; red-bellied short-necked turtle; and leopard tortoise.

Also in this hothouse, colourful amphibians. Including oriental fire-bellied toad.

And spot-legged poison frog. Not far from a panther chameleon terrarium.

Mission golden-eyed tree frog, 7 September 2015

Also, a terrarium with some Mission golden-eyed tree frogs.

Dutch Orchid Society terrarium

The Dutch Orchid Society had a terrarium of its own at the exhibition.

Poison dart frog, 7 September 2015

It contained not only various orchid species, but also a few poison dart frogs, like this one.

Stay tuned, as there will be another blog post, about botanical garden plants.

Slow worm discovery on Ameland island


This video says about itself:

20 April 2014

A baby female Adder Vipera berus berus is shown curling up alongside an adult male Slow-worm Anguis fragilis. The tiny snake would have been born during the previous year and it is just as venomous as an adult.

Translated from the press agency of Ameland island in the Netherlands:

Slow worm seen on Ameland

July 25, 2015

HOLLUM – This Saturday, Annelies Lap from Hollum village saw on the horse trail near the Duck Pond a slow worm. She immediately photographed it.

It is a remarkable observation, because slow worms do not live on the Wadden Sea islands. In 2014 one was reported in a garden on Texel island. Ecomare museum on Texel suspects the animal lifted to the island, eg it made the sea crossing with compost or straw. Probably also the Ameland individual arrived like this as a stowaway on the island.

Lesser Antillean iguana research on St Eustatius island


This video shows a Lesser Antillean iguana, on Ilet Chancel – Martinique, in the Caribbean.

Translated from the Dutch RAVON herpetologists:

Wednesday, July 15, 2015

Population research on the endangered Lesser Antillean Iguana on the Dutch Caribbean island of St. Eustatius is in full swing. From April to June, 60% of the island was scoured and 212 iguanas were observed, of which 160 animals are now individually identified and participate in scientific research. This research is an important part of the conservation plan which was launched in September 2014 by St. Eustatius National Parks (STENAPA) and RAVON.

Helping Dutch wall lizards


This is a wall lizard video from Switzerland.

Wall lizards are very rare in the Netherlands. They only live at old military forts around Maastricht city.

‘Development’ plans in Maastricht threaten the animals.

However, the Dutch RAVON herpetologists have managed to change the plans in ways favourable to the Maastricht wall lizards.

The Belvédèreberg hill, formerly a landfill, has been reconstructed for the wall lizards and slow worms.

Also, wildlife tunnels will be built to help the reptiles.