Florida green anoles adapt to invasive species


This video from the USA says about itself:

The largest Green Anole ever!

The Carolina anole (Anolis carolinensis) is an arboreal lizard found primarily in the southeastern United States and some Caribbean islands. Other common names include the green anole, American anole and red-throated anole. It is also sometimes referred to as the American chameleon due to its ability to change color from several brown hues to bright green. While many kinds of lizards are capable of changing color, anoles are closely related to iguanas and are not true chameleons. The Carolina is a small lizard; male adults are usually 15 cm (5.9 in) long in adulthood, about half of which is its tail, and it can weigh from 3–7 g (0.11–0.25 oz). Exceptionally, these anoles will grow up to 20 cm (7.9 in) in length.

From Breaking News:

A lizard species in Florida has evolved very quickly to deal with invaders

24/10/2014 – 12:16:32

In as little as 15 years, lizards native to Florida – known as Carolina anoles or green anoles – have adapted to deal with the threat of an invading species of lizard, Cuban or brown anoles.

This video is called Egg-laying brown anole (Anolis sagrei), Aruba. This female brown anole was filmed during digging a hole in the sand in which she layed an egg.

After having contact with the invasive species, said to have first gone to America from Cuba in the 1950s, the native lizards starting perching higher up in trees. Over the course of 15 years and 20 generations, their feet evolved to become better at gripping the thinner, smoother branches found higher up.

The change was rapid. After a few months the native lizards started moving higher up the branches and over 15 years, their toe pads had become larger with stickier scales on their feet.

“We did predict that we’d see a change, but the degree and quickness with which they evolved was surprising,” said Yoel Stuart, a post-doctoral researcher in the College of Natural Sciences at The University of Texas at Austin and lead author of the study.

“To put this shift in perspective, if human height were evolving as fast as these lizards’ toes, the height of an average American man would increase from about 5 foot 9 inches today to about 6 foot 4 inches within 20 generations — an increase that would make the average U.S. male the height of an NBA shooting guard,” said Stuart. “Although humans live longer than lizards, this rate of change would still be rapid in evolutionary terms.”

This latest study is one of only a few well-documented examples of what evolutionary biologists call “character displacement,” where similar species competing with each other evolve differences to take advantage of different ecological niches.

A classic example comes from the finches studied by Charles Darwin. Two species of finch in the Galapagos Islands diverged in beak shape as they adapted to different food sources.

The researchers speculate that the competition between brown and green anoles for the same food and space may be driving the adaptations of the green anoles. Stuart also noted that the adults of both species are known to eat the hatchlings of the other species.

“So it may be that if you’re a hatchling, you need to move up into the trees quickly or you’ll get eaten,” said Stuart. “Maybe if you have bigger toe pads, you’ll do that better than if you don’t.”

The research was published in the journal Science.

See also here. And here. And here.

Young common lizard, video


This is a video about a common lizard in the Netherlands.

Its dark tail shows that this is still a really young animal.

Robin Jongerden made the video.

Lizards in Saudi Arabia


This video is called Reptile Classification Project – Biology.

In Saudi Arabia, there is not just lots of oil, an absolute monarchy and courageous human rights activists, but also wildlife.

By John M. Regan:

Herping The Kingdom of Saudi Arabia

Imagine a land with lizards so large and numerous that you can spot them from a speeding car as they pop up from their burrows. A country where lizards are so prevalent that they scatter away from your approaching footsteps like a school of lakeside minnows. If this tickles your lacertilian fancy, then you owe it to yourself to visit Saudi Arabia, a place where lizards rule.

If only that would be literally true; then, there would not be those beheadings.

Herping the Kingdom of Saudi Arabia

The largest country in the Middle East, the Kingdom of Saudi Arabia is a huge chunk of desert about one-fifth the size of the United States. It is bordered on the north by Iraq and Iran; Yemen and Oman round out its southern tip. To the east and west sit the strategic waterways of the Persian Gulf and the Red Sea. Ruled by King Abdullah, son of the first Saudi king, Saudi Arabia is truly a monarchy. The country is a predominately harsh desert with no running waterways or large permanent bodies of water. Summer temperatures regularly exceed 120 degrees Fahrenheit, and barely 2 percent of the country is arable. Yet with 20 percent of the world’s proven oil reserves, it is a country of enormous geopolitical and economic importance.

There are at least 100 lizard species in Saudi Arabia, many perhaps unknown in the west. The Saudis are not known as great naturalists, and species identification is a challenge. Geckos of almost pure white emerge at night, and big pot-bellied geckos haunt wadi caves. Large desert monitors prowl the land as well. For any reptile enthusiast, Saudi Arabia is a potential treasure trove. …

For sightseeing and herping in the Riyadh area, two locations are in the absolute must-see category: Thumamah and the Tuwayq Mountains. Thumamah is a Saudi national park that is an intriguing complex of cliffs, deep wadis and hidden valleys. In addition to being fertile herping grounds, Thumamah is a fossil hunter’s dream. Entire hillsides are comprised of the fossilized remains of coral, shells and sponges. Plush Bedouin-style tents are available for overnight stays. The Tuwayq Mountains, also known as the “Edge of the World,” is an astounding ridge of desert cliffs that stop abruptly and overlook a desert plain that seems to go on to infinity. …

The Riyadh Escarpment, a dramatic curving line of spectacular desert cliffs, runs from north to south along the west side of the city. The scenery is stunning and the fauna in the area is just as dazzling. A single day’s outing reveals everything from camel spiders to baboons. Wolves and hyenas prowl; owls, falcons and eagles soar. Reptiles abound.

The Lizards of Saudi Arabia

But lizards rule. Geckos colored from shades of pink to white run about inside and outside of homes, and they inhabit every crack and crevice of backyards by the dozens. In the desert, the supremacy of lizards is even more evident. In fact, the lizard population is so large that a dedicated observer can soon learn to gauge the temperature of the day simply by identifying the species of lizard that happens to be out at a particular time. It is as though the lizards have taken over the role of rodents in this austere climate.

Geckos and agamids boast the largest variety of species, with the nod toward sheer numbers going to the geckos. Agamids, however, hold the size title. The largest and most famous of the Saudi agamids is the Egyptian uromastyx (Uromastyx aegyptia), also known as the dhub. With an adult length of 2 feet and a hefty 7- to 10-pound weight, the Egyptian uromastyx is the largest lizard species in Saudi and the most well known. They have long been a favorite at the Saudi dinner table. Bedouin desert dwellers are experts at smoking the reptiles out of their den and making a snack out of the lizard’s tail.

Those countless years of hunting have made the Egyptian uromastyx a very wary animal. Despite their size and squat appearance, they are extraordinarily fast and race to their burrow at the first inkling of danger. Catching one in the open is not an easy task. Finding them, however, is hardly a challenge. As the morning heat rises to about 90 degrees — cool by Saudi standards — the Egyptian uromastyx begin to emerge. They are so large and their burrows so distinctive that they are easy to see even when you’re rolling along at a moderate speed in a car. Their resemblance to prairie dogs is remarkable. Like prairie dogs, they are plant eaters. These stout lizards normally exhibit a dull desert-beige color, but in the spring, females display their finery and show off a beautiful variation of vivid yellow-and-black mating colors.

Another large agamid is Agama blandfordi. Bearing a marked resemblance in color and body type to bearded lizards, A. blandfordi reaches 10 inches in length and is just as noticeable a part of the desert landscape as the Egyptian uromastyx. Yet unlike the easily spooked Egyptian uro, these agamids are extraordinarily approachable. Their distinctive profiles grace exposed rocks, dirt mounds and scrub brushes as they calmly bask during the hottest part of the desert day. Perhaps this is the key to their approachability — they simply aren’t used to seeing other living things stirring in this heat. Photographing an A. blandfordi is as easy as driving your vehicle up to its basking rock and clicking the shutter. They can be approached on foot just as easily.

Although A. blandfordi initially appears as a lizard-shaped extension of light-gray rock, a closer look reveals unique wavy patterns of long, dark bands that run the entire length of the animal’s body. At the base of the lizard’s tail, the stripes are interrupted by brown-gray bands. The legs and feet, right down to the animal’s claws, also display this classic camouflage strategy.

Egyptian uromastyx excepted, this nonchalance in the presence of humans seems to be the case with many of the agamid species in the area. The smaller and much prettier spotted toad-headed agama (Phrynocephalus maculatus) prefers rocky landscapes in more moderate heat. These slender lizards often sit very still and allow the photographer to belly crawl all around while snapping close-up after close-up.

On the other end of the size scale are a number of small, American-anole-shaped lizards that inhabit a variety of desert niches. The delicately designed Hadramaut sand lizard (Mesalina adramitana) stretches out to just 2 inches. This diminutive reptile is a marvelous example of adaptation to extreme conditions. They are most common in areas of small, pancake-shaped rocks devoid of vegetation or anything approaching moisture. No bigger than a medium-sized dragonfly, this little lizard comes out at nearly the height of midday heat. Fast and perfectly camouflaged in sandy beige, it is a difficult animal to spot. At first you think the heat and bland terrain are playing tricks on your eyes. Eventually you realize that those tiny, light-brown flickers in your peripheral vision are actually this small lizard. The obvious food source for the sand lizard is small insects, while there are several Saudi scorpions that will just as easily make a meal out of the sand lizard.

Good wall lizard news


This video is about counting wall lizards along the railroad to Lanaken in Belgium, near Maastricht in Limburg province in the Netherlands.

Translated from the Dutch RAVON herpetologists:

Wednesday, September 17th, 2014

During the renovation of a railway line in Maastricht in 2008 the wall lizard was taken into account. For those lizards, very rare in the Netherlands then there more than 20 drystone walls were built. Since then, the population is closely monitored annually by RAVON. This monitoring showed until recently that there was a slow recovery. However, the reproductive success was lower than people hoped. But the counts of this late summer bring good news. This year, more newborn wall lizards are crawling around than ever before!

Protecting vulnerable populations

The wall lizard lives in the Netherlands originally only in Maastricht. Here live a few hundred to under a thousand animals. That may seem like a lot, but on the northern edge of its range, in an isolated habitat this species in our country is very vulnerable.

Slow worm video


This is a video about a slow worm, in Balloërveld nature reserve in Drenthe province in the Netherlands.

Ben Ferwerda made the video.