Tag Archives: snakes

Family tree of all snakes and lizards

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This video is called The Beauty of Snakes (Animal Planet Documentary).

From George Washington University in the USA:

Biologist Maps the Family Tree of All Known Snake and Lizard Groups

A George Washington University biologist and a team of researchers have created the first large-scale evolutionary family tree for every snake and lizard around the globe.

The findings were recently published in the journal BMC Evolutionary Biology. Alex Pyron, the Robert F. Griggs Assistant Professor of Biology in GW’s Columbian College of Arts and Sciences, along with researchers from the City University of New York and Arizona State University, detail the cataloging of 4,161 species of snakes and lizards, or squamates.

“Squamates include all lizards and snakes found throughout the globe, including around 9,500 species on every continent except Antarctica, and found in most oceans,” said Dr. Pyron. “This is everything from cobras to garter snakes to tiny geckos to the Komodo Dragon to the Gila Monster. They range from tiny threadsnakes that can curl up on a dime to 10 feet monitor lizards and 30 foot pythons. They eat everything from ants to wildebeest.”

The evolutionary family tree, or phylogeny, includes all families and subfamilies and most genus and species groups, said Dr. Pyron. While there are gaps on some branches of the tree, the structure of the tree goes a long way toward fully mapping every genus and species group.

“It’s like building an incomplete family tree for your family, but with half of the ‘children’ sampled. You’re in it, but not your brother, one of your cousins is, but not another. However, because it’s so complete, we know where the missing relatives go because there’s no longer as much mystery as to how the missing species, or cousins, are related, with a few notable exceptions for some remaining species.

“This is also a community effort. We sequenced hundreds of these species ourselves but took thousands more from public databases, building on the work of others.”

Understanding how various snakes and lizards are connected to each other fills a major gap in knowledge, said Dr. Pyron, because before this, there were no single reference for how all lizards and snakes were related or what their classification was.

“A phylogeny and taxonomy is fundamental for all fields of biology that use lizards and snakes, to understand how to classify the species being studied, to interpret biological patterns in terms of relatedness, and even at a more basic level, to count how many species are in an area, for example, for conservation management purposes.”

This project has been in the works since 2008 with the last five years being the most intense. It was funded by the National Science Foundation Postdoctoral Research Fellowship in Biological Informatics.

The researchers used DNA sequencing technology to genotype, or identify, the DNA of thousands of lizards and snakes.

“We have laid down the structure of squamate relationships and yet this is still the beginning,” said Dr. Pyron. “As hundreds of new species are described every year from around the glove, this estimate of the squamate tree of life shows us what we do know, and more importantly, what we don’t know, and will hopefully spur even more research on the amazing diversity of lizards and snakes.”

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New snake discovery in Sri Lanka

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This video says about itself:

Crocodile Hunter – Island of Snakes

Feb 12, 2012

Steve Irwin travels to Sri Lanka to help laborers contend with some of the most venomous snakes in the world. And, for the first time in his life, he goes head-to-head with a man-eating Mugger crocodile.

All rights belong to Discovery Communications, Inc.

This video says about itself:

Thailand Blind Snake Not Poisonous. Smallest Snake in World?

These are super small snakes from Thailand. I found 2 in my restroom. They climb up through the drain from outside. I lost one of these small black snakes in the house – don’t tell “da wife”.

The name of this snake: Brahminy Blind Snake

Very common in Thailand. In just about every potted plant we have it seems like, as well as climbing up through our drains. They eat termite and ant eggs primarily. They can’t bite you – their mouths are too small. They live in the dark – inside the soil – just like a worm, but not worms.

Google “Ramphotyphlops braminus” the technical name, and check out the Wikipedia entry. Looks a lot like this one – right?

From Wildlife Extra:

New genus of snake recognised on Sri Lanka

Sri Lanka is a much bigger hotspot for biodiversity than previously known

March 2013. An assistant biology professor from George Washington University has discovered a new genus of the blindsnake in Sri Lanka.

Using DNA sequencing to determine its relationship to other snakes, Dr. Pyron thought the blindsnake -found right in the yard of an environmental agency office-would be a new species. Amazingly it turned out to be a complete new genus.

“When we sequenced the snake’s DNA, we discovered that it was an entirely new lineage of blindsnake,” Dr. Pyron said. “It’s still a blindsnake, but a new genus, a group of blindsnakes that had never been described.”

60 known species of snakes in Sri Lanka

Along with the discovery of the new group, Dr. Pyron and researchers confirmed the identity of 60 known species of snakes in Sri Lanka, using DNA sequencing technology on 40 of them to help researchers understand how various snakes are related to each other and their evolutionary relationship to other species around the world.

“We found that Sri Lanka has been colonized by snakes at least five times by totally different snake groups, which have each diversified heavily within the island,” said Dr. Pyron, a Robert F. Griggs Assistant Professor of Biology.

That means that even though researchers know a lot about the snakes on the island, there’s still more to be discovered-and previous research to be corrected.

Sri Lanka is a much bigger hotspot for biodiversity than previously known

“The DNA data are telling us new stories about how they are related, completely contradicting what we thought we knew,” he said. “It tells us that Sri Lanka is a much bigger hotspot for biodiversity than previously known, and harbours massive richness.”

Researchers can also use the findings to draw conclusions about evolutionary biology and species diversity more broadly.

Their findings, which appear in the March edition of the journal Molecular Phylogenetics and Evolution, show just how rich snake biodiversity is on the island.

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Chinese Year of the Snake, English adders

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This video is called Happy Chinese New Year of the Snake 2013.

This video about adders says about itself:

Vipera berus (huggorm) is the only venomous snake in Norway! I have made a video about this facinating creature. Too many people are killing them as soon as they see one. Maybe I can help change some minds?? Filmed in Ølen and Etne, Norway!

By Peter Frost in Britain:

The legless neighbours who mean no trouble

Thursday 07 February 2013

I always try to get up to the north Norfolk coast in winter. If you are lucky enough to get one of those crisp bright winter days as we did a week or so ago then there is no finer place on earth to blow away the winter cobwebs.

You will share the coast with thousands of winter birds and a few real surprise visitors and rarities.

My biggest, however, wasn’t a bird. It was snakes – more than I have ever seen at this time of year.

Adders are often spotted surprisingly early in the year. They are often seen in January or February on sunny days when the winter sun warms patches on the sandy paths and the adders emerge from their winter hibernation to bask.

My wife Ann pointed out 2013 is the Chinese year of the snake and suggested that was why there were so many this winter.

The adder is our commonest snake and sadly our most misunderstood – it is the only native venomous snake in Britain.

Adult males are rarely over two feet long, females might be a few inches longer but reports of adder sightings will often claim they are twice this long. Five and six foot claims are not unknown.

Most adders are distinctively marked with a dark zigzag running down the length of the spine and an inverted “V” shape on the neck.

Males are generally white or pale grey with a black zigzag. Females are a pale brown colour, with a darker brown zigzag.

A few are entirely black and are sometimes mistaken for exotic escaped snakes.

Adders are not aggressive animals. They will only bite as a last means of defence, usually if caught, cornered or trodden on.

No-one has died from adder bite in Britain for over 20 years. Only 14 deaths in the last century – 50 times more people die from bee and wasp stings.

With proper treatment, the worst effects of an adder bite are nausea and drowsiness followed by nasty swelling and bruising in the area of the bite.

Most people who are bitten were picking up the snake. Treat adders with respect, leave them alone, admire them from a distance and they will do you no harm.

The best time to see them is in early spring as they emerge from their hibernation dens.

Come April, the males will have shed their dull winter skin and are keen to mate – they rush about looking for females and occasionally wrestling with rival males.

The snakes writhe around each other in an impressive way, often covering the ground at great speed.

This behaviour was called the “dance of the adders” and was reckoned to be a mating ritual between a male and a female. We know better now.

Following mating, females seek out a suitable place to give birth, often travelling half a mile or more. Live births take place in late August to early September.

Adders do not lay eggs – young snakes are born live, a few inches long, perfectly formed miniature snakes.

During the autumn, adult snakes follow scent trails back to the hibernation site. Knots of snakes gather in sites they have used for years.

Adders usually eat small rodents – such as voles – lizards, frogs, newts, and occasionally young birds.

A full size adult will eat very little, perhaps no more than a dozen voles in a year.

Like all snakes, adders eat their prey whole. Flexible jaw bones and ribs mean they are able to swallow large prey whole.

Young adders are threatened by a variety of predators, including birds of prey – some are eaten by adult snakes. Others may be killed and eaten by rats or killed by cold while in hibernation.

They are protected by law against being killed, injured or disturbed – still every year many are killed by unthinking people.

Please don’t be one of them. Adders are a handsome addition to our countryside, especially in the Year of the Snake.

Chinese New Year in England: here.

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New Mozambique snake discovery

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Thelotornis usambaricus

From the Mozambique News Agency:

Mozambique: New Venomous Snake Discovered in Cabo Delgado

15 January 2013

Maputo — A researcher at Lurio University, based in the northern Mozambican province of Nampula, has discovered a species of highly venomous snake not previously known in the country.

The species is Thelotornis usambaricus, which belongs to a group of snakes commonly known as twig snakes. Previously, this species was only known from Tanzania, but the researcher, Harith Farooq, discovered it when he was undertaking a survey of terrestrial wild life on Vamizi island, in the Quirimbas archipelago, off the coast of Cabo Delgado province.

Farooq caught two of the snakes, which he could not immediately identify.

He sent one of the animals to the Natural History Museum in Zimbabwe to ascertain its taxonomic classification. This work was done by the zoologist Donald G. Broadley, who discovered the species in Tanzania in 2001.

The second of the snakes is now in the reptile collection kept in the branch of Lurio University in the Cabo Delgado provincial capital, Pemba.

Thelotornis Usambaricus is a member of the Thelotornis genus of back-fanged snakes. Its venom is hemotoxic – which means that it destroys red blood cells. This type of venom can disrupt blood clotting, and cause generalized tissue damage.

It is much slower acting than the neurotoxic venom (poison that affects the nervous system) of snakes such as the black mamba. However, no anti-venom has yet been developed for Thelotornis poison, and although bites are rare, fatalities have been recorded in Tanzania.

This snake usually conceals itself in trees, from which it strikes at its favoured prey – lizards, frogs and sometimes birds.

With this discovery, the number of snake species known to exist in Mozambique has risen to 96.

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American ratsnakes and climate change

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This video from the USA is called 6ft Black Rat Snake.

From ScienceDaily:

Global Warming Beneficial to Ratsnakes

Jan. 8, 2013 — Speculation about how animals will respond to climate change due to global warming led University of Illinois researcher Patrick Weatherhead and his students to conduct a study of ratsnakes at three different latitudes — Ontario, Illinois, and Texas. His findings suggest that ratsnakes will be able to adapt to the higher temperatures by becoming more active at night.

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Philippines endangered reptiles

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Philippine cobra

From the Philippine Star:

Phl cobra, 12 other reptiles on endangered list

By Michael Punongbayan

Updated December 31, 2012 – 12:00am

MANILA, Philippines – The Philippine cobra and 12 other reptiles have joined the country’s official list of threatened species, according to former senator Juan Miguel Zubiri.

Zubiri, former chairman of the Senate environment and natural resources committee and convenor of Pilipinas Ecowarriors, yesterday named the 12 other newly threatened reptiles as the Loggerhead turtle, Southeast Asian box turtle, Spiny terrapin, South-east Philippine spitting cobra (Naja samarensis), Equatorial spitting cobra, King cobra (Ophiophagus hannah), Southeast Asian softshell turtle, Batanes pit viper, Panay monitor lizard and three subspecies of the Malay monitor lizard.

The Philippine cobra was previously categorized only as near threatened but the snake’s decline in population led to the downgrading of its conservation status to threatened-endangered.

A highly venomous burly snake averaging a meter in length, the Philippine cobra (Naja philippinensis) thrives in low-lying plains, from thick jungles and forested areas to open fields and grasslands.

The reptile preys mostly on small rodents and frogs and occasionally, other snakes, lizards and birds. Its predators include humans, birds of prey, the king cobra, and the mongoose.

Zubiri said the species are tagged threatened once their habitats have suffered extreme depletion and their populations have fallen to a level below which the species or subspecies will be totally extinct.

He explained that threatened species are further sub-classified either as vulnerable, endangered, or critically endangered.

Zubiri said vulnerable species are under threat from serious adverse factors all over their range and are believed likely to drop to the endangered category in the near future.

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Colourful North American snakes, video

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This video from Canada says about itself:

Colorful Snakes: Appreciation Can Enhance Conservation

from The Sticky Tongue Project

“The great outdoors is the foundation of all life on Earth, including yours.” Episode 2 of a year-long 24 episode education-outreach video series starring Whit Gibbons (Herpetologist and Author), produced in cooperation with The Amphibian and Reptile Conservancy.

This series features “fascinating facts and helpful conservation tips” for everyone “from homeowners to professional land and wildlife managers.

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Obama lizard became extinct with dinosaurs

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Obamodon, Cretaceous lizards, snakes and dinosaurs

From e! Science News:

Asteroid that killed the dinosaurs also wiped out the ‘Obamadon’

Published: Monday, December 10, 2012 – 17:06 in Paleontology & Archaeology

The asteroid collision widely thought to have killed the dinosaurs also led to extreme devastation among snake and lizard species, according to new research — including the extinction of a newly identified lizard Yale and Harvard scientists have named Obamadon gracilis. “The asteroid event is typically thought of as affecting the dinosaurs primarily,” said Nicholas R. Longrich, a postdoctoral associate with Yale’s Department of Geology and Geophysics and lead author of the study. “But it basically cut this broad swath across the entire ecosystem, taking out everything. Snakes and lizards were hit extremely hard.”

The study was scheduled for online publication the week of Dec. 10 in the Proceedings of the National Academy of Sciences.

Earlier studies have suggested that some snake and lizard species (as well as many mammals, birds, insects and plants) became extinct after the asteroid struck Earth 65.5 million years ago, on the edge of the Yucatan Peninsula. But the new research argues that the collision’s consequences were far more serious for snakes and lizards than previously understood. As many as 83 percent of all snake and lizard species died off, the researchers said — and the bigger the creature, the more likely it was to become extinct, with no species larger than one pound surviving.

The results are based on a detailed examination of previously collected snake and lizard fossils covering a territory in western North America stretching from New Mexico in the southwestern United States to Alberta, Canada. The authors examined 21 previously known species and also identified nine new lizards and snakes.

They found that a remarkable range of reptile species lived in the last days of the dinosaurs. Some were tiny lizards. One snake was the size of a boa constrictor, large enough to take the eggs and young of many dinosaur species. Iguana-like plant-eating lizards inhabited the southwest, while carnivorous lizards hunted through the swamps and flood plains of what is now Montana, some of them up to six feet long.

“Lizards and snakes rivaled the dinosaurs in terms of diversity, making it just as much an ‘Age of Lizards’ as an ‘Age of Dinosaurs,’” Longrich said.

The scientists then conducted a detailed analysis of the relationships of these reptiles, showing that many represented archaic lizard and snake families that disappeared at the end of the Cretaceous, following the asteroid strike.

One of the most diverse lizard branches wiped out was the Polyglyphanodontia. This broad category of lizards included up to 40 percent of all lizards then living in North America, according to the researchers. In reassessing previously collected fossils, they came across an unnamed species and called it Obamadon gracilis. In Latin, odon means “tooth” and gracilis means “slender.”

“It is a small polyglyphanodontian distinguished by tall, slender teeth with large central cusps separated from small accessory cusps by lingual grooves,” the researchers write of Obamadon, which is known primarily from the jaw bones of two specimens. Longrich said the creature likely measured less than one foot long and probably ate insects.

He said no one should impute any political significance to the decision to name the extinct lizard after the recently re-elected U.S. president: “We’re just having fun with taxonomy.”

The mass (but not total) extinction of snakes and lizards paved the way for the evolution and diversification of the survivors by eliminating competitors, the researchers said. There are about 9,000 species of lizard and snake alive today. “They didn’t win because they were better adapted, they basically won by default, because all their competitors were eliminated,” Longrich said.

Co-author Bhart-Anjan S. Bhullar, a doctoral student in organismic and evolutionary biology at Harvard University, said: “One of the most important innovations in this work is that we were able to precisely reconstruct the relationships of extinct reptiles from very fragmentary jaw material. This had tacitly been thought impossible for creatures other than mammals. Our study then becomes the pilot for a wave of inquiry using neglected fossils and underscores the importance of museums like the Yale Peabody as archives of primary data on evolution — data that yield richer insights with each new era of scientific investigation.”

Jacques A. Gauthier, professor of geology and geophysics at Yale and curator of vertebrate paleontology and vertebrate zoology, is also an author.

The paper is titled “Mass Extinction of Lizards and Snakes at the Cretaceous-Paleogene Boundary.” The National Science Foundation and the Yale Institute for Biospheric Studies supported the research.

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Saving Canadian turtles’ lives

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The Sticky Tongue Project in Canada writes about this video:

New Video: Reptile Fencing: Reducing Road Mortality

Long Point Provincial Park (Ontario, Canada) is home to 19 species of turtles and snakes, of which 12 are listed as being Species at Risk. These reptiles frequently cross the road or bask on it for warmth within the park. Unfortunately, this puts them in danger and many are killed. The Long Point Basin Land Trust and Long Point Provincial Park worked together to make the park safer for these animals.

Reptile fencing has been installed in priority areas (750 meters on both sides of the road) where the highest levels of mortality were recorded. The fencing acts as a physical barrier to prevent reptiles from moving onto the roads and potentially being struck by vehicles.

Since the park is closed and vehicle entry is blocked for much of the year, park staff are able to create openings to let animals through from October through until May each year to allow seasonal movements. They are also exploring the possibility of creating a more permanent solution which could include underpasses.

Another very successful wildlife barrier, complete with underpasses has also been installed at Big Creek Mark by the Long Point Causeway Improvement Project. The installation of a third culvert is now underway.

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