Featured Research

from universities, journals, and other organizations

Lizard fossil provides missing link to show body shapes of snakes and limbless lizards evolved independently

Date:
May 19, 2011
Source:
University of Toronto
Summary:
The recent discovery of a tiny, 47 million-year-old fossil of a lizard called Cryptolacerta hassiaca provides the first anatomical evidence that the body shapes of snakes and limbless lizards evolved independently.

Image of the nearly complete fossil of Cryptolacerta hassiaca.
Credit: Image courtesy of University of Toronto

Until a recent discovery, theories about the origins and evolutionary relationships of snakes barely had a leg to stand on.

Genetic studies suggest that snakes are related to monitor lizards and iguanas, while their anatomy points to amphisbaenians ("worm lizards"), a group of burrowing lizards with snake-like bodies. The debate has been unresolved--until now. The recent discovery by researchers from the University of Toronto Mississauga and the Museum für Naturkunde Berlin, Germany of a tiny, 47 million-year-old fossil of a lizard called Cryptolacerta hassiaca provides the first anatomical evidence that the body shapes of snakes and limbless lizards evolved independently.

"This fossil refutes the theory that snakes and other burrowing reptiles share a common ancestry and reveals that their body shapes evolved independently," says lead author Professor Johannes Müller of Humboldt-Universität, Berlin.

The fossil reveals that amphisbaenians are not closely related to snakes, but instead are related to lacertids, a group of limbed lizards from Europe, Africa and Asia. "This is the sort of study that shows the unique contributions of fossils in understanding evolutionary relationships," says Professor Robert Reisz from the University of Toronto Mississauga, the senior author of the study. "It is particularly exciting to see that tiny fossil skeletons can answer some really important questions in vertebrate evolution."

The German research team, led by Müller and American graduate student Christy Hipsley, used X-ray computed tomography to reveal the detailed anatomy of the lizard's skull and combined the anatomy of Cryptolacerta and other lizards with DNA from living lizards and snakes to analyze relationships. Their results showed that Cryptolacerta shared a thickened, reinforced skull with worm lizards and that both were most closely related to lacertids, while snakes were related to monitor lizards like the living Komodo dragons.

Even though snakes and amphisbaeans separately evolved their elongate, limbless bodies, the discovery of Cryptolacerta reveals the early stages in the evolution of burrowing in lizards. By comparing Cryptolactera to living lizards with known lifestyles, co-author and U of T Mississauga paleontologist Jason Head determined that the animal likely inhabited leaf-litter environments and was an opportunistic burrower.

"Cryptolacerta shows us the early ecology of one of the most unique and specialized lizard groups, and also reveals the sequence of anatomical adaptations leading to amphisbaenians and their burrowing lifestyle," says Head. "Based on this discovery, it appears worm-lizards evolved head first."

The findings appear in the journal Nature.


Story Source:

The above story is based on materials provided by University of Toronto. Note: Materials may be edited for content and length.


Journal Reference:

  1. Johannes Müller, Christy A. Hipsley, Jason J. Head, Nikolay Kardjilov, André Hilger, Michael Wuttke, Robert R. Reisz. Eocene lizard from Germany reveals amphisbaenian origins. Nature, 2011; 473 (7347): 364 DOI: 10.1038/nature09919

Cite This Page:

University of Toronto. "Lizard fossil provides missing link to show body shapes of snakes and limbless lizards evolved independently." ScienceDaily. ScienceDaily, 19 May 2011. <www.sciencedaily.com/releases/2011/05/110518131416.htm>.
University of Toronto. (2011, May 19). Lizard fossil provides missing link to show body shapes of snakes and limbless lizards evolved independently. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2011/05/110518131416.htm
University of Toronto. "Lizard fossil provides missing link to show body shapes of snakes and limbless lizards evolved independently." ScienceDaily. www.sciencedaily.com/releases/2011/05/110518131416.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) — West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) — Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) — The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) — A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins