Navigation Links
Unheard of life history for a vertebrate
Date:6/30/2008

There is a newly discovered life history among the 28,300 species of known tetrapods, or four-legged animals with backbones. A chameleon from arid southwestern Madagascar spends up to three-quarters of its life in an egg. Even more unusual, life after hatching is a mere 4 to 5 months. No other known four-legged animal has such a rapid growth rate and such a short life span. The new research is reported in the current issue of Proceedings of the National Academy of Sciences.

"It really is a huge surprise," says Christopher Raxworthy, Associate Curator in the Department of Herpetology at the American Museum of Natural History. "Adding to that, until now, the short life span of chameleons in captivity has always been considered as a failure to thrive. We need to rethink this."

Most mammals, reptiles, birds, and amphibians (all tetrapods) typically live 2 to 10 years, an average bracketed at the upper end by some long-lived animals (for example, turtles and humans that can live for a century) and at the lower end by a handful of animals that only live for about a year. The males in nine species of marsupials die off after a year, for example, as do most adults in about twelve species of lizards. But the chameleon described here, Furcifer labordi, not only has a brief, yearly life cycle, but the bulk of that time is spent incubating inside an egg. Once outside of the egg, all individuals in the population die within 4 to 5 months.

Kristopher Karsten, a graduate student from the Department of Zoology at Oklahoma State University, discovered the unusual life cycle almost by accident. "I showed up late in the season and found something weird," recalls Karsten. "There were no juveniles. But by February, I found carcasses all over with no signs of mutilation or predation. The population plummetedwe've never seen this with other lizards."

Now, after five seasons of data and sightings of nearly 400 individuals, the life cycle of F. labordi can be described. Hatching begins with the rains in November, and, once emerged, the chameleons develop rapidly, growing up to 2.6 mm (0.1 inches) a dayup to two orders of magnitude greater than other known lizard growth rate. In less than 60 days, for example, there can be a 300%-400% increase in body size for males to reach adulthood. After reaching maturity, the population reproduces, and females burrow through about 138 mm (5.4 inches) of sand to lay their eggs. Once covered, the eggs wait out the dry season for the next 8 to 9 months, and all adults die.

"It is amazing to think that for most of the year, this chameleon species is represented only by developing eggs buried in the ground," says Raxworthy. "This species really illustrates just how much there is still to discover about the natural history of Madagascar." Karsten agrees, adding: "We've identified a species that does something really different from the others, but what is driving this system? One bad year could wipe out these chameleons."


'/>"/>

Contact: Kristin Phillips
kphillips@amnh.org
212-496-3419
American Museum of Natural History
Source:Eurekalert  

Related biology news :

1. Geology and biology meet in the history of US southwestern desert surface waters
2. Smithsonian scientists find evidence that could rewrite Hawaiis botanical history
3. Ancient DNA: reconstruction of the biological history of Aldaieta necropolis
4. Jeremy Jackson honored by Harvard Museum of Natural History
5. Smithsonians National Museum of Natural History reveals ants as fungus farmers
6. Lemurs evolutionary history may shed light on our own
7. Man-made changes bring about new epoch in Earths history
8. Journal Sleep: Insomniacs are more likely to report a family history of the sleep disorder
9. Rebuilding the evolutionary history of HIV-1 unravels a complex loop
10. Microfossils disclose geologic history of eastern California
11. New study sheds light on Galápagos hawk evolutionary history
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Unheard of life history for a vertebrate
(Date:6/22/2016)... ANGELES , June 22, 2016 /PRNewswire/ ... identity management and verification solutions, has partnered ... edge software solutions for Visitor Management, Self-Service ... provides products that add functional enhancements ... partnership provides corporations and venues with an ...
(Date:6/16/2016)... , June 16, 2016 ... size is expected to reach USD 1.83 billion ... Grand View Research, Inc. Technological proliferation and increasing ... applications are expected to drive the market growth. ... , The development of advanced multimodal ...
(Date:6/7/2016)...  Syngrafii Inc. and San Antonio Credit Union ... integrating Syngrafii,s patented LongPen™ eSignature "Wet" solution into ... result in greater convenience for SACU members and ... existing document workflow and compliance requirements. ... Highlights: ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... -- Liquid Biotech USA , Inc. ... Research Agreement with The University of Pennsylvania ("PENN") ... patients.  The funding will be used to assess ... outcomes in cancer patients undergoing a variety of ... to support the design of a therapeutic, decision-making ...
(Date:6/24/2016)... , ... June 24, 2016 , ... While the majority ... as the Cary 5000 and the 6000i models are higher end machines that use ... height of the spectrophotometer’s light beam from the bottom of the cuvette holder. ...
(Date:6/23/2016)... 2016   Boston Biomedical , an industry ... to target cancer stemness pathways, announced that its ... Drug Designation from the U.S. Food and Drug ... including gastroesophageal junction (GEJ) cancer. Napabucasin is an ... cancer stemness pathways by targeting STAT3, and is ...
(Date:6/23/2016)... MA (PRWEB) , ... June 23, 2016 , ... ... Peel Plate® YM (Yeast and Mold) microbial test has received AOAC Research Institute ... platform of microbial tests introduced last year,” stated Bob Salter, Vice President of ...
Breaking Biology Technology: