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:7/20/2017)... Delta (NYSE: DAL ) customers now can use fingerprints instead ... National Airport (DCA). ... Delta launches biometrics to board aircraft at Reagan Washington National Airport ... Delta,s biometric boarding pass experience that launched in ... the boarding process to allow eligible Delta SkyMiles Members who are enrolled ...
(Date:6/23/2017)... ITHACA, N.Y. , June 23, 2017  IBM ... in dairy research, today announced a new collaboration using ... the chances that the global milk supply is impacted ... project, Cornell University has become the newest academic institution ... Chain, a food safety initiative that includes IBM Research, ...
(Date:5/23/2017)... GENOA, Italy , May 23, 2017  Hunova, the first robotic ... and trunk, has been officially launched in Genoa, Italy ... Europe and the USA . The ... launched on the market by the IIT spin-off Movendo Technology thanks to ... view the Multimedia News Release, please click: ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... ... October 10, 2017 , ... ... business process optimization firm for the life sciences and healthcare industries, announces a ... in San Francisco. , The presentation, “Automating GxP Validation for Agile Cloud Platforms,” ...
(Date:10/9/2017)... 2017  BioTech Holdings announced today identification and ... ProCell stem cell therapy prevents limb loss in ... demonstrated that treatment with ProCell resulted in more ... compared to standard bone marrow stem cell administration.  ... reduction of therapeutic effect.  ...
(Date:10/9/2017)... ... October 09, 2017 , ... At its national board meeting in ... professor in Harvard University’s Departments of Physics and Astronomy, has been selected for membership ... the winning team for the 2015 Breakthrough Prize in Fundamental physics for the discovery ...
(Date:10/9/2017)... Antonio, Texas (PRWEB) , ... ... ... new study published on October 5, 2017, in the medical journal, Epilepsia, ... equivalence with the gold standard, video EEG, in detecting generalized tonic-clonic seizures ...
Breaking Biology Technology: