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:1/26/2017)... -- Acuity Market Intelligence today released the 2017 "Ten ... characterizes 2017 as a "breakout" year for biometrics ... new understanding of the potential benefits these technologies ... are often perceived as threats to privacy and ... Acuity Market intelligence. "However, taken together these technologies ...
(Date:1/24/2017)... YORK , Jan. 24, 2017 ... study of the laboratory use of nuclear magnetic ... 363 experienced end-users and profiled current practices, developments, ... years, as well as growth and opportunities. These ... Instrument suppliers, NMR instruments, needs and innovation requirements, ...
(Date:1/23/2017)... latest mobile market research from Acuity Market Intelligence reveals ... average price of a biometric smartphone decreased from $849 ... are now 120 sub-$150 models on the market at ... a year ago at an average price of $127. ... Acuity Market Intelligence Principal, "Biometric Smartphones are a global ...
Breaking Biology News(10 mins):
(Date:2/22/2017)... 22, 2017  Aratana Therapeutics, Inc. (NASDAQ: PETX), a pet ... innovative biopharmaceutical products for companion animals, will host a live ... ET to discuss financial results from the fourth quarter and ... participants and investors may access the audio webcast ... ...
(Date:2/22/2017)... (PRWEB) , ... February 22, 2017 , ... Park ... free AFM Luncheon for all SPIE attendees and Park customers ... just one block from the San Jose Convention Center. The luncheon will feature ...
(Date:2/22/2017)... Scientists propose in Nature blocking ... Gaucher and maybe other lysosomal storage diseases as a ... current therapies. An international research team led ... also included investigators from the University of Lübeck in ... 22. The study was conducted in mouse models of ...
(Date:2/22/2017)... , ... February 22, 2017 , ... ... and development of precision treatments for neurodegenerative diseases, today announced it has issued ... ProMIS approach.” This is one of a series of commentaries from ProMIS’s scientific ...
Breaking Biology Technology: