Global warming may reduce lifespan of cold-blooded species

Cold-blooded animals, including fish, amphibians, crustaceans, and reptiles, seem to live longer under cooler conditions, suggesting that warming climate could have impacts on the lifespan of creatures whose body temperatures vary with the temperature of their surroundings, report researchers writing in the Proceedings of the National Academy of Sciences (PNAS).

Stephan Munch and Santiago Salinas of Stony Brook University examined lifespan data for 90 species from terrestrial, freshwater, and marine environments, comparing the differences in lifespan across an individual species' range. They found significant differences. For example, pearl mussels in Spain (latitude: 43°N) have a maximum lifespan of 29 years, while in Russia the species lives nearly 200 years (latitude: 66°N).

Munch and Salinas determined that "ambient temperature is the dominant factor controlling geographic variation of lifespan within species." They found that the observed relationship between temperature and lifespan was similar to the relationship that predicted by the metabolic theory of ecology (MTE), a model that explains how life history, population dynamics, geographic patterns, and other ecological processes scale with an organism's body size and temperature. Overall the lifespan in 87 percent of the non-sessile species studied was explained by MTE.

“You can think of an animal as a beaker in which chemical reactions are taking place,” said Salinas. “The same rules that apply to a liquid inside a beaker should apply to animals. Chemists have a relationship for how an increase in temperature will speed up reaction rates, so the MTE borrows that relationship and applies it--with some obvious caveats--to living things.”

The researchers say the findings suggest that climate change could trigger changes in lifespans among cold-blooded species.

"It is interesting to consider how cold-blooded species are likely to react in the face of global warming,” said Salinas. “Because of the exponential relationship between temperature and lifespan, small changes in temperature could result in relatively large changes in lifespan. We could see changes to ecosystem structure and stability if cold-blooded species change their life histories to accommodate warmer temperatures but warm-blooded species do not."

Research published last week suggests that warmer climate could favor smaller species over larger ones. Meanwhile NOAA announced earlier this month that global ocean temperatures in June reached the highest level since record-keeping began in 1880.


Taken from :
www.mongabay.com

In the dark, bats identify each other by voice

Individual bats have the ability to tell the difference between other bats just by the sound of their voice, according to a study published in PLoS Computational Biology.

Researchers from the University of Tuebingen, Germany found that the greater mouse-eared bat could distinguish between their fellows’ echolocation calls. A subject bat was tested by having to select between two others depending on their calls. The subject bats chose correctly over 80 percent of the time.


The greater mouse-eared bat is native to Europe. Photo by: Manuel Warner.
"If you think of this in comparison with humans, it's like being able to recognize a person just by listening to the same one-syllable yell in different voices, " head of the study, Dr. Yossi Yovel told the BBC. "The bats learned the voice by listening to hundreds of very short 'yells', but they then were able to recognize an individual based on one single yell."

Researchers then produced a computer model that reproduced the recognition behavior displayed by the bats. The model suggests that the bat’s calls contain spectral energy distribution that is unique to every individual, allowing the bats to tell one another apart simply by listening.

CITATION: Yovel Y, Melcon ML, Franz MO, Denzinger A, Schnitzler H-U (2009) The Voice of Bats: How Greater Mouse-eared Bats Recognize Individuals Based on Their Echolocation Calls. PLoS Comput Biol 5(6): e1000400.

Taken from mongabay.com
June 08, 2009

From the Rainforest to your home: Happy World Biodiversity Day!

The United Nations proclaimed May 22 the International Day for Biological Diversity (IDB) to increase understanding and awareness of biodiversity issues.
Proyecto Asis is committed to preserving the flora and fauna, as well as to encourage our visitors and resident people on the importance of having a development in harmony with nature.
What is happening with the human race?
1) We are eliminating populations and species faster than we can discover new ones.
2) We cut down thousands of acres of virgin forest every year.
3) We are polluting our environment and changing background environmental conditions faster than nature can respond.
4) We worry about the loss of species usually once it is too late to effectively do anything about it.
Stop right now and analyze the importance of biodiversity…
What can we do now?
It’s simple: Start planting in your own yard, take care of your pet animals and have respect for all the species that you can see in everywhere.
Take a time for volunteer. If you have the possibility to travel abroad, come and visit Proyecto Asis. Nature awaits you. Be the change you want to see in the world!.