Here is another interesting article I found about what could happen in the future for reptiles. Reptiles, as we all know, need sun and warmth to regulate their body temperatures. But according to this article, the effects of global warming might affect their ability to regulate their internal temperature. Reptiles are pretty much stuck, unless they can develop some endothermic forms. I know of some people who thinks they can. Who knows? Evolution has done much the same thing in the past. There is no reason it cannot happen again.
I've been down in the dumps all day. I just heard some things about JD Fortune that I wish I hadn't! But that is kinda useless ramble to this blog. I am still faithful to INXS, but I would like to think I would be faithful to JD as well. But the most hurtful thing is what it's done to someone I hold dear as an online buddy. She lost friends because she told them that she doesn't want to support JD anymore. It's a long story! Well, I've already let her know that I will always be there for her. No matter what her other so-called friends have done. I just wanted her to realize that.
http://dsc.discovery.com/news/2009/02/17/cold-blooded-warming.html
Reptiles May Overheat in Warmer Future
Dani Cooper, ABC Science Online
Feb. 17, 2009 -- Commonly known as being cold-blooded and in need of some sunshine, the world's ectotherms may be struggling to keep cool in the future.
The finding raises concerns about how animals that regulate their body heat using air temperature will cope in a warmer world predicted by climate change.
Writing in this week's issue of Proceedings of the National Academy of Sciences, a team of Australian and U.S. researchers say the impact of climate change on ectotherms will depend on how global warming-induced changes in habitat alter the ability to access shade.
Another factor will be the animals' capacity to alter the seasonal timing of their activity and reproduction.
Lead author Michael Kearney, of the University of Melbourne's Department of Zoology, said the results of their modeling are counter-intuitive.
"The majority of the world's animals are cold-blooded," Kearney said. "So if it gets warmer you would think it might be better for them."
However, Kearney said using modeling that combines spatial data on climate, geography and vegetation, with behavioral models they were able to determine whether the priority of thermoregulating ectotherms such as reptiles and insects was to keep warm or stay cool.
"What we've found is that for a large fraction of the planet's animals their main priority is to thermoregulate to stay cool," Kearney said, "and global warming is going to make keeping cool harder."
Not only will air temperatures be higher, he said, but the availability of habitat in which to shade could be altered.
For the study, Warren Porter, of the University of Wisconsin's Department of Zoology, and the University of Sydney's Rick Shine studied the effects of climate change on a small Australian lizard known as the heath monitor (Varanus rosenbergi).
The modeling was based on the lizard living in three different climate zones -- temperate coastal, Melbourne; arid continental, Alice Springs; and tropical coastal, Darwin.
The consequences of three different behaviors -- sitting in full sun, sitting in full shade and moving in and out of shade to maintain a preferred body temperature -- in those three zones was then mapped.
Kearney said the big surprise of their work was to find that so-called "cold-blooded animals" were more focused on keeping cool than on warming up.
This means increased temperatures predicted under climate change scenarios would impact greatly on animal behavior. He said these effects could include changing the timing of activities, such as foraging and reproduction, which could have a flow-on effect to "whole ecosystems."
Warmer environments may also increase energy costs for the animal while also constraining activity time as they spend more time seeking shade.
"Effectively their rent goes up, but the time they've got to find an income goes down," Kearney said.
Under the modeling Kearney said it is clear there will be a "mismatch between required and available shade" in regions such as northern Australia and northern Africa, where there is too little shade, and temperate Australia, North America and Europe, which has too much shade.
"Human activities such as deforestation are dramatically altering the degree of shading available for thermoregulating ectotherms in tropical regions," the authors wrote in the paper. "Climate change will also alter vegetation cover through processes such as increased carbon dioxide and changed fire frequency."
Kearney said the ability of a species to tolerate climate change will be whether it can modify the seasonal timing of activities such as reproduction.
"Without such liability, the feasible options to maintain population viability are greatly limited and likely will require substantial evolutionary shifts," he said.
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