I feel to share something about the little thermometers about which i came accross on my serach through net. They are none other thaan microbes which have their on role in detecion of temperature change.
Why are insects so ecologically important? "They carry diseases, they pollinate and they have economic impacts on crops and timber," says Hellmann, a biologist at the University of Notre Dame. In fact, almost 80 percent of the world's crop plants require pollination, and the annual value of insect-pollinated crops in the U.S. is about $20 billion. What's more, most of the multicellular living organisms on Earth are insects.
They are also particularly sensitive to climate change--as invertebrates, they can't regulate their own body temperatures--making them "great little thermometers,"
Most importantly, as climate change progresses, some insects may become trapped--like fish out of water--in habitats that can no longer support them. The insects may therefore go extinct or lose genetically important segments of their populations. But other species, and no one knows which ones yet, may be able to reach cooler climates by moving north on their own.
Will such mobile species be able to survive on the unfamiliar plants living in their new habitats? To help answer that question, Pelini conducted laboratory experiments that involve exposing caterpillars of two butterfly species to climates and plants that occur across their ranges, and then monitoring the growth and survival rates of these groups.
She will soon announce in the journal Proceedings of the National Academy of Sciences (PNAS) how populations of these two butterfly species that live at the edges of their ranges will be affected by climate change and the various factors that may limit or reduce their northward expansion.
Hellmann is currently following up on Pelini's research by surveying thousands of genes in the two butterfly species in order to identify the genes that are turned off or on by climate change. These studies are designed to reveal the genetic bases for the tolerance of some insect species to climate change and the intolerance of others.
There is a difference between conducting managed relocation and introducing invasive species to new ecosystems. "If we thought that a species had the potential to become invasive, meaning it might become harmful where it was introduced, we would not want to consider that species as a candidate for managed relocation," says Hellmann. Species that are less likely to become invasive include those that are endangered or highly specialized or that we have some way of controlling.
we just have to make sure that our managed species shouldn't turn into invasive species. And that is the heart of the debate over managed relocation
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