You’ve heard the saying, adapt or die. How about adapt and die? Reading a new scientific report by David B. Wake and Vance T. Vredenburg, on the mass extinction that Amphibian Ark aims to avert, a new thought surfaces: Amphibians outlived the dinosaurs because of their adaptability — hey, they’re the Transformers of the animal world — yet the sensitive biomechanisms that make adaptability possible also put them at the greatest risk from new dangers created by man. Hence, their suffering today represents a canary in the coal mine warning us that the planet is in trouble. I recommend reading the full story from the National Academy of Sciences (of USA), but I pasted an excerpt below. And, the Los Angeles Times published a piece on it.

Why this should be has perplexed amphibian specialists. A large number of factors have been implicated, including most prominently habitat destruction and epidemics of infectious disease (19); global warming also has been invoked as a contributing factor (20). What makes the amphibian case so compelling is the fact that amphibians are long-term survivors that have persisted through the last four mass extinctions. Paradoxically, although amphibians have proven themselves to be survivors in the past, there are reasons for thinking that they might be vulnerable to current environmental challenges and, hence, serve as multipurpose sentinels of environmental health. The typical life cycle of a frog involves aquatic development of eggs and larvae and terrestrial activity as adults, thus exposing them to a wide range of environments. Frog larvae are typically herbivores, whereas adults are carnivores, thus exposing them to a wide diversity of food, predators, and parasites. Amphibians have moist skin, and cutaneous respiration is more important than respiration by lungs. The moist, well vascularized skin places them in intimate contact with their environment. One might expect them to be vulnerable to changes in water or air quality resulting from diverse pollutants. Amphibians are thermal-conformers, thus making them sensitive to environmental temperature changes, which may be especially important for tropical montane (e.g., cloud forest) species that have experienced little temperature variation. Such species may have little acclimation ability in rapidly changing thermal regimes. 



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