During the 1990's frogs, salamanders, and toads with deformities skyrocketed. Scientist figured out that parasites that grew in snails were the cause of these deformities which usually caused extra limbs to grow from the amphibians. Researchers at the University of Colorado have collected evidence from over 345 wetlands and created 40 artificial ponds to come up with the hypothesis that amphibians in an ecosystem with greater biodiversity have a much lower risk of getting the parasite. The researchers found a pattern in their data. less diverse communities usually contain amphibians that are more susceptible to disease, while diverse communities usually contain species of amphibians that are resilient to disease. The researchers came up with the conclusion that amphibians in less diverse communities traded the ability to develop disease resistance for the trait to reproduce quickly.
NOS:
Science is based on evidence- the researchers collected samples from many wetland as well as created 40 artificial enviorments to check their data.
Hypothesis can be changed and developed- The scientists changed and developed their hypothesis as they gained new evidence.
http://www.sciencedaily.com/releases/2013/02/130213132319.htm
I really liked your article and paragraph but after reading it I have a few questions. What are the factors that lead to the deaths of the frogs and are any of the species at risk for extinction?
ReplyDeleteNewly introduced rainbow trout in Sierra Nevada were thought to be the culprits. However when scientists put frogs in trout free environments, they still disappeared. The new killer is a pathogenic fungus that caused the disease chytridiomycosis. David Wake, professor of integrative biology at UC Berekely decribes the fungus as "the most devastated wildlife disease ever recorded." Not to mention global warming and habitat destruction are also major killers.
Researchers found that nearly one third of amphibian species are threatened and many non-threatened ones are in danger to. The Yellow-legged Frog population has declined 95 to 98 percent over the past few years.
Link: http://www.berkeley.edu/news/media/releases/2008/08/12_extinction.shtml