A Few Frogs Mount Speedy Defence Against Pesticide Threat


There may be some hope for several species of frogs when it comes to resistance to a group of commonly used pesticides. One example is found in wood frogs (Lithobates sylvaticus) that are able to turn on the expression of a gene that responds to environmental pressures. In one generation the process called phenotypic plasticity enables some frogs to evolve much faster than scientists thought. This is some good news when you consider that one-third of frogs are threatened or extinct.

Andrew Blaustein, amphibian ecologist at Oregon State University, and his team discovered these frogs in areas near agricultural land in northwest Pennsylvania. Laboratory test looked at both pesticide-resistant frogs near agricultural sites and non-resistant frogs farther away. Test results indicated that the frog embryos and hatchlings far away from these fields did not have the same resistance, but quickly become tolerant when exposed to low levels of the pesticides.

Although scientist have observed only a few plant species evolving due to phenotypic plasticity, this is the first-known example of a vertebrate species developing pesticide resistance through this process.

Other species exhibiting this speedy carbaryl resistance is the grey tree frog (Hyla versicolor), and both species have also shown resistance to another pesticide, malathion. This doesn’t indicate that pesticide use should continue, but it does give some hope for the future of the amphibian species living near toxic environments. It may also indicate that use of pesticides may be a short-term solution for the intended targets of mites and beetles, as they may also develop resistance over time to the pesticides.

The arms race that the chemical companies have set us on is not a long-term solution as it destroys a majority of the species in our environment. Although there are great champions like the tree and wood frogs, a vast majority of species will be detrimentally affected by this chemical exposure, including humans. In the end, we may be left with limited biodiversity and resistant mites and beetles.

Great way to teach your kids about the world around them, take them on an amphibian photo hunt and help map out the species in your area.

Source: Frogs mount speedy defence against pesticide threat