Parasites Affects Frog Population A review written from an article...

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Parasites Affecting Frog Population

The number of healthy frogs in North America is rapidly decreasing due to a small parasite that results in the deformation of the frog population. University of Wisconsin graduate Pieter Johnson is studying the possible threat the parasite poses. Due to the increasing rate of production, man-made ponds are starting to outnumber natural wetlands and are forcing frogs to adapt to these inferior habitats. Ironically, it's lakes like these that the worm known as Ribeiroia flourish. However; these parasites are nothing new says Johnson, and have probably been around for thousands of years infecting small numbers of amphibians. Johnson has discovered this in his most recent research by testing samples from the past and present. These tests have shown that the parasite still lives and attacks amphibians. Though other researchers suggest that there may be more than one culprit guilty of the frog deformation such as, pesticides, retinoids, and UV rays. Yet even more than the host frog, the worm is dependant on a snail in which it reproduces asexually, without it the worm is deceased.

When the larvae roam out the snail shell they seek a host and attach themselves to the rear of the creature, burrowing in a cyst that affects the growth of frogs legs. The consequence results in missing or extra limbs, which hinders the frogs' movement and ability to escape predators.

He also hypothesizes that the worms' infectious manner may be the work of natural selection. In addition, the life cycle of the worm continues through the feces of other organisms launching the procedure again. Although, that's not Johnson's interest. It is the worms connection to the snail that has him so intrigued. Without the snails the worm cannot survive and these snails seem to live in ponds with lots...