Decline in frog populations

Pollutants are causing frog deformities such as multiple limbs, stunted growth or misplaced eyes. Researcher and naturalist Gary Fellers has been tracking the deformation and decline of the frog population in Yosemite National Park in California. He attributed these occurrences directly to "pesticides wafting over the Sierra Nevada mountains from...farms in California's Central Valley". ("What's Killing the Frogs?” Newsweek May 13, 2003, pg 46). Pollutants have varying effects on frogs. Some alter the central nervous system; others like atrazine cause a disruption in the production and se ...

See also:

Decline in frog populations, Decline in frog populations - Pollution, Decline in frog populations - Climate change, Decline in frog populations - Parasites, Decline in frog populations - Chytrid fungus, Decline in frog populations - Exotic species

Read more here: » Decline in frog populations: Encyclopedia II - Decline in frog populations - Pollution

Subclass Labyrinthodontia - extinct Subclass Lepospondyli - extinct Subclass Lissamphibia   Anura   Caudata   Gymnophiona Amphibians (class Amphibia) are a taxon of animals that include all tetrapods (four-legged vertebrates) that do not have amniotic eggs. Amphibians (from Greek αμφις "both" and βιος "life") generally spend part of their time on land, but they do not have the adaptations to an entirely terrestrial existence ...

Including:

• Amphibian - History of amphibians
• Amphibian - Classification
• Amphibian - Reproduction
• Amphibian - External references

Read more here: » Amphibian: Encyclopedia - Amphibian

Amphibians developed with the characteristics of pharyngeal slits/gills, a dorsal nerve cord, a notochord, and a post-anal tail at different stages of their life. They have persisted since the dawn of tetrapods 390 million years ago in the Devonian period, when they were the first four-legged animals to develop lungs. During the following Carboniferous period they also developed the ability to walk on land to avoid aquatic competition and predation while allowing them to travel from water source to water source. As a group they maintained th ...

See also:

Amphibian, Amphibian - History of amphibians, Amphibian - Classification, Amphibian - Reproduction, Amphibian - External references

Read more here: » Amphibian: Encyclopedia II - Amphibian - History of amphibians

In a story titled "The Frog and the Ox" of the Aesop's Fables, a frog, seeing an ox walking by, wanted to become as large and powerful as the ox. The poor frog filled itself full of air again and again. It exploded as a result. In the film Reflecting Skin, two boys insert a drinking straw into a toad's cloaca and inflate it, leaving it on the side of a path. The first person to come by and see the poor suffering toad bends over to inspect it, only to have ...

See also:

Exploding toad, Exploding toad - Description, Exploding toad - Explanations, Exploding toad - Exploding amphibians in fiction

Read more here: » Exploding toad: Encyclopedia II - Exploding toad - Exploding amphibians in fiction

Berlin veterinarian Franz Mutschmann collected corpses and performed autopsies. From his work, it was determined that the phenomenon was linked to a recent influx of predatory crows to the area. The cause was a mixture of crow attacks and the natural puff up defense of the toads. Crows attacked the toads to pick through the skin between the amphibian's chest and abdominal cavity, picking out the liver, which appears to be a delicacy for Crows in the area. In a defensive move, the toads begin to blow themselves up, which in turn, due to the h ...

See also:

Exploding toad, Exploding toad - Description, Exploding toad - Explanations, Exploding toad - Exploding amphibians in fiction

Read more here: » Exploding toad: Encyclopedia II - Exploding toad - Explanations

According to worldwide media reports in late April 2005, numerous toads in the Altona district of Hamburg were observed by nature protection officials to swell up with gases and explode, propelling their innards for distances of up to one metre. These incidents prompted local residents to refer to the area's lake—home to the toads—as "Tümpel des Todes" (Pool of Death). The incidents were reported as occurring with greatest frequency between 2 and 3 a.m. Werner Smolnik, environmental movement worker, stated on April 26, 2005 at least 1,000 toads had di ...

See also:

Exploding toad, Exploding toad - Description, Exploding toad - Explanations, Exploding toad - Exploding amphibians in fiction

Read more here: » Exploding toad: Encyclopedia II - Exploding toad - Description

For the purpose of reproduction most amphibians are bound to fresh water. A few tolerate brackish water, but there are no true sea water amphibians. Several hundred frog species in adaptive radiations (e.g., Eleutherodactylus, the Pacific Platymantines, the Australo-Papuan microhylids, and many other tropical frogs), however, do not need any water whatsoever. They reproduce via direct development, an ecological and evolutionary adaptation that has allowed them to be completely independent from free-standing water. Almost all of these frogs l ...

See also:

Amphibian, Amphibian - History of amphibians, Amphibian - Classification, Amphibian - Reproduction, Amphibian - External references

Read more here: » Amphibian: Encyclopedia II - Amphibian - Reproduction

Traditionally the amphibians are taken to include all tetrapods that are not amniotes. Recent amphibians all belong to a single subgroup of these, called the Lissamphibia. Recently there has been a tendency to restrict the class Amphibia to the Lissamphibia, i.e. to exclude tetrapods that are not more closely related to modern forms than they are to modern reptiles, birds, and mammals. There are two ancient, extinct, subclasses: Subclass Labyrinthodontia (paraphy ...

See also:

Amphibian, Amphibian - History of amphibians, Amphibian - Classification, Amphibian - Reproduction, Amphibian - External references

Read more here: » Amphibian: Encyclopedia II - Amphibian - Classification

Researcher Joseph Kiesecker focused research on a rural area of Pennsylvania where trematodes were present in ponds. His research indicated that frogs sheltered from the infiltration of parasites developed normally, while those that were exposed developed deformities. He also monitored the pesticide levels in the same ponds and found a magnification in the rate of parasitism in the polluted ponds suggesting that the presence of the pollutants reduces the frog’s immune response to parasitism. ("Pesticides Mess with Immunity" J. Pickrell Science News. July 13, 2003, p. 20) See also:

Decline in frog populations, Decline in frog populations - Pollution, Decline in frog populations - Climate change, Decline in frog populations - Parasites, Decline in frog populations - Chytrid fungus, Decline in frog populations - Exotic species

Read more here: » Decline in frog populations: Encyclopedia II - Decline in frog populations - Parasites