poison dart frog

Phyllobates bicolor, a poison dart frog native to the Colombia region of South America. Like other species of poison dart frogs, it is brightly colored (aposematic coloration), an adaptation for diurnal foraging in which predators can easily recognize and avoid these poisonous frogs. Although it is highly toxic, the skin of this species contains less batrachotoxin than the similar golden poison frog P. terribilis. Batrachotoxin is a steroidal alkaloid secreted from skin glands and is deadly to other small animals. It blocks neuromuscular transmission, resulting in muscle and respiratory paralysis and death. Extrapolating from the lethal dosage (LD) in rats, approximately 136 micrograms of this alkaloid is the lethal dosage for a 150 pound (68 kilogram) person. This minute amount is roughly equivalent to the weight of two or three grains of ordinary table salt (NaCl).

Dendrobates tinctorius, a strikingly beautiful poison dart frog native to tropical rain forests of the Guianas in the northeastern shoulder of South America. Dendrobates frogs produce a poison called pumiliotoxin, which is not as deadly as the batrachotoxin produced by Phyllobates frogs.

Dendrobates tinctorius, a strikingly beautiful poison dart frog native to tropical rain forests of the Guianas in the northeastern shoulder of South America. Dendrobates frogs produce a poison called pumiliotoxin, which is not as deadly as the batrachotoxin produced by Phyllobates frogs.

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The blue poison dart frog (Dendrobates azureus), another striking species native to southern Surinam, near the border with Brazil in South America. This is one of the most beautiful frogs in the world. Dendrobates frogs produce a poison called pumiliotoxin, which is not as deadly as the batrachotoxin produced by Phyllobates frogs.

Strawberry poison dart frogs Dendrobates pumilio, a remarkable species native to tropical rain forests of Nicaragua, Costa Rica and Panama. Although their eggs are laid among the leaves, the newly hatched larvae are carried on the backs of the parents to a pool of water or water-filled bromeliad. D. pumilio is especially remarkable because the female parent attends her developing tadpoles by providing them with nutritive, unfertilized eggs. The bright coloration of these frogs is considered by some biologists to be an example of “warning coloration” (aposematic coloration), where would-be predators avoid the frogs because of their bitter, toxic, alkaloid secretions. This avoidance behavior is especially true if the predator has had a previous unpleasant encounter with these brightly colored frogs.

A strawberry poison dart frog Dendrobates pumilio. This strikingly beautiful species is native to tropical rain forests of Nicaragua, Costa Rica and Panama. The bright coloration of these frogs is considered by some biologists to be an example of “warning coloration” (aposematic coloration), where would-be predators avoid the frogs because of their bitter, toxic, alkaloid secretions. This avoidance behavior is especially true if the predator has had a previous unpleasant encounter with these brightly colored frogs.

source : http://waynesword.palomar.edu/dartfrog.htm