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Poison Dart Frogs |
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Dart frogs are native to the tropical rain
forests of Central and South America. Primarily the southern parts of Central America and
the northern half of South America. They are primarily ground dwellers but some make their
way into the trees foraging for food and possible egg laying sites. The name Poison Dart
Frog comes from the use of a particular dart frog, Phyllobates terribilis, by the South
American Indians to prepare their blow darts. They rub the dart on the back of the frog,
which being irritated by this, secretes the toxins from its skin. Another common, albeit
more cruel way is to jam the dart right through the frog, killing it dead (obviously).
They use these darts in their blow guns to kill monkeys and other things living in the
canopy of the rain forests to use for food, clothing, religious ceremonies, barmitzvahs,
etc. Not all of the toxins produced by these frogs is deadly. Most are not even close to
the toxicity of P. terribilis, which some say could kill a man on contact. One might ask
how these frogs are handled in captivity. Luckily for the herpetoculturist, after long
periods in captivity these frogs lose the ability to produce the toxins secreted from the
skin. Most species in captivity can be handled with no fear of being poisoned. With most
frogs on the market today being third or more generations captive bred, there is little
chance that they are toxic at all. The most widely accepted reason for this has to do with
diet. In the rainforests of South America, there are plants that contain certain types of
Alkaloids. The insects that live on these plants take in the Alkaloids, and are in turn
eaten by the frogs. The dart frogs have the ability to metabolize these Alkaloids along
with other chemicals in their bodies into complex toxins that are then secreted from the
skin. In captivity, dart frogs are raised on a variety of small insects but the staple is
laboratory bred fruit flies. None of these insects ingest the Alkaloids necessary to
produce the toxins, so after a while the poison dart frogs become, well, just dart frogs.
One of the many fascinations of the dart frogs is the parental care given by the adults.
In all species the adults will watch over the newly laid eggs, protecting them from
predators until the eggs hatch into tadpoles. At this point the adult will lower its
backside to where the tadpoles can swim up onto their back. The tadpoles are then
transported either one at a time or in groups, depending on the species, to a suitable
pool of water, often the water filled axils of a bromeliad, for housing the tadpole
through to the next stage of its growth. At this point several species take the task of
parental care one step further by feeding the young tadpoles until the metamorphosis into
little frogs occurs. The female visits each tadpole on a regular basis and deposits a food
egg, basically an infertile egg, for the tadpoles to eat. She will continue this ritual
until the young frogs emerge.
