THE DANGER IN THE BEAUTY OF POISON DART FROGS

Dendrobatidae is a family of toxic frogs formed by 16 genera and around 200 species. They are native to Central and South America and they generally live in tropical rainforests, although they are found in other environments too, as we will talk about later. They are known as poison dart frogs, poison frogs or poison arrow frogs. Their name comes from the fact that indigenous Americans used their toxins as venom for their darts by poisoning the tip. If you are interested in learning more about their colors, their toxins and their habitats, stay with us throughout this article.

Strawberry poison dart frog over a leaf. 

When one of these frogs is observed, the featured that stands out the most about them is their flashy and bright colors. These colors, as beautiful as they are, are not there to delight our eyes, but rather to warn us. This characteristic is called aposematism, which is basically to be as flamboyant as possible to avoid predators. By showing these colors, poison dart frogs are sending a message about their dangerousness. They want predators to know how toxic they are to scare them and avoid being eaten. Generally speaking, the brighter the colors, the more dangerous the frog is.

They must be so colorful because their size does not help them stand out. They are small frogs, with a length ranging from 0.59 (1.5 cm) inches to 2.36 inches (6 cm). Their little size is also one of the causes of why they evolved to be toxic, as they can not use their strength to defend themselves.

As most amphibians, they are found in moist areas, predominantly tropical rainforests. They can also be found in mountains, near rivers, lakes and swamps and seasonally flooded grasslands. In these environments, they lay their eggs and take care of their tadpoles. Some species wait for the eggs to hatch, then carry their tadpoles on the back and then release them in a nutrient rich pool. Other species lay their eggs under the leaf litter in the forest floor. To feed their tadpoles, mothers lay unfertilized nutrient-packed eggs.

Golden poison frog, the most venomous kind of dart frog.
Photo by: Brian Gratwicke
https://creativecommons.org/licenses/by/2.0/

As defense mechanism, these frogs release a lipophilic alkaloid toxin through their skin. This toxin keeps predators away from the frogs and increases their chance of survival. Poison dart frogs cannot actually synthetize the components of their toxins. They obtain them from a diet rich on beetles, therefore, they are not venomous when bred in captivity. Thanks to their toxicity, they can be diurnal species despite their size, as almost no animals are fool enough to try to eat them. However, there is a snake that can feed on these frogs without any consequences. It is called Erythrolamprus epinephalus and it is completely immune to their toxin.

These colorful and flashy creatures proof, once more, that beauty in wildlife usually means danger. They have found a way to defend themselves despite being small and they have demonstrated that you don’t have to be the strongest to survive, but the fittest.