show brighter coloration, are territorial, and are aggressive toward other males. Females select mates based on coloration (mainly dorsal), calling perch location, and territory. Taxonomy Dart frogs are the focus of major phylogenetic studies, and undergo taxonomic changes frequently. The family Dendrobatidae currently contains 16 genera, with about 200 species. Color morphs Some poison dart frogs species include a number of conspecific color morphs that emerged as recently as 6,000 years ago. Therefore, species such as Dendrobates tinctorius, Oophaga pumilio, and Oophaga granulifera can include color pattern morphs that can be interbred (colors are under polygenic control, while the actual patterns are probably controlled by a single locus). Differing coloration has historically misidentified single species as separate, and there is still controversy among taxonomists over classification. Variation in predation regimens may have influenced the evolution of polymorphism in Oophaga granulifera, while sexual selection appears to have contributed to differentiation among the Bocas del Toro populations of Oophaga pumilio. Toxicity and medicine The chemical defense mechanisms of the Dendrobates family are the result of endogenous means. Essentially this means that their ability to defend has come through the consumption of a particular diet. In fact, captive raised species exhibited non-detectable levels of toxins whereas the wild-caught species did as a result of their calcium and vitamin-rich Drosophila and cricket diet. The secretion of these chemicals is released by the granular glands of the frog. The discharge happens as a result of acetylcholine being released into the body which triggers the sympathetic or parasympathetic system depending on the species. The chemicals secreted by the Dendrobatid family of frogs are unique alkaloids that consist of greatly different and unique chemical structures and toxicity. It has been suggested that initially the granular glands were solely responsible for the production and synthesis of the diverse toxins in different species of Dendrobates, then through evolution the glands were adapted to also be responsible for storage, and then finally even the secretion of them upon triggering. Many poison dart frogs secrete lipophilic alkaloid toxins such as allopumiliotoxin 267A, batrachotoxin, epibatidine, histrionicotoxin, and pumiliotoxin 251D through their skin. Alkaloids in the skin glands of poison dart frogs serve as a chemical defense against predation, and they are therefore able to be active alongside potential predators during the day. About 28 structural classes of alkaloids are known in poison dart frogs. The most toxic of poison dart frog species