Fiddler crab two weeks. Fiddler crabs such as "Uca mjoebergi" have been shown to bluff about their fighting ability. Upon regrowing a lost claw, a crab will occasionally regrow a weaker claw that nevertheless intimidates crabs with smaller but stronger claws. This is an example of dishonest signalling. The dual functionality of the major claw of fiddler crabs has presented an evolutionary conundrum in that the claw mechanics best suited for fighting do not match up with the mechanics best suited for a waving display. The internal classification of the genus "Uca" is unstable, but it contains around 100 species arranged among
Planalto hermit Planalto hermit The planalto hermit ("Phaethornis pretrei") is a species of bird in the family Trochilidae, the hummingbirds. It is found in eastern and south-central Brazil, eastern Bolivia, Paraguay, and marginally in north-western Argentina. It is usually easily recognized by its relatively large size, broad white tips to all the rectrices, and cinnamon-buff underparts and rump – the latter contrasing clearly with its tail and remaining upperparts. This is essentially a non-forest hermit, being found in a wide range of open and semi-open habitats, including Caatinga, Cerrado, and the Pantanal. It is widespread and generally common, and therefore considered to