Tetra a tall dorsal fin characterized by a short connection to the fish’s body. Additionally, tetras possess a long anal fin stretching from a position just posterior of the dorsal fin and ending on the ventral caudal peduncle, and a small, fleshy adipose fin located dorsally between the dorsal and caudal fins. This adipose fin represents the fourth unpaired fin on the fish (the four unpaired fins are the caudal fin, dorsal fin, anal fin, and adipose fin), lending to the name tetra, which is Greek for four. While this adipose fin is generally considered the distinguishing feature, some tetras (such
Caudal luring often in juvenile snakes and is most prevalent in vipers and pitvipers, but it also occurs in boas, pythons, tropidophiids, colubrids, and elapids of the genus Acanthophis. Caudal luring has been used as an experimental paradigm to investigate stimulus control and visual perception in viperid snakes. It has been suggested that caudal luring was involved in the evolution of the rattlesnake rattle. Attempts have been made to test this hypothesis, however, the evidence is contentious. There have been dubious reports of caudal luring and concomitant speculations. Prey luring in general is confounded by false interpretation. The difficulty is that there