What is Nurse shark?
{{Taxobox | name = Nurse shark | image = Nurse shark.jpg | status = DD | status_system = IUCN3.1 | regnum = [[Animal]]ia | phylum = [[Chordata]] | classis = [[Chondrichthyes]] | ordo = [[Orectolobiformes]] | familia = [[Ginglymostomatidae]] | genus = '''''Ginglymostoma''''' | species = '''''G. cirratum''''' | binomial = ''Ginglymostoma cirratum'' | range_map = Ginglymostoma_cirratum_distmap.png | range_map_caption = Range of the Nurse shark (In blue) }} The '''nurse shark''' (''Ginglymostoma cirratum'') is a bottom-dwelling [[shark]], and is the only known [[species]] in the [[genus]] '''''Ginglymostoma'''''. They range in length from {{convert|2.1|-|2.7|m}}, and weigh {{convert|75|-|120|kg}}. Nurse sharks feed on [[crustacean]]s, [[mollusk]]s, [[sea snake]]s, [[fish]], [[coral]], and [[tunicate]]s. The Nurse shark is common in the [[coastal]] [[tropical]] and [[subtropical]] waters of the eastern [[Pacific Ocean|Pacific]] and the [[Atlantic Ocean]]. Nurse sharks are [[nocturnal]], and are very [[wikt:sluggish|sluggish]] and are [[wikt:harmless|harmless]] unless bothered. == Description== Nurse sharks have two spineless, rounded [[dorsal fin]]s, with the first dorsal fin being much larger than the second, and they have one [[anal fin]]. The first dorsal fin is located over the [[pelvic fin]]s. The [[caudal fin]] is more than one quarter of the total [[shark|shark's]] length. The sub-terminal [[mouth]] is placed well in front of the [[eye]]s, the [[spiracle]]s are small, and there are long barbels on the mouth. The Nurse shark has nasoral grooves, but there is no perinasal groove. Adult Nurse sharks are usually light yellow to dark brown in colour. The young that are up to 60 cm (24 inches) long have small black spots, with an area of lightness surrounding each spot, covering the entire body. Larger young which are 70-120 cm long (28-47 inches) are capable of limited colour changes. Studies show that Nurse sharks kept out of sunlight become slightly lighter in colour, as compared to Nurse sharks which are expos