Description
The zebra shark has a cylindrical body with a large, slightly flattened head and a short, blunt snout. The eyes are small and placed on the sides of the head; the spiracles are located behind them and are as large or larger. The last 3 of the 5 short gill slits are situated over the pectoral fin bases, and the fourth and fifth slits are much closer together than the others. Each nostril has a short barbel and a groove running from it to the mouth. The mouth is nearly straight, with three lobes on the lower lip and furrows at the corners. There are 28–33 tooth rows in the upper jaw and 22–32 tooth rows in the lower jaw; each tooth has a large central cusp flanked by two smaller ones.
There are five distinctive ridges running along the body in adults, one along the dorsal midline and two on the sides. The dorsal midline ridge merges into the first dorsal fin, placed about halfway along the body and twice the size of the second dorsal fin. The pectoral fins are large and broad; the pelvic and anal fins are much smaller but larger than the second dorsal fin. The caudal fin is almost as long as the rest of the body, with a barely developed lower lobe and a strong ventral notch near the tip of the upper lobe. The zebra shark attains a length of 2.5 m (8.2 ft), with an unsubstantiated record of 3.5 m (11.5 ft). Males and females are not dimorphic in size.
The color pattern in young sharks is dark brown above and light yellow below, with vertical yellow stripes and spots. As the shark grows to 50–90 cm (20–35 in) long, the dark areas begin to break up, changing the general pattern from light-on-dark stripes to dark-on-light spots. There is substantial variation in pattern amongst adults, which can be used to identify particular individuals. In 1964, a partially albino zebra shark completely lacking spots was discovered in the Indian Ocean. The shark, a 1.9 m (6.2 ft) long mature female, was unusual in that albino animals rarely survive long in the wild due to their lack of crypsis.
Read more about this topic: Zebra Shark
Famous quotes containing the word description:
“I fancy it must be the quantity of animal food eaten by the English which renders their character insusceptible of civilisation. I suspect it is in their kitchens and not in their churches that their reformation must be worked, and that Missionaries of that description from [France] would avail more than those who should endeavor to tame them by precepts of religion or philosophy.”
—Thomas Jefferson (1743–1826)
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (1886–1965)
“He hath achieved a maid
That paragons description and wild fame;
One that excels the quirks of blazoning pens.”
—William Shakespeare (1564–1616)