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Sharks - Free Sample

The underside of the pectoral fin has a black tip. A black axillary spot can be found at each pectoral fin insertion. This distinctive feature is missing on Mediterranean sharks. An Unmistakable Dentition The snout is conical. The five gill slits are relatively long and are all located at the formation of the pectoral fins. The first dorsal fin resembles an isosceles triangle. Its formation still lies within the area of the pectoral fins. The anal fin is located behind the base of the second dorsal fin. The tail fin is crescentic and both parts of the fin are well developed. A strong horizontal keel is located on both sides of the tail base. It reaches into the caudal fin, rein-forcing its strength. A secondary smaller keel, like the related porbeagle (Lamna nasus) is missing. The great white shark has relatively few but very large triangular teeth with a wide base and has an additional denticulation of cutting teeth. Above all, it can be distinguished from other sharks, like the mako or bull shark, primarily by its dentition. Late Maturity Females first reach sexual maturity at a length of 4.5 to 5 meters and an age of about 12-18 years, with males from 3.5 to 4.1 meters and 7-10 years of age. Little is known about the shark’s mating behavior. Bite marks on the females pectoral fins suggest, however, that the male, like other sharks, bites into the female for sexual intercourse thus enabling penetration in this manner. The females presumably become pregnant in two year intervals. Verified litter sizes range from 5-10 young fish. The embryos eat other unfertilized eggs in large numbers once they hatch from the embryonic membrane while still in the uterus. The embryos swallow the teeth that fall out during this event to recycle calcium and other minerals. The females give birth to an average of seven males with a length of 120-150 centimeters after a gestation period of presumably 12-18 months. Young sharks weigh 20-30 kg at birth, quickly growing at first at a rate of 20-30 cm per year (perhaps even faster Great White Shark


Sharks - Free Sample
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