12 Sharks: The Animal Answer Guide
pronounced shock, which was the name of a demonic, fishlike god. Appar-
ently, Europeans, prior to the exploratory ocean voyages of the sixteenth
century, did most of their fishing in rivers and lakes or very close to shore.
They had little experience with large oceanic sharks. When they eventually
traveled to the New World, they were astonished by, and had no name for,
the large, fiercely predatory sharks of the tropics. So they adopted the local
word for these animals and carried it back to Europe. Another possibility
is a German term, Schurke, which refers to a shifty criminal. However, the
modern German term for “shark” is Hai or Haifisch.
Nusse is another old English name for sharks in general and may be the
origin of the current names of various sharks referred to as nurse sharks
(Nurse Shark, Ginglymostoma cirratum, and Grey Nurse, Carcharias taurus,
also called Sand Tiger or Ragged Tooth). However, another possible origin
for the Nurse Shark’s name relates to its well-known ability to create suc-
tion pressure when feeding, as shown in laboratory studies. Nurse Sharks
are thought to suck lobsters and other prey out of holes, although veri-
fication of this ability in nature is lacking. People other than researchers
are familiar with a Nurse Shark’s sucking habits. Local names for relatives
of the Nurse Shark suggest this behavior. In the island nation of Palau, a
tropical Pacific species, the Zebra Shark (Stegostoma fasciatum) is referred
to as metmut. This is the same word used to describe the suckling behavior
of nursing human infants. Sand Tigers, with their decidedly snaggletooth
appearance, are equipped to impale prey fish on long, pointed teeth, so it is
unlikely that their name has anything to do with sucking.
Where do sharks live?
Most sharks, skates, and rays and all chimaeras live in the ocean, from
the poles to the tropics and from the shoreline out to the middle of the
ocean. Among the elasmobranchs, depths range from exceedingly shallow
water only a few feet deep, down to great ocean depths. Stingrays, gui-
tarfishes, and sawfishes feed on the bottom near the shoreline, one of the
reasons you should shuffle your feet when wading in shallow water where
stingrays may occur. Lemon Sharks (Negaprion brevirostris), including large
individuals 3 m (about 9 or 10 ft) long, will swim in water so shallow their
dorsal fins and tail stick out of the water. Large groups of Blacktip Reef
Sharks (Carcharhinus melanopterus) also swim in water shallower than their
body depth. Chimaeras usually occur in water deeper than 80 m (250 ft),
with some species found as deep as 2,600 m (8,500 ft).
Sharks in general do not live in the greatest depths of the ocean, espe-
cially when compared with bony fishes. Bony fishes have been caught in
bottom nets in the Puerto Rico Trench at a depth of 8,370 m (27,500 ft).
http://www.ebook3000.com