Physical Characteristics and Special Adaptations
A. Size
1. Tigers are the largest living species of cat.
2. The head and body length of tigers varies from 1.4 to 2.8 m (4.6-9.2 ft.). Tail
lengths vary from 0.6 to 0.95 m (2-3.1 ft.). (2)
3. The largest tigers are found in the north, gradually becoming smaller in the south.
a. The Siberian tiger is the largest subspecies. Males weigh 180 to 306 kg (397-675
lb.), and females weigh 100-167 kg (221-368 lb.). (1)
b. Bengal tigers are slightly smaller, with males weighing 180 to 258 kg (397-569 lb.)
and females weighing 100 to 160 kg (221-353 lb.). (1)
c. The smallest living subspecies is the Sumatran. Males weigh 100 to 140 kg (221-309
lb.) and females weigh 75 to 110 kg (165-243 lb.). (1)
4. Tigers are sexually dimorphic (males and females are distinctly different in
appearance). Adult males of all subspecies are larger than adult females, and the males
grow a well-defined ruff of hair around their necks. (2)
B. Body
1. A tiger's body is built for capturing and killing large prey
through stealth and sudden attack. (2)
2. Powerful limbs and a flexible backbone enable tigers to quickly chase and catch prey
over short distances. Tigers can cover up to 10 m (33 ft.) in a single leap. (1)
a. A tiger's hindlimbs are longer than the forelimbs, an adaptation
for jumping. (8)
b. The forelimbs and shoulders are well-muscled, and the forelegs can twist inward,
enabling the tiger to grab and hold large prey. (2)
3. A tiger's feet (paws) have soft pads, and long, sharp, retractile
claws.
a. The underside of the paws have soft pads which allow tigers to quietly stalk their
prey. Unlike humans who are flat-footed, tigers walk on their toes. (3)
b. The forefeet have five claws which are used for attacking prey or other tigers. The
first claw, called a dew claw, is vestigial (reduced in
size) and does not reach the ground. Tigers keep the foreclaws sharp by scratching them on
"scratching posts" such as tree trunks.(3)
c. The hindfeet have four claws. The hindclaws are occasionally used to help bring down
large prey, and in defense against other tigers.
d. Tigers seldom climb trees, but are capable of doing so with the help of their front
and back claws. (1, 3)
e. When not in use, each claw is retracted (by ligaments) into a sheath of skin, which
protects it from excessive wear. To extend the claw from the sheath, muscular action is
needed to straighten the last toe bone and pull the claw forward. (3)
C. Head
1. A tiger's head is rounded and shortened, and the eyes face forward.
2. The jaws are short and powerful, and generally contain 30 teeth.
a. Incisor teeth help to grab hold of prey as well as pull meat off bones.
b. Canine teeth are used for biting and killing.
c. Premolars and molars are used for tearing and chewing. The carnassials of cats (the
fourth upper premolar and the first lower molar on each side of the jaw) are the most
scissorlike of all carnivores. They function like knife blades to slice meat.
d. Dental formula for tigers: I=3/3, C=1/1, P=3/2, M=1/1
D. Hair and coloration
1. Hair, or coat color, in tigers ranges from yellow to reddish-ochre.
a. Tigers in northern areas, like Russia and northern China, are usually lighter in
color than tigers in southern areas, like Malaysia and Sumatra. (2)
b. In general, Siberian tigers have light yellow coats; Bengals, lightish-yellow to
reddish-yellow; Indo-Chinese and South Chinese, reddish-orange; and Sumatrans,
reddish-ochre. (2)
2. A tiger's coat is transversely marked with black, brown, or gray stripes. This
distinctive color pattern is a type of disruptive coloration;
the stripes help to conceal a tiger in tall vegetation by visually breaking up the shape
of the body. (2)
3. Tigers can be identified by the stripe patterns on their faces and bodies, which are
unique to each tiger. Tigers may also be identified by their paw prints,
or pugmarks. Because pugmarks of the same tiger may look
different in varying soil types, only tigers with foot peculiarities can be reliably
identified by their prints. (9)
4. A tiger's underside is white or creamy, the tail is ringed, and
the ears are black with a white central spot. When one tiger threatens
another, it twists its ears so that the backs face forward, prominently displaying the
white markings. (1, 3, 14)
5. The length and thickness of a tiger's coat varies according to geographic latitude.
Tigers living in cold climates, such as Russia, grow thick, shaggy coats in winter. Tigers
in warmer climates have short, dense coats. (2)
6. Tigers with white coats are rare in the wild. White tigers are leucocystic (white with sparse coloration), having blue eyes
and gray to brown stripes. True albinos have no pigmentation. (7)
a. White-coated tigers were first observed in India around the turn of the century.
Animals having this unusual recessive trait grow faster and are larger in size than the
average yellow-colored tiger. These characteristics may have surfaced due to inbreeding in
over-hunted and fragmented populations. (7)
b. Though impressive in coloration and stature, white tigers are at a disadvantage in
the wild. White coats make it difficult for these tigers to blend into their natural
environment and conceal themselves from potential prey. They can also be seen more easily
by human hunters.
c. In 1951, the Maharajah of Rewa India captured a Bengal white tiger cub to live at
his palace. This male tiger, named Mohan, was eventually bred with a yellow-colored
female. A union with one of his yellow-colored daughters produced white offspring. (7)
d. Most white tigers in zoological parks are descendants of Mohan. Another lineage of
white tigers comes from the mating of two tigers at the Hawthorn Circus in Illinois, one
Siberian and one of unknown origin, that both carried the white-color gene. (2, 7)
7. Black or melanistic tigers have reportedly been seen
in the wild, but their existence has never been confirmed. Sightings of partially
melanistic, bluish tigers, have also been reported, but skeptics feel these were probably
orange-colored tigers covered with mud. (2)
E. Life Span
In the wild, tigers probably live about 15 years. Tigers in zoos have lived 16 to 18
years, and one Siberian tiger lived 26 years. (2)
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