Tigers
Tigers are large, powerful cats native to various regions of Asia, recognized for their striking orange and black striped fur. As apex predators, they primarily inhabit jungles, forests, tundra, mountains, and swamps in countries like India, China, and Indonesia. With a gestation period of about four months, female tigers typically give birth to litters of two to five cubs, which remain dependent on their mothers for up to three years. Tigers are solitary hunters, marking vast territories that can range from ten to over four hundred square miles, and they are capable of taking down prey that weighs between 440 to 2,000 pounds.
Despite their iconic status, tigers are endangered largely due to habitat loss, poaching, and human-wildlife conflict. Conservation efforts have shown some success, with wild populations increasing from approximately 3,200 in 2010 to over 5,500 in 2023. However, threats remain, including illegal trade and loss of habitat. The complexity of tiger subspecies, which include the Bengal and Siberian varieties, is a topic of ongoing debate among scientists. With a unique combination of physical adaptations and behaviors, tigers play a crucial role in their ecosystems, and their survival continues to depend on effective conservation measures.
Tigers
- The tiger is a species of large cat native to parts of Asia. Tigers are well known as powerful apex predators and for their distinctive, typically orange and black striped fur. However, despite their iconic status in human culture, they are endangered due to habitat loss and other pressures.
Quick Facts
- Classification:
- Kingdom: Animalia
- Subkingdom: Bilateria
- Phylum: Chordata
- Subphylum: Vertebrata
- Class: Mammalia
- Subclass: Theria
- Order: Carnivora
- Suborder: Feliformia
- Family: Felidae
- Genus and species: Panthera tigris
- Subspecies: Disputed, but commonly includes P. t. tigris (Bengal), P. t. altaica (Siberian), P. t. amoyensis (South China), P. t. balica (Bali), P. t. corbetti (Indochinese), P. t. sondaica (Javan), P. t. sumatrae (Sumatran), P. t. virgata (Caspian)
Geographical location: Asia, specifically India, Thailand, Manchuria, China, and Indonesia
Habitat: Jungles, forests, tundra, mountains, and swamps
Gestational period: 3.5 to 4 months
Life span: Up to fifteen years in the wild, up to twenty years in captivity
Special anatomy: Sharp canine teeth, sagittal crest
The ancestors of modern tigers were members of the Felidae family of big cats that lived in northern Asia during the Late Pleistocene epoch. They migrated south and east and evolved into specific types of larger tigers according to their habitats. (The ancient saber-tooth tigers are not directly related to modern tigers.) Traditionally, scientists recognized eight or nine tiger subspecies that survived beyond the Pleistocene. Three of these populations—the Bali, Caspian, and Javan tigers—became extinct during the twentieth century due to hunting and habitat loss. The taxonomy of tiger subspecies is widely debated, however, with some studies suggesting just two extant categories: P. tigris tigris and P. tigris sondaica.
Anatomy
Tigers range in weight according to their subspecies (or population) and gender. Sumatran male tigers are the lightest, weighing 110 kilograms (250 pounds). Females weigh approximately twenty kilograms less. Siberian male tigers weigh as much as 225 kilograms (500 pounds). The heaviest known tiger weighed 465 kilograms (1,025 pounds). From head to the base of the tail, tigers measure from 1.4 to 2.8 meters (4.5 to 9 feet) long, and their tails are from 90 to 120 centimeters (3 to 4 feet). They use their tails to balance and to communicate.
Tiger skulls have a big sagittal crest which anchors a large jaw muscle. Tigers’ vertebra and joints are flexible. Their hind legs are longer than their front legs, providing impulsion and assisting leaping when they are chasing game. They have five toes on their front paws and four toes on their hind paws. Each toe has a retractable claw which is 80 to 100 millimeters (3 to 4 inches) long and helps them restrain prey and climb trees.
Mature tigers have thirty teeth. The canine teeth are 75 to 90 millimeters (2.5 to 3 inches) long. Tigers have triangular, erect ears set atop broad skulls, with their eyes positioned on the front of their face. Tigers’ eyes have reflecting retinas which enable excellent night vision. Tigers’ sense of smell is also acute; they can distinguish different animals by smell and exhibit the flehmen response.
Tigers have nineteen pairs of chromosomes, which determine genetic patterns. Their coats are colored shades of orange, with black or brown stripes of varying widths and lengths and white accents around the eyes, ruffs, and other body parts. Rarely, Bengal tigers with the two necessary alleles are born with a white foundation coat and blue eyes. They are not albinos or a separate subspecies. Tigers’ stripes vary according to subspecies, with Sumatran tigers having the most and Siberian tigers having the fewest. Each tiger’s stripes are unique and function as camouflage. Fur thickness varies with seasonal changes and geography. Siberian tigers have almost twice the number of hairs per square centimeter than Sumatran tigers.
Behavior
Tigers are solitary, preferring to hunt alone. A male tiger’s territory averages twenty-six to seventy-eight square kilometers (ten to thirty square miles), depending on the availability of prey. Some Siberian tigers roam territories of 1,036 square kilometers (400 square miles). Tigers’ territories often overlap, with several females sharing territorial space with one male. Tigers scratch on trees, leave fecal droppings, and spray urine to mark their territory. Male tigers occasionally fight. Tigers have several vocalizations to communicate aggression and receptiveness to other tigers.
Females attain sexual maturity at age three and males at age four. After a four-month gestation, females have litters of two to five cubs which are born blind and are vulnerable to predators such as pythons. The cubs drink their mother’s milk for two months, then feed at her kills until they are about two to three years old and capable of hunting alone.
Tigers can catch and kill prey as large as 160 to 900 kilograms (440 to 2,000 pounds). They stalk and ambush ungulates, knocking prey to the ground and biting the neck or throat to sever the spinal cord or suffocate the animal. Tigers can consume twenty to twenty-five kilograms (sixty to seventy pounds) of meat daily. They drag carcasses into vegetated areas and gorge on a kill, then fast. Tigers also eat termites and snakes. Some tigers, especially in the Sundarbans river delta of India and Bangladesh, have attacked and killed humans.
Conservation
Adult tigers are hunted by poachers for their hides, bones, teeth, and body parts or for sale to exotic pet traders. Much of their jungle habitat has been destroyed during wars or for agricultural use. As a result, the wild tiger population declined steadily through the twentieth century and into the early twenty-first. Conservation efforts have seen some success, with the estimated total wild population increasing from about 3,200 in 2010 to over 5,500 in 2023, according to the World Wildlife Fund. Tiger censuses have been taken by counting pugmarks in known tiger habitats. However, deforestation, habitat destruction, and poaching remain major threats to wild tiger populations, and certain populations have continued to decline.
Authorities estimate that thousands of other tigers are kept as exotic pets in North America and in zoos, sanctuaries, and circuses. Many of these are bred commercially and with little regulation, especially in China, which conservationists have identified as a significant obstacle to wild recovery programs as they encourage illegal trade. Accredited conservation breeding programs, meanwhile, aspire to preserve and increase the tiger population. In captivity, tigers can also produce hybrid offspring: ligers come from lion fathers and tiger mothers, while tigons are produced by tiger fathers and lioness mothers.
Principal Terms
alleles: alternate forms of genes
digitigrade: walks on toes
flehmen: lip movement when certain mammals, notably horses and cats, detect an unusual scent
pugmarks: paw prints
sagittal: bony skull top
Bibliography
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