Among the largest species of cats in the world, tigers are powerful hunters with sharp teeth, strong jaws and agile bodies. They range across Asia from Russia all the way to Sumatra and mainland Southeast Asia. Researchers still have much to learn about these beautiful, endangered cats.
There is currently one recognized species of tiger, Panthera tigris. Scientists have further classified the tiger into nine subspecies: the extinct Bali, Caspian and Javan subspecies, and the living Malayan, Sumatran, South China, Indochinese, Bengal and Amur (or Siberian) subspecies. Of these six subspecies, AZA-accredited zoos currently manage three: Amur, Malayan and Sumatran. The Smithsonian's National Zoo and Conservation Biology Institute is home to Sumatran and Amur tigers; Sumatran tigers are listed as Critically Endangered on the International Union for Conservation of Nature's Red List, and Amur tigers have been classified as Endangered.
Tigers have reddish-orange coats with prominent black stripes, white bellies and white spots on their ears. Like a human fingerprint, no two tigers have the exact same markings. Because of this, researchers can use stripe patterns to identify different individuals when studying tigers in the wild. Tigers are powerful hunters with sharp teeth, strong jaws and agile bodies. They are the largest terrestrial mammal whose diet consists entirely of meat; the largest tiger ever recorded was an Amur tiger. The tiger's closest relative is the lion. In fact, without fur, it is difficult to distinguish a tiger from a lion. Tigers are among the largest cats in the world, and the Amur tiger is the largest subspecies with males weighing up to 660 pounds (300 kilograms) and measuring 10 feet (3 meters). Sumatran tigers are the smallest subspecies, maxing out at 310 pounds (140 kilograms) and 8 feet (2.4 meters). Female tigers of all subspecies tend to be smaller than their male counterparts.
Historically, tigers existed throughout much of Eastern and Southern Asia, as well as in parts of Central and Western Asia and the Middle East, surrounding the Caspian Sea. Their range has diminished significantly as human populations have expanded. It is believed they currently occupy just 7 percent of their historic range. Presently, tigers are found in a variety of habitats across South and Southeast Asia, China and Eastern Russia. They thrive in temperate, tropical or evergreen forests, mangrove swamps and grasslands. Amur tigers are primarily found in Far-East Russia, although there are small populations across the border into China and potentially North Korea. Sumatran tigers are found only on the Indonesian island of Sumatra. A tiger's range within these regions is determined by the availability of prey.
Elephants are the largest land mammals on earth and have distinctly massive bodies, large ears, and long trunks. They use their trunks to pick up objects, trumpet warnings, greet other elephants, or suck up water for drinking or bathing, among other uses. Both male and female African elephants grow tusks and each individual can either be left- or right-tusked, and the one they use more is usually smaller because of wear and tear. Elephant tusks serve many purposes. These extended teeth can be used to protect the elephant's trunk, lift and move objects, gather food, and strip bark from trees. They can also be used for defense. During times of drought, elephants even use their tusks to dig holes to find water underground.
Two genetically different African species exist: the savanna elephant and the forest elephant, with a number of characteristics that differentiate them both. The African savanna elephant is the largest elephant species, while the Asian forest elephant and the African forest elephant are of a comparable, smaller size.
Asian elephants differ in several ways from their African relatives, with more than 10 distinct physical differences between them. For example, Asian elephants' ears are smaller compared to the large fan-shaped ears of the African species. Only some male Asian elephants have tusks, while both male and female African elephants grow tusks.
Led by a matriarch, elephants are organized into complex social structures of females and calves, while male elephants tend to live in isolation or in small bachelor groups. A single calf is born to a female once every four to five years and after a gestation period of 22 months—the longest of any mammal. Calves are cared for by the entire herd of related females. Female calves may stay with their maternal herd for the rest of their lives, while males leave the herd as they reach puberty. Forest elephants' social groups differ slightly and may be comprised of only an adult female and her offspring. However, they may congregate in larger groups in forest clearings where resources are more abundant.
Elephants need extensive land areas to survive and meet their ecological needs, which includes food, water, and space. On average, an elephant can feed up to 18 hours and consume hundreds of pounds of plant matter in a single day. As a result, as they lose habitat, they often come into conflict with people in competition for resources.
