Why do elephants have such big ears?

The large flapping ears of an elephant are very important for temperature regulation. Elephant ears are made of a very thin layer of skin stretched over cartilage and a rich network of blood vessels. On hot days, elephants will flap their ears constantly, creating a slight breeze. This breeze cools the surface blood vessels, and then the cooler blood gets circulated to the rest of the animal's body. The hot blood entering the ears can be cooled down several degrees before returning to the body. Differences in the ear sizes of African and Asian elephants can be explained, in part, by their geographical distribution. Africans originated and stayed near the equator, where it is warmer. Therefore, they have bigger ears. Asians live farther north, in slightly cooler climates, and thus have smaller ears.

The ears are also used in certain displays of aggression and during the males' mating period. If an elephant wants to intimidate a predator or rival, it will spread its ears out wide to make itself look more massive and imposing. During the breeding season, males give off an odour from the musth gland located behind their eyes. Joyce Poole, a well-known elephant researcher, has theorized that the males will fan their ears in an effort to help propel this "elephant cologne" great distances.

What do tiger´s eat?

In the wild, tigers mostly feed on larger and medium sized animals.
Sambar, gaur, chital, wild boar, nilgai and both water buffalo and domestic buffalo are the tiger's favored prey in India.
Sometimes, they also prey on leopards, pythons, sloth bears and crocodiles.
In Siberia the main prey species are manchurian wapiti, wild boar, sika deer, moose, roe deer, and musk deer.
In Sumatra Sambar, muntjac, wild boar, and malayan tapir are preyed on.
In the former Caspian tiger's range, prey included saiga antelope, camels, caucasian wisent, yak, and wild horses.
Like many predators, they are opportunistic and will eat much smaller prey, such as monkeys, peafowls, hares, and fish.

The tiger

The tiger (Panthera tigris) is a member of the Felidae family;
the largest of the four "big cats" in the genus Panthera.
Native to much of eastern and southern Asia,
the tiger is an apex predator and an obligate carnivore.
Reaching up to 3.3 metres in total length
and weighing up to 300 kilograms.
Aside from their great bulk and power,
their most recognizable feature is the pattern of dark vertical stripes that overlays near-white to reddish-orange fur.