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Ants

Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than 12,500 out of an estimated total of 22,000 species have been classified.[3][4] They are easily identified by their elbowed antennae and a distinctive node-like structure that forms a slender waist.Ants form colonies that range in size from a few dozen predatory individuals living in small natural cavities to highly organised colonies which may occupy large territories and consist of millions of individuals. These larger colonies consist mostly of sterile wingless females forming castes of "workers", "soldiers", or other specialised groups. Nearly all ant colonies also have some fertile males called "drones" and one or more fertile females called "queens". The colonies are sometimes described as superorganisms because the ants appear to operate as a unified entity, collectively working together to support the colony.

Elephant

Elephants are large land mammals in two extant genera of the family Elephantidae: Elephas and Loxodonta, with the third genus Mammuthus extinct.[1] Three species of elephant are recognized: the African bush elephant, the African forest elephant and the Indian or Asian elephant;[2] although some group the two African species into one[3] and some researchers also postulate the existence of a fourth species in West Africa.[4] All other species and genera of Elephantidae are extinct. Most have been extinct since the last ice age, although dwarf forms of mammoths might have survived as late as 2,000 BCE.[5] Elephants and other Elephantidae were once classified with other thick-skinned animals in a now invalid order, Pachydermata.Elephants are a symbol of wisdom in Asian cultures and are famed for their memory and intelligence, where their intelligence level is thought to be equal to that of dolphins[12][13][14][15] and primates.[16][17] Aristotle once said the elephant was "the beast which passeth all others in wit and mind."[18] The word "elephant" has its origins in the Greek ἐλέφας, meaning "ivory" or "elephant".[19]

Healthy adult elephants have no natural predators,[20] although lions may take calves or weak individuals.[21][22] They are, however, threatened by human intrusion and poaching.

Desert

A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than 400 millimetres (16 in).[1] A common definition distinguishes between true deserts, which receive less than 250 millimetres (10 in) of average annual precipitation, and semideserts or steppes, which receive between 250 millimetres (10 in) and 400 to 500 millimetres (16 to 20 in).[1][2]

Deserts can also be described as areas where more water is lost by evapotranspiration than falls as precipitation.[1] In the Köppen climate classification system, deserts are classed as BWh (hot desert) or BWk (temperate desert). In the Thornthwaite climate classification system, deserts would be classified as arid megathermal climates.

Tsunami

A tsunami (plural: tsunamis or tsunami; from Japanese: 津 波 , lit. "harbor wave";[1] English pronunciation: /suːˈnɑːmi/ soo-NAH-mee or /tsuːˈnɑːmi/ tsoo-NAH-mee[2]) is a series of water waves caused by the displacement of a large volume of a body of water, typically an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonations of underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami.[3]

Tsunami waves do not resemble normal sea waves, because their wavelength is far longer. Rather than appearing as a breaking wave, a tsunami may instead initially resemble a rapidly rising tide, and for this reason they are often referred to as tidal waves. Tsunamis generally consist of a series of waves with periods ranging from minutes to hours, arriving in a so-called "wave train".[4] Wave heights of tens of metres can be generated by large events. Although the impact of tsunamis is limited to coastal areas, their destructive power can be enormous and they can affect entire ocean basins; the 2004 Indian Ocean tsunami was among the deadliest natural disasters in human history with over 230,000 people killed in 14 countries bordering the Indian Ocean.