Komodo dragon
The Komodo dragon (Varanus komodoensis),
also known as the Komodo monitor, is a large species of lizard found
in the Indonesianislands
of Komodo, Rinca, Flores, Gili Motang,
and Padar. A member of the monitor lizard family
(Varanidae),
it is the largest living species of lizard, growing to a maximum length of 3
metres (10 ft) in rare cases and weighing up to approximately 70 kilograms
(150 lb).
Their unusually large size has been attributed to island gigantism,
since no other carnivorous animals fill the niche on
the islands where they live.[6][7] However,
recent research suggests the large size of Komodo dragons may be better
understood as representative of a relictpopulation
of very large varanid lizards that once lived across Indonesia and
Australia, most of which, along with other megafauna died
out after the Pleistocene. Fossils very similar to V. komodoensis have
been found in Australia dating to greater than 3.8 million years ago, and its
body size remained stable on Flores, one of the handful of Indonesian islands where it is
currently found, over the last 900,000 years, "a time marked by major
faunal turnovers, extinction of the island's megafauna, and the arrival of
early hominids by 880 ka [kiloannums]."
As a result of their size, these lizards dominate the ecosystems in
which they live. Komodo dragons hunt and ambush prey includinginvertebrates, birds, and mammals.
It has been claimed that they have a venomous bite; there are two glands in the
lower jaw which secrete several toxic proteins. The biological significance of
these proteins is disputed, but the glands have been shown to secrete an anticoagulant.
Komodo dragon group behaviour in hunting is exceptional in the reptile world.
The diet of big Komodo dragons mainly consists of deer, though they also eat considerable
amounts of carrion. Komodo
dragons also occasionally attack humans in the area of West Manggarai Regency where they live in
Indonesia.
Mating begins between May and August, and the eggs are
laid in September. About 20 eggs are deposited in abandoned megapode nests
or in a self-dug nesting hole. The eggs are incubated for seven to eight
months, hatching in April, when insects are most plentiful. Young Komodo
dragons are vulnerable and therefore dwell in trees, safe from predators and cannibalistic adults. They take 8 to 9
years to mature, and are estimated to live up to 30 years. Komodo dragons were first recorded by Western scientists
in 1910. Their large size and fearsome reputation make them popular zoo
exhibits. In the wild, their range has contracted due to human activities, and
they are listed as vulnerable by the IUCN. They are
protected under Indonesian law, and a national park, Komodo National Park, was founded to aid
protection efforts.
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