The Javan tiger was a subspecies of tiger that was endemic to the Indonesian island of Java. In the early 19th century, Javan tigers were common pests, but as the human population increased and their habitat was destroyed for agriculture, they were ruthlessly hunted. The last confirmed sighting of a Javan tiger was in 1972, though tracks suggested a few may have survived until 1979. Habitat loss and agricultural expansion were the primary causes of their extinction.
3. Extinction is a normal process in the course of evolution. Species
have slowly evolved and disappeared throughout geologic time as
the result of climate changes and the inability to adapt to
survive competition and predation. Since the 1600s, however, the
rate of extinction has accelerated rapidly because of human
population growth and human resource consumption.
Today, most of the world's habitats are changing faster than most
species can adapt to through evolution, or natural selection. The
current global extinction rate is exponentially greater than the
background (normal rate of extinction in the process of evolution)
extinction rate. Many biologists believe that we are in the middle
of the greatest mass extinction episode since the disappearance
of the dinosaurs 65 million years ago.
4. Causes of extinction
There are a number of reasons that can contribute
directly or indirectly to the extinction of a species or
group of species. The primary causes of species
extinction or endangerment are habitat destruction,
commercial exploitation (such as plant collecting,
hunting, and trade in animal parts), damage caused by
non-native plants and animals introduced into an area,
and pollution.
The survival of ecosystems (plant and animal
communities and their physical surroundings) such as
forests, coral reefs, or wetlands depends on their
biodiversity, or variety of plants, animals, and habitats, as
well as the many interactions among these species. The
removal or disappearance of one or several species may
irreversibly damage the ecosystem and lead to its
decline.
5. JAVAN TIGER
Javan Tigers were a subspecies of tigers which were
limited to the Indonesian island of Java. In the early
19th century Javan tigers were so common, that in
some areas they were considered nothing more than
pests. As the human population increased, large parts
of the island were cultivated, leading to a severe
reduction of their natural habitat. Wherever man
moved in, the Javan tigers were ruthlessly hunted down
or poisoned. Natives carried much of the hunting out, a
surprising thing since they considered the tiger a
reincarnation of their dead relatives. The last specimen
to have been seen was sighted in 1972, although there
is evidence from track counts that the animal had
lingered into the 1980’s. The last track counts to yield
evidence of the tigers was held in 1979, when just
three tigers were identified. The leading cause of their
extinction was agricultural encroachment and habitat
loss, which continues to be a serious concern in Java.
6. Habitat and Ecology
At the end of the 18th century, tigers inhabited
most of Java. Around 1850, the people living in the
rural areas still considered them a plague. Until
1940, tigers had retreated to remote mountainous
and forested areas. Around 1970, the only known
tigers lived in the region of Mount Betiri, with an
altitude of 1,192 m (3,911 ft) the highest mountain
in Java's southeast, which had not been settled due
to the rugged and slopy terrain. In 1972, the
500 km2(190 sq mi) area was gazetted as wildlife
reserve. The last tigers were sighted there in 1976.
7. Javan tigers were very small compared to other subspecies
of the Asian mainland, but larger in size than Bali tigers.
Males weighed between 100 and 140 kg (220 and 310 lb)
on average with a body length of 200 to 245 cm (79 to 96
in). Females were smaller than males and weighed between
75 and 115 kg (170 and 250 lb) on average. They usually
had long and thin stripes, which were slightly more
numerous than of the Sumatran tiger. Their nose was long
and narrow, occipital plane remarkably narrow
and carnassials relatively long. Based on
these cranial differences, the Javan tiger was proposed to be
assigned to a distinct species,Panthera sondaica. Classically
it is considered to be a subspecies of tiger Panthera tigris.
The smaller body size of Javan tigers is attributed
to Bergmann’s rule and the size of the available prey
species in Java, which are smaller than
the cervid and bovid species distributed on the Asian
mainland. However, the diameter of their tracks are larger
than ofBengal tiger in Bangladesh, India and Nepal.