1. The largest crocodile species is saltwater
crocodile (Crocodylus porosus), encountered from India to northern
Australia and Fiji. In can reach 7 m (23 ft) in length and 1 tonne in
weight! At 5 m (17 ft) length, it already has 0.5 tonne!
Even so, a crocodile egg is no larger than that of a goose!
The
smallest crocodile is the dwarf crocodile (Osteolaemus tetraspis) from
central Africa, which has a maximum length of 1.9 m (6.5 ft). It is more
terrestrial than other crocodiles.
2. To "cry crocodile tears"
is a common expression which is used for depicting fake sadness. It has
its origins in the myth according to which reptiles weep while eating
humans. But, believe it or not, crocodiles really do wipe while
feasting, but rather due to physiological reasons than remorse. Their
eyes can froth and bubble during the feeding. Air pushed through the
sinuses could mix with tears in the animal's lacrimal (tear) glands and
the whole content could be emptied into the eye; resulting the "fake"
remorse.
3. Crocodile skin is considered one of the finest and
best, being soft and durable. In many tribal societies, skin crocodile
is used as a symbol of high status. But only the skin on the belly has
these qualities; the back skin is covered in bones (called osteoderms)
that reflects arrows, spears and even bullets!
A crocodile skin purse can cost $ 15,000.
The value of the crocodile skin has been fueling an intense poaching and today many of the
23 species of crocodiles and relatives are threatened, many populations
being wiped out. The salvation of the crocodiles could come from the
crocodile farms.
Brazilian poachers capture caymans during the
night, by thrusting spears between their eyes (which can be easily
spotted night, due to the shiny tapetum layer). The animals are brought
into the boats and skinned alive.
4. Some populations venerated
the crocodiles (like the ancient Egyptians). From some tribes in New
Guinea, the crocodile is a totem god and those people make themselves
crocodile-like body scarring, which is an extremely painful procedure.
In
the case of Australian Aborigines, some tribes were expert in crocodile
hunt, while for others the crocodile hunt was taboo.
5. Crocodiles display increased aggressiveness during the mating season (linked to the monsoon).
6.
Each crocodile jaw carries 24 sharp teeth meant to grasp and crush, not
to chew. That's why they swallow stones that grind the food inside
their stomachs (the stomach stones also serve as ballast). The teeth are
continuously replaced along the crocodile's life. Crocodiles can exert
enormous pressure when closing their jaws, but the force for opening
them is so weak, that an adhesive band is enough to keep a large
crocodiles' jaw shut up. The powerful jaws can be extremely delicate,
working like pencils, when removing offspring from the nest. Still,
beware at the tail: it inflicts powerful blows.
7. Many times
crocodiles stay on the river banks mouth wide open. That is not an
aggressive posture, but a way to cool off: they sweat through the mouth!
8.
The crocodiles have a four-chambered heart like in birds (their closest
relatives) and mammals, for an active life. Still, when diving, the
heart behaves like a three-chambered reptilian heart, enabling them to
stay more underwater.
9. How can you make the difference between
a crocodile and an alligator? If you are not accustomed to their shape,
look at the mouth: crocodiles have a clearly visible the fourth tooth
on the lower jaw even when the mouth is closed (alligators and caymans
have a groove where that tooth fits). Because crocodiles have salt
glands inside their mouths they can stand sea water, while alligators
cannot. That's why many crocodiles species abound in mangroves and
estuaries. Behaviorally, crocodiles are more active and more aggressive
than alligators, and also less resistant to cold (alligators are found
in subtropical areas, crocodiles not).
10. If you turn on a
lantern at night in waters populated by crocodiles, you will see pairs
of shiny red dots. These are the crocodiles' eyes which have a layer
called tapetum behind their retina, containing crystals that reflect
light and make possible the night vision.
11. 99% of the
crocodile offspring are eaten in the fist year of life by large fish,
monitor lizards, herons and ... adult crocodiles. During the first weeks
of life, the crocodile offspring eats the food reserves from its
viteline sack. The crocodile eggs are appreciated by monitor lizards,
hyenas, large storks and even... humans. A female lays 20-80 eggs which
are incubated in a nest built from plant materials and defended by her
for three months.
A farmed crocodile reaches 1.5 m (5 ft) in
length in just one year. In the wild, without such a constant food
supply, it requires 3 years to reach the same length.
12.
Crocodiles can swim just with the help of their powerful tail with 40 km
(25 mi) per hour, and can stand underwater 2-3 hours. On land they can
burst on short rapid races, but they get tired very quickly. They can
also execute jumps out of the water, a several meters long.
13.
The first crocodiles appeared 240 million years ago, at the same time
with the dinosaurs (to which they are related), had less than 1 m (3 ft)
in length and ran on two feet! That's why even today, crocodiles have
longer hind limbs than fore limbs.
14. Crocodiles can live up to 80 years!
Sunday, October 7, 2012
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