C r o c o d i l i e s

May 21, 2006

 crock.jpg

The word reptile  means "to crawl". Crocodiles are a member of the reptile order Crocodylia, which also includes alligators, gharials and caimans. Crocodilians are close relatives of ancient dinosaurs.

The phrase "crocodile tears" is used to describe someone who is faking sadness or remorse. A crocodile does not weep over the victim it just ate, but crocodile tears do weep over to help lubricate and clean thier eyes. Tears are especially apparent when a crocodile has been out of the water for a while and the eyes start to dry out. While underwater, a protective membrane serves as an extra eyelid. The membrance can interefere with a crocodile`s focus, so they rely heavily on hearing underwater.

combine.JPG

Crocodiles have excellent night vision due to a reflective layer of cells called tapetum. These reflector cells mirror even small quantities of light.

Crocodiles can crawl along on thier bellies or raise themselves off the ground in a high walk. They are capable of moving quite quickly and can travel considerable distances by land.

combine2.JPG

Crocodiles have five toes on their front feet, but only four toes on their back feet. Webbing on the feet between their toes helps crocodiles move quickly through water and walk more easily in mud.

Crocodiles have 60 to 70 teeth, which they lose and grow back continually.

Most reptiles (lizards, snakes and turtles) have three-chambered hearts, but crocodiles have a four-chambered heart (like birds and mammals).

Dinner time

Crocodilians are designed to be superior hunters, and many will eat just about any-thing they can catch, including people. Their teeth are ideal for grabbing and crushing prey, but not for chewing. Instead of chewing, crocodilians rip their food apart or swallow it whole. Crocodilians have a very high level of acid in their stomach to help them digest every part of an animal – even the bones. and they store more than half of energy supplied by a meal as fat in thier tails, back and abdomens. Because they can store so much energy, it is possible for  a large crocodilian to go up to two years without a meal.

Interesting facts

Crocodilians share many characteristics and lifestyles. social animals, they live in warm (tropical) climates in freshwater marshes, rivers, lakes and swamps (only the saltwater). Strong swimmers, these carnivores (meat eaters) spend much of thier time in water, but they are born on land and have lungs, not gills. Some crcodilians can stay under-water for up to 30 minutes if they have to, but a typical dive is about 15 minutes. Crocodilians are vertebrates (animals with backbones). Because they are reptiles, they are cold-blooded; thier body temperature changes with that of their enviroment.

Excellent parents

Like most reptiles, crocodilians lay eggs. Crocodilians mothers build nests and lay one  clutch of eggs a year. A clutch may consist of 15 to 80 eggs (depending on the species). The mother fiercely guards her nest, while the male stays nearby to assist her, but he will not get too close to the nest for fear of being attached himself. (Some species dig holes in the ground, others combine mud, leaves and branches and build above ground.) The sex of the babies is determined by the temperature of the eggs during the first few weeks. If the nest is below 86 F (30 C), all are females; above 93 F (34 C), all are male. Temperature in between will produce both sexes. some mothers will break the eggs by gently chewing on them. Some crocodilian parents will protect young untill they are old enough to look after themselves (about 3 months), while other crocodilian parents provide no further care for thier offspring once the younf hatch.

Alligator eggs and incubation

eggs1.JPG

An alligator may lay 50 to 60 eggs in a nest as large as 10 feet wide and 3 to 6 feet deep. The eggs are incubated by the heat of the sun and decaying plant matter. Baby alligators use a special egg tppth to break out of their shells.

Advertisements

One Response to “C r o c o d i l i e s”


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: