After While, Crocodile!
The toothy-grinned Nile crocodile is a distinctive creature of the Nile valley. This species of crocodile, found in hot, steamy areas of Africa, spends the majority of its days basking along river banks with its mouth wide open. Mouth gaping is similar to the panting of a dog; it helps a hot croc cool off. Mouth gaping also seems to be an invitation to the Egyptian plover, or crocodile bird, to clean the croc's teeth! Just how do crocs survive in the African sun? Like other reptiles, the Nile crocodile is ectothermic. If the temperature is high, the Nile crocodile slips into nearby water, but if the air's cool, the croc sunbathes on a riverbank to warm up. Its rough, scaly, water-tight skin prevents dehydration on land, as well as loss of body salt when in water. During the dry season, crocs travel considerable distances on land in search of water.

No Trespassing!
As far as reptiles are concerned, crocodilians are tops when it comes to parenting. These reptiles provide the most parental care for their offspring. The female lays her eggs in a carefully dug hole in the sand and mud on lake or river shores. For the next three to four months she closely guards the nest, viciously attacking any intruder, such as the egg-loving Nile monitor. When the young are ready to hatch they make a chirping sound from the buried eggs. The female then gently digs up and breaks open the eggs with her mouth-releasing the 30 cm (12 in. ) long babies. The hatchlings even get a free ride into the water. Mama croc scoops them up in her mouth and carries them in her gular pouch to the river. She will guard her babies for over a year after they've hatched. Even though a female croc is a force to be reckoned with, many smaller crocodiles fall prey to animals such as marabou storks, herons, ibis, turtles, and catfish. Less than two percent of all Nile crocodile eggs hatch and grow to maturity.

Prehistoric Or Advanced?
Crocodiles have not changed much over the last 200 million years. However, that does not mean that crocodiles are not advanced reptiles. Unlike other modern reptilians, crocodilians have efficient four-chambered hearts like mammals. Their gular pouch blocks water so that they can eat prey under water as well as on land. Their clawed feet help them be excellent climbers and vertical pupils that open wide in low light make them formidable nocturnal hunters.

That's not all. Crocs also have behavioral adaptations that make them more advanced than snakes, lizards, or turtles. They are social animals that work in groups to dig tunnels to cool off, and they care for their young.

Crocs Are Crucial
It is important to realize that the Nile croc is vital to the riverine ecosystem. They have 66 sharp teeth that make them a top predator in the food chain, help them to scavenge, and to eat barbel catfish. If crocs were to vanish from the ecosystem, the barbel catfish population could multiply enough to upset the balance of the ecosystem. The catfish have voracious appetites and could wipe out other fish species that are food sources for over 40 different types of birds. The birds are needed because their droppings recycle nutrients back into the system. Crocs are also scavengers that feed on dead carcasses found along waterways, effectively cleaning up the habitat. Without crocodiles, the Nile River and other freshwater areas in Africa risk becoming watery deserts.

There are few predators willing to tackle an adult Nile croc other than another croc or people. And people have overhunted them for their meat, skins, and other body parts. Agriculture and urban development along the Nile have encroached on the croc's habitat and completely changed parts of the river basin. Human impact has made much of the wetlands unsuitable for its original inhabitants, endangering many species as well as the crocodile. Although it is still endangered throughout much of its domain, public awareness means hope.

Dehydration: loss of water from the body