Crocodiles are believed to be among the oldest living things on Earth, having existed for about 240 million years. Throughout human history, crocodiles have been regarded by many cultures as a symbol of “power”, “fertility” and “power”. In nature, crocodiles play an important role in maintaining the balance of ecosystems. Most crocodiles live in freshwater watersheds and clean up waterways to provide a good environment for other species. Today, let’s learn about this “living fossil” of the animal kingdom.
What is the difference between
Crocodiles and alligators are often lumped together, but there are differences. First, the shape of the snout is different. The snout of the crocodile is narrow and slender, v-shaped. Alligators have a fuller, u-shaped snout.
Second, the tooth structure is different. When an alligator’s snout is closed, the fourth, longer tooth is exposed, whereas when an alligator’s snout is closed, no teeth are visible.
In addition, the range of activities is different. Alligators are mainly distributed in some parts of the United States and eastern China, among which the Chinese alligator is the only alligator distributed in China, and it is also a national priority protected wild animal. Crocodiles have a wider range and are found in Africa, Australia, Asia, North America, South America and Central America.
There are 13 different species of crocodiles, the largest of which is the saltwater crocodile, the largest reptile in the world. Saltwater crocodiles are widely distributed in northern Australia, eastern India and Southeast Asia.
In Australia’s Northern Territory, about 100,000 saltwater crocodiles inhabit coastal rivers, wetlands, open ocean and island shorelines. They are also found in India and Southeast Asia.
Adult male saltwater crocodiles can grow to more than seven meters long and weigh up to a ton. With strong jaws and sharp teeth, saltwater crocodiles have a bite force of up to 1,700kg, making them the largest in the animal kingdom. Saltwater crocodiles have rapid tooth growth and short tooth replacement cycles, requiring tooth replacement every three to six months.
The smallest member of the crocodile family is the pygmy crocodile, which is found mainly in the rainforests and mangrove swamps of central and western Africa. Compared to saltwater crocodiles, pygmy crocodiles are tiny, measuring less than 2 meters in length and weighing between 18 and 32 kilograms.
Close family ties
Female crocodiles vary in egg production and gestation length. Female crocodiles range in gestation from one to five months and lay between 10 and 100 eggs. In the case of saltwater crocodiles, females lay about 50 to 60 eggs and hatch in at least 114 days.
After laying the eggs, the female crocodiles look for a riverside nest or beach to house the unhatched baby crocodiles and guard the eggs nearby to protect them from predators. On hatching day, when the hatchlings emerge, the female grabs them in her snout and carries them to the water. A female crocodile can carry up to 19 babies at a time by her snout.
A baby crocodile lives with its mother after birth. Different kinds of crocodiles have different habits. Female Cuban crocodiles live with young crocodiles for half a year, while Nile crocodiles live with young crocodiles for weeks.
Female crocodiles communicate with their young, using specific calls to call each other. A study by Professor Nicolas Matvan of the University of Lyon in France has shown that female crocodiles are very sensitive to cries for help from their young. When pre-recorded cries for help were played, female crocodiles were more aggressive. When the recording is turned off, the attack stops.
In fact, even with the care of a female, the baby crocodiles face many dangers. Predators, including crabs, fish, snakes, lizards, sharks, anacondas, and big cats, can all pose a threat to the young crocs’ survival. Only a few crocodiles live long enough to breed. Saltwater crocodiles, for example, only about 1% of them make it to 12 years of age.
The length of life of an adult crocodile also depends on the species. Saltwater crocodiles can live for more than 70 years, while pygmy crocodiles live for about 40 to 50 years.
Crocodiles are carnivores at the top of the food chain in nature, mainly feeding on mammals, fish, mollusks, crustaceans, amphibians, reptiles and insects. Crocodiles can swim very fast, with short bursts of power up to 12 to 15 miles per hour, and can hold their breath underwater for up to an hour.
Crocodiles are often called “ambush hunters”. Crocodiles are good at waiting, and when an animal approaches the shore, they come out of the water and attack quickly. Crocodiles are undaunted by the size of their prey and will attack lions, sharks, cows or humans if they stray into their territory.
The only animal that survives a crocodile is the Egyptian plover. Egyptian plovers are symbiotic with Nile crocodiles, which feed on the remnants of their mouths and seem to enjoy the free toothpicking service.
The crocodile hunt
Guardians of the ecological environment
Crocodile is an indispensable part of the ecosystem, which plays an important role in regulating and balancing the number of other species and preventing ecological degradation.
The act of digging holes to build nests creates habitat for other animals. During the dry season, the presence of crocodiles also prevents land animals from drinking limited water resources, effectively protecting the stability of aquatic ecosystems.
Crocodiles to be consumed
Increasing consumer demand for crocodile skin products (mainly bags and shoes) in the 20th century led to the near extinction of many crocodile species, including the Orinoco, Siamese and saltwater crocodile. Some countries and regions have taken protective measures to ban commercial use of crocodiles.
Sadly, the plight of crocodiles has not improved. Crocodiles are still bred in large numbers in captivity around the world, and their skins and meat are traded commercially. In addition, human activities, habitat loss, climate change and other factors threaten the survival of wild crocodiles.
The plight of crocodiles is a microcosm of how some wild animals have gone extinct without us even knowing it. Reduce some unnecessary needs, a more sustainable development attitude. To protect wild animals is to protect ourselves.