Good afternoon teacher and all my friends, today I would like to talk about an animal that we all know. It's an animal that is dangerous to us, but we are dangerous to them as well. They are ambush hunters, waiting for fish or land animals to come close, then rushing out to attack. As cold-blooded predators, they have a very slow metabolism, so they can survive a long period even up to a year without food. I believe all of you have an idea on which animal I'm talking about, it is crocodile.
Crocodiles can move and live on land, but they need to be close to water. Crocodiles are mostly found near salty water unlike alligators who live near fresh water.
Overall there are 23 species of crocodilians inlcluding alligators , caimans and crocodiles. Compared with many other animals, crocodilians grow rapidly. Many species increase in length at least 20 to 30 times from hatchlings, and increase in weight by at least 1,000 times within 10 to 20 years. However, growth rate varies significantly between species, and also between individuals of each species. Key factors including temperature, frequency of feeding, quality of food and even social factors can result in major differences in growth rates and hence maximum size. Size greatly varies between species, from the dwarf crocodile to the saltwater crocodile.
Dwarf crocodiles attain a medium adult length of 1.5 meters , though the maximum recorded length for this species is 1.9 meters which is slightly longer than a height of a man. Adult specimens typically weigh between 18 and 32 kg , with the largest females weighing up to 40 kg and the largest males weighing 80 kg. Larger species can reach over 4.85 metres long and weigh over 1,200 kg.
Most crocodiles can achieve speed of around 12-14 km/h for short periods, which is somewhat slower than a fit human can run. But They can swim up to 30km/h, if you meet them in the water, you are mostly dead. For a smaller species of crocodile it can live around 30-50...
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