Amazonians found the arapaima, one of the world’s largest freshwater fish, in the Amazon river basin. This fish can grow to be three meters long and weigh up to 200 kilos (440 pounds). It can survive in water with low oxygen levels by staying out of the water for a day and breathing air. Fish, birds, lizards, and other small creatures are among its favorite foods. It can crush them with its toothy tongue. This evolutionary miracle, according to scientists, has an even better trick: its scales, which have been compared to a bullet-proof vest, defend it against piranha attacks. The US Air Force has taken notice of the strong but flexible qualities of its scales. The arapaima population began to decline in the 1990s as a result of overfishing and illegal fishing. Because of this, the arapaima became endangered in parts of the Amazon. But this is no longer the case, thanks to the efforts of environmentalists and local communities during the previous two decades.