The water is evaporating and the predators would be gone. The animals diet depends on other predators. It moves to warmer area when adapting to other habitats. They seek warmers areas for shelter and hide in tight spots. The traits they would need is to live above water.
There razor sharp teeth helps them against predators. The teeth can even bite through steel. They can escape a fight by going as 50-60 mph. There teeth usually scare off prey. They use these structures by doing fight and run which biting and running away over and over again.
When it is dry season the piranha will try to eat humans or capybaras. In fact that is there diet. They sometimes forge for veggies. They will evolve to something that can live on land which is equal to more food. They could change their diet based on the storage of food left.
They find food by moving fast. There body will change by having gill that can operate above water. It would have a extra fin so they could swim much faster. It would not have feet since it is a fish. This is the locomotion of the red bellied piranha.
The red skin on the piranha and camouflage on the corals. Yes, It could camouflage in a area that had corals or something red. No, if no corals or things that are red. This is useful since they can attack animals without them knowing. This is the camouflage on the red bellied piranha.
The red bellied piranha is cold blooded. They would live best in warm areas. If the area is to cold they could swim to a war
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