This might help here you go
Cat (Australia); lots of cats became feral and they reproduce very fast. They became the apex predator and the native species have no defense system for them, so the cats brought tens of species on the verge of extinction (mainly placental mammals).
Fox (Australia); became an apex predator in the lack of competition, and damages the populations of native small placental mammals.
Hair (Australia); reproduces much quicker than the native species of mammals, increased significantly in numbers, and out competes the native species for the food sources.
African bee (the Americas); much more aggressive and stronger than the native bees and systematically kills their populations.
Grey squirrel (Britain); reproduces quicker than the red squirrel, is bigger, and out competes for food, brought it on the verge of extinction.
Answer:
Any of a group of submicroscopic entities consisting of a single nucleic acid chain surrounded by a protein coat and capable of replication only within the cells of living organisms: many are pathogenic
Energy or caloric and protein needs are lower on a body weight basis in childhood than during the pre-adolescent toddler or preschool years. The protein requirement of an individual is the lowest level of dietary protein intake that will balance the losses of nitrogen from the body in persons maintaining energy balance at modest levels of physical activity.
The answer is Chordates
Most of the chordates have a symmetrical bilateral body which differentiated into head, trunk and tail
The example of chordates are parrot, penguin, horse , squirell, clown fish ( the one in finding nemo), sharks, etc