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
The earliest known life forms on Earth are putative fossilized microorganisms found in hydrothermal vent precipitates. The earliest time that life forms first appeared on Earth is unknown.
