Answer:
He meant that humans evolved from fish rather than monkey.
Step-by-step explanation:
What Prosanta Chakrabarty means when he says "...we are not monkeys. We are fish, " is that "humans evolved from fish rather than a monkey."
This is because, Prosanta Chakrabarty is an American Ichthyologist whose field is based on the study of fish its history, development, and evolution.
In one of his studies, he concluded that humans actually evolved from fish instead of the usual belief that humans evolved from monkeys.
Hence, he declared that "we are not monkeys. We are fish."