Question

can anyone ... answer .... dat why humans are so complex ???? ....

Answer 1

One reason that humans are so complex (and in turn difficult to study) is because of the property of emergence. Emergence is the reason that a reductionist view on science is not sufficient to fully explain the nature and workings of the universe, or that of humans particularly (it is however necessary, though). 

Answer 2

just to show their dominance on simpl creatures...