During the scene with Amelia in the biology lab, Wei-Chen has an affinity to the teacher's lipstick-wearing monkey, who will not leave him alone. Wei-Chen can easily recognize that the monkey is actually a male, just as the monkey can actually recognize that Wei-Chen is a monkey himself.
Did the first vertebrates evolve during the mesozoic era? No. The 1st vertebrates appeared in the fossil record about 525 million years ago during the Cambrian Period.
Ichthyostega, one of the first land-dwelling vertebrate animals. Wikimedia Commons. Vertebrate animals have come a long way since their tiny, translucent ancestors swam the world's seas over 500 million years ago.