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.
Some of these trace fossils are as wide as four inches. Perhaps these animals did not actually breathe air, and only slimed along on land for short periods as a way of moving from pond to pond. According to scientific consensus, the first verified land animal was a one-centimeter myriapod. Present-day examples of myriapods include millipedes and centipedes. This myriapod, discovered in 2003 in Scotland and named Pneumodesmus newmani, is dated to 428 million years ago.