Species (1995)

Factual error: Fitch, who professes qualifications in biology, genetics and biochemistry, says that they made Sil female because she's a natural predator and so she'd be more docile. He should retake his finals. In every single species of predator on earth - every single one - the females are the hunters, aggressors and killers. The males may be socially dominant but they are the 'docile' ones. There are no exceptions - and no human DNA was used to create Sil - they used synthetic DNA based on the instructions transmitted to them.

Factual error: At the end when the oil in the cavern is burning there is no sign of smoke. With a fire as large as it appears to be, everyone in there should be choking to death, yet they don't even seem the least bit bothered. Forest Whitaker should have also been roasting over the flames, yet he is unscathed.