Other mistake: In the beginning of the film when you're introduced to the younger, humanoid Sil in the laboratory, an extreme close-up of her eyes and face clearly reveals the young actor's contact lenses.
Other mistake: When Sil jumps through the hotel room wall, Pres fires two shots from his Glock and then gets in the elevator. In the elevator he drops the magazine and his Glock has the slide locked back showing the magazine is empty. The man is an acknowledged expert in special ops (Indeed, the fact that he changes magazines in the elevator demonstrates his preparedness. He wants to face Sil with every bullet he can, he doesn't want to be even two short.) He is going up against an extremely dangerous extraterrestrial life form that has already killed several people. There is absolutely no way he would be carrying a weapon that was not fully loaded.
Other mistake: At the end, during the final showdown, Laura falls into the oil and it is deep enough for her to need to swim in it, but she is completely clean afterwards. Even her jeans are spotless in the next scene when they reenter the sewers and the camera is zoomed out, showing her legs.
Suggested correction: This entry is so wrong, I don't quite know where to begin. The idea that all species, without exception, have the females as the aggressors and the males as docile is absolutely one of the most ridiculous things I have ever read. It is not backed up by fact in the slightest. They also did use human DNA; they added the sample of alien DNA to it to create Sil.
The posting states that there are exceptions to the rule and specifically states "almost every species." The mistake is not that a female must be "docile". It is that a scientist professing qualifications in biology, genetics, and biochemistry would make such a stupid statement, believing it to be invariably true.
However, there are exceptions; any one species makes this possible. I will start with African Lions. In Africa, the female lions are the main aggressors.
Noman ★
Suggested correction: They never said Sil was a natural predator when they created her. She was half human and half alien and it was their belief that human females are more docile (i.e. more motherly, more gentle, more empathetic, and less aggressive than human males). Although the reply to "more docile and controllable" was "you guys don't get out much", meaning that girls aren't that docile and controllable.
Bishop73