Re-watching these two 1980ish science fiction classics reminded me that Sigourney Weaver not only had to fight off the terrifying alien(s), but she also had to fight off greedy corporate scientists. They wanted to capture the extremely dangerous alien organisms for research. You know, mess with their unique alien properties in test tubes, so that they could find a way to profit (while, inadvertently, putting the entire human race at risk).
Of course, in the “real” non-fictional world there is no such thing as greedy corporate scientists (willing to put our lives at risk). Why? Because it’s “Science.”