Fridge / Supergirl (2015) S3E11 "Fort Rozz"

Fridge Logic

• Apparently, the males of all known species appear to possess a Y-chromosome, according to the episode, since none of the human or alien males are willing to go with Kara, and all the male prisoners (of many races) aboard the station are dead. It should be pointed out that even on Earth, only mammals have the Y-chromosome. At least one of the prisoners aboard looks like his species is more closely related to reptiles though. Of course, given how very similar (even visually identical) with humans most "aliens" here are, it's not totally surprising.