[namlem]

Yeah, but what was the age range they tested? If they're comparing 22 year-olds to 18 year-olds, they're still only covering a small range.

[kbenson]

Accordingly, we aimed to compare the extent to which emerging adults (late adolescence to mid-twenties) and young and middle-aged adults (late twenties to about 50) experience attraction to their cross-sex friends

From the linked paper. That's for the follow-up study.