Scientists study lots of stuff that seems weird but makes perfect sense to someone else. :D

I thought studying the immune systems of tunicates was weird, until I found out their immune systems have similarities to our own.

I wouldn't be so quick to pass it off as psychological. There have been some surprising studies involving human smell, pheremones, and genetics. For example, I read a study where women smelled shirts that men had worn for a couple days. The results showed that the women preferred the scent of men with complimentary immune systems (i.e., if the woman had high counts of antibodies against diseases a, b, f, h, and i, she'd most prefer a man with high antibodies counts against diseases c, d, e, and g). Seems to suggest a genetic advantage, giving offspring the highest chance at a robust immune system.

I think to be truly accurate they would need to smell blindfolded and not just mislabel the poop. All baby poop looks different and I'm sure the mothers could tell which was their baby's poop.

I've often said that if I could bottle baby smell (from their head, not their butt) and the euphoria that mother's get from it, it would outsell crack.