Gold-digging lady spiders prefer silk-wrapped gifts.
"Hi, I'm a crepuscular spider, want to mate?" Doesn't sound too enticing, does it? That's probably why male crepuscular spiders (crepuscular means "active at twilight") need to grease the wheels with a few gifts. However, any old gifts won't do: in this study, the researchers show that female crepuscular spiders prefer silk-wrapped gifts, and they will mate more with males offering these tokens. Because silk takes energy to produce, these gifts actually serve as an indication of the health of th