It's flowers and diamonds for us humans, but the gift that will get male nursery-web spiders some lovin' from potential mates is chewed-up body parts. Ah, love!

Nothing says love like chewed-up body parts—at least for nursery-web spiders (Pisaura mirabilis). In some populations of these European arachnids, females won't mate with males unless the suitors present a gift of dead insects wrapped in silk. Males carry their bundles as they search for mates ...

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See also: 30 Strangest Animal Mating Habits, a Neatorama classic!