This is interesting! Ant colonies farm them!
Bloodroot is one of many plants whose seeds are spread by ants, a process called myrmecochory. The seeds have a fleshy organ called an elaiosome that attracts ants. The ants take the seeds to their nest, where they eat the elaiosomes, and put the seeds in their nest debris, where they are protected until they germinate. They also benefit from growing in a medium made richer by the ant nest debris.
The flowers produce pollen, but no nectar. Various bees and flies visit the flowers looking in vain for nectar, for instance sweat bees in the genera Lasioglossum and Halictus, cuckoo bees in the genus Nomada, small carpenter bees (Ceratina), and bee flies in the genus Bombylius. Some bees come to collect pollen, including mining bees (Andrena), which are the most effective pollinators.
The bitter and toxic leaves and rhizomes are not often eaten by mammalian herbivores.