D. iulia larvae feed on Passiflora plants almost exclusively, specifically those of subgenuses Astrophea (also known as Passiflora), Polyanthea, Tryphostemmatoides, and Plectostemma.

As adults, male and females feed differently based on their reproductive needs.
As mentioned further down, males engage in mud-puddling behavior in order to gain valuable minerals for their spermatophores.
They have also been seen to agitate the eyes of caimans and turtles in order to produce tears that the butterflies can drink.
 Observations of this from points 1500 km apart, were probably the first time scientific observations were coordinated via films broadcast on terrestrial television.

Females, meanwhile, besides visiting certain flower species for their nectar – like Lantana and Eupatorium (as both male and female D. iulia butterflies do) – also use pollen from flowers to gain nutrients needed for egg production.
D. iulia larvae feed on Passiflora plants almost exclusively, specifically those of subgenuses Astrophea (also known as Passiflora), Polyanthea, Tryphostemmatoides, and Plectostemma.
As adults, male and females feed differently based on their reproductive needs. As mentioned further down, males engage in mud-puddling behavior in order to gain valuable minerals for their spermatophores. They have also been seen to agitate the eyes of caimans and turtles in order to produce tears that the butterflies can drink.  Observations of this from points 1500 km apart, were probably the first time scientific observations were coordinated via films broadcast on terrestrial television.
Females, meanwhile, besides visiting certain flower species for their nectar – like Lantana and Eupatorium (as both male and female D. iulia butterflies do) – also use pollen from flowers to gain nutrients needed for egg production.
Dryas iulia