When observing an adult Tiger Swallowtail on milkweed, what is the primary biological purpose of this interaction?

Answer

It is an energy transaction to fuel the butterfly's flight and daily activities.

When an adult swallowtail feeds on milkweed nectar, it is capitalizing on a readily available energy source for immediate fuel, not fulfilling a host/offspring bond.

When observing an adult Tiger Swallowtail on milkweed, what is the primary biological purpose of this interaction?
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