|Scene 1a: Clearly a male on top|
|Scene 1b: RNX022 on bottom, also clearly male|
|Scene 2: RNX022 pinned to ground by another male|
A little bit later, I found RNX022 pinned on the grass by another butterfly, which could be another male. Male monarchs will force females who are not receptive to their courtship displays into mating by sitting on them! Certainly this male seemed to be performing the "take-down" maneuver. So why was RNX022 being targeted by other males as a potential mate? What cues was RNX022 sending out or failing to send out that made others mistake him for a female?
For more information on mating, see the paper
"How Often Do Males and Females Mate, and What Affects the Timing of Mating?"
Edit 09/08/12: I've been reading "The Last Monarch Butterfly" by Phil Schappert, which says that larger male may attack smaller males and that male-male interactions are common. However, these interactions are not described in the book so I still don't know if this was simply one of those interactions or if it was truly a case of mistaken identity.