Figure 1

Fight characteristics depending on the age of ergatoid males of the ant Cardiocondyla obscurior . A) Fights were initiated more frequently by the older male when their opponent had eclosed on the day of fighting (old-d0) or was one day old (old-d1) than when the young male was two days old (old-d2). B) Biting was performed only by the attacking male when the opponent was less than one day old (old-d0), whereas both males attacked when the young male was older (old-d1 and old-d2). C) Fights were won exclusively by the older male when the rival was younger than two days (old-d0 and old-d1), yet in interactions between an old and a two-day old male, both males had similar chances of winning. Some fights resulted in the death of both males. Small italic letters indicate significance groups of the white/grey bars.