The winner takes it all: offspring of clonal crayfish follow unfamiliar dominant females rather than their own mothers

Animals have evolved sensory mechanisms that facilitate offspring recognition. The care of unrelated offspring is an example of resource take an advantage. The investment into brood care can be subject to exploitation if parents adopt offspring of other parents. Here we present evidence that the offspring of a clonal invertebrate (the marbled crayfish Procambarus virginalis ) are adopted by another mother, the winner of a combat between two mothers. We found that the offspring can distinguish between familiar and unfamiliar relatives but, after a fight, the clutches of the interacting mothers only chose the dominant female while the subordinate mother was ignored by her offspring. We conclude that the impact of sensory cues indicating maternal bond (e.g. brood pheromone) was outweighed by cues indicating visual promixity and/or dominance of females.