Exam 15: Parental Care and Mating Systems

Kirk's dik-dik (Madoqua kirkii) is a very small African antelope that forms monogamous bonds that last for years, during which time the male prevents other males from knowing when the female is in estrus. The males appear to be absolutely faithful to their mates. They appear to practice monogamy because

Baeza (2008) studied a symbiotic shrimp (Pontonia margarita) that lives inside the mantle cavity of the pearl oyster (Pinctada mazatlanica). One of his findings was that body sizes of shrimp and host oysters were closely correlated, suggesting that particular associations are long lasting. These data were consistent with social (and perhaps, genetic) monogamy in the shrimp. What other aspect(s) of the shrimps' life style would support that conclusion?