Male ruff colour as a rank signal in a monomorphic-horned mammal: behavioural correlates

摘要: Coexistence of individuals within a social group is possible through the establishment hierarchy. Social dominance achieved aggressive interactions, and, in wild sheep and goats, it related mainly to age, body size weapon as rank signals. Adult male Himalayan tahr are much larger than females subadult males. They have prominent neck ruff, ranging colour from yellow (5.5–9.5 years old, i.e. young adults, golden males) brown (7.5–14.5 older individuals, pale dark males), with males being most dominant. We investigated behaviour analysed relationships between ruff colour, courtship agonistic patterns during rut. Colour classes varied their use several (male dominance: approach, stare, horning vegetation; courtship: low stretch, naso-genital contact, rush). Golden-ruffed used more threats darker ones. Pale addressed significantly often lower or own classes, respectively, whereas ones all including own. The dominant was characterised by assertive rush, that subordinates did not. Ruff may evolved signal, homologous horn goats.