 Only males possess horns, whose maximum recorded length is 188 cm (74 in). Horns appear as cream-coloured nubs at around six months and start growing in a spiral pattern, reaching full growth by two years. The horns have only one or two spirals, though a few males have been reported to have two-and-a-half turns. The final form might vary in different males – the horns could form well-defined spirals, or could diverge in a structure similar to a lyre, resembling the horns of an impala, but with the final spiral incomplete. Growth rings are visible on the horn sheaths, but the annual patterns might be difficult to comprehend. Though the horns might wear out with age, the cream colour of the tips persists.
