Complex sentence: Unlike many Old World cuckoos, coucals are not brood parasites, though they do have their own reproductive peculiarity: all members of the genus are to varying degrees sex-role reversed so that the smaller male provides most of the parental care.
Split into simpler sentences: Unlike many Old World cuckoos, coucals are not brood parasites. On the other hand, they do have their own reproductive peculiarity: all members of the genus are to varying degrees sex-role reversed so that the smaller male provides most of the parental care.