Secondary Sexual Characteristics are elements of a creature's physiology that result from it being male or female. It is one step removed from "primary sexual characteristics" (which describes the actual reproductive organs). For example, everyone knows that only male lions have that iconic mane of fur around their neck, and that only male mallard ducks have a green head; it is one of their species' Secondary Sexual Characteristics. Many times, fictional creatures are based on some manner of Real Life inspiration, and whether or not they have noticeable sexual dimorphism corresponds to whatever inspired them — if one author decides to call a lion a Smeerp, it makes sense that male Smeerps might have thick manes while female Smeerps do not, right? Now a full discussion of these characteristics is well beyond the scope of this wiki; but when this subject arises in fiction, it can manifest itself in a variety of ways.
Secondary Sexual Characteristic Gender Clues
Other Gender Clue Tropes
Tropes That Get the Secondary Sexual Characteristics of Animals Wrong
No Real Life examples, please. Please only list fictional examples that aren't listed in any of the tropes listed here. Anything that fits in any of the tropes listed should be listed in that trope.