Andorians are tall creatures from the planet Andor, characterised by their blue skin and prominent antennae. They are the only species known that demonstrate characteristics of both mammalian and insectoid species, a unique distinction that may account for their love for beating things up. An angry Andorian, much like a Klingon, seldom turns down a fair fight, and though aggression naturally varies with the Andorian in question the Andorians have formed a reputation for being violent and wrathful, not to mention for having an exo-skeleton of sorts.
Andorians have four sexes, and although most outsiders are not aware of such niceties (the sexes can be fairly roughly divided into something resembling 'male' and 'female', and that's good enough for outsiders), the sex of an Andorian can be seen from their last name. Andorian last names starting with zh' or sh' are female, while those starting with th' or ch' are male. Again, most outsiders do not know the exact distinctions between the four sexes, and most would be pretty creeped out if they did know.
Despite being slow to anger, Andorians are not fun to get in a fight with once they are aroused. The average Andorian is a bit dim, but has endurance that an athletic human would envy without end. Andorians are usually members of the United Federation of Planets, as is the planet Andor, and in pan-Federation athletics Andorians frequently achieve great success in events of endurance.