The fossa is the largest carnivore in Madagascar and superficially resembles an elongate cat in appearance. The tail is almost as long as the slender, muscular body, and the fossa's coat is short and reddish-brown in colour. The head is fairly small, with a short muzzle and prominent ears. Unlike other members of the Viverridae family, the fossa walks on the soles of its feet; a method of locomotion known as 'plantigrade'. The short, retractable claws also enable efficient tree climbing. One of the more unique peculiarities of the fossa is the fact that adolescent females go through a 'masculinization' phase during their development; the clitoris becomes enlarged and covered in spines thus resembling the male penis, and there is an orange secretion on their underbelly which is usually only seen in mature males.