R

Range

The total area of a land an individual or group uses (cf. territory.)

Rhinarium

a moist, hairless pad at the end of skin at the end of a nose. This is a characteristic of prosimians, dogs, and some other animals.

Reciprocity

Tit-for-tat favor exchange. You scratch my back and I'll scratch yours. An individual may do a favor for another (e.g., watch over her infant) and the recipient returns the favor at a later date. Reciprocity is facilitated by individual recognition and long-term memory.