Greylag goose the western greylag goose, breeds in Iceland and north and central Europe; "A. a. rubrirostris", the eastern greylag goose, breeds in Romania, Turkey and Russia eastwards to northeastern China. The two subspecies intergrade where their ranges meet. The greylag goose sometimes hybridises with other species of goose including the barnacle goose ("Branta leucopsis") and the Canada goose ("Branta canadensis"), and occasionally with the mute swan ("Cygnus olor"). The greylag goose was one of the first animals to be domesticated; this happened at least 3000 years ago in Ancient Egypt, the domestic breed being known as "A. a. domesticus". As the
Polyphemus (crustacean) pairs of legs with exopodites, or outer branches. The legs are adapted for catching mobile prey, generally smaller species of water flea such as young "Daphnia" and "Bosmina". "Polyphemus" has two compound eyes that are fused to form a single unit, with a zoned set of receptors. This zoned structure is paired with an eye-control system that allows the "Polyphemus" to visually distinguish target size to avoid predators and track prey. "P. pediculus" is approximately in length. "P. exiguus", while similar in morphology, is smaller. Polyphemus (crustacean) Polyphemus is a genus of water fleas, and the only genus in the