Domestic Dog

• GeneralIt was the first animal domesticated by humans, between 15,000 and 30,000 years ago, from the grey wolf.
• The bloodhound can have as many as 300 million scent receptors, compared with 5-6 million in humans.
• It can follow the direction of a person's gaze and pointing finger, a communicative ability that hand-reared wolves do not develop.
• It is the only animal domesticated before agriculture: it happened when we were all hunter-gatherers, and that is why its relationship with us is the oldest of all.
• It descends from the grey wolf, but not from any living wolf population: modern dogs and wolves are sister lineages that diverged from an ancestral population that has since disappeared.
• It is the mammal species with the greatest variation in size and shape: from the Chihuahua to the Great Dane the difference in weight is more than fiftyfold, something found in no other species.
• It can digest starch, unlike the wolf, thanks to additional copies of the amylase gene: an adaptation to eating the leftovers of our agricultural diet.

Skeleton type

Vertebrate - internal bony skeleton (mammal)

Habitat and environment

Lives alongside humans on every continent, including Antarctic bases

Sexual maturity

6-12 months

Gestation / incubation

63 days

Litter / clutch size

6

Life expectancy in captivity

20

Sources consulted: https://es.wikipedia.org/wiki/Canis_familiaris