- Common octopus is classified as a mollusk
- The typical octopus has a saccular body: the head is only slightly demarcated from the body and has large, complex eyes and a beak, and eight contractile arms
- The octopus has the useful ability to regenerate a tentacle if it loses one.
- Adults usually weigh around 15 kg (33 lb), with an arm span of up to 4.3 m (14 ft)
- They live in all the world’s oceans, but are especially abundant in warm, tropical waters.
- Most octopuses move by crawling along the bottom with their arms and suckers
- Octopuses are solitary animals who make their homes in rocks and coral or dig burrows.
- The soft body can rapidly alter its shape, enabling octopuses to squeeze through small gaps.
- The octopus can change to grey, brown, pink, blue, or green to blend in with its surroundings.
- Most octopuses swim by expelling a jet of water from the mantle through the siphon into the sea
- Octopuses feed mainly upon crabs and lobsters, although some are plankton feeders, and they are fed upon by a number of marine fishes.
- If threatened, octopuses shoot an inky fluid that darkens the water, confusing the aggressor.
- Octopuses are highly intelligent; the extent of their intelligence and learning capability are not well defined