imformation of octopus eng!
imformation of octopus eng!
imformation of octopuses eng!
- 反斗才子Lv 61 十年前最愛解答
Octopus – The Great Mollusk
Also known as the ‘Devil-Fish’ due to the terror their strange appearance caused early sea-farers the Octopus or “Eight Footed” cephalopod refers to the Genus Octopi, which are members of the Phylum Mollusca of the class Cephalopoda, order and family Octopoda. Characterized by their having eight “legs” which are more accurately referred to as arms, a lack of skeletal structure and unique locomotion capabilities the Octopus is an often misunderstood and much maligned creature.
Each of the octopus’s arms have two rows of suction cups each of which has ‘taste sensors’ to allow it to identify food. With the ability to regenerate lost arms and an eye on each side of its head Octopi are hardy predators with unique self defence mechanisms and very good eyesight. They are however deaf.
Most Octopi have a globe-shaped ‘head’ or mantle that contains all the vital organs and mouth which hold a sharp beak which is used to kill and decimate prey. Their skin is smooth and ranges in color most normally from a tan to light brown with some coloration, but many are able to change colors by contracting skin cells filled with pigments to allow it to hide when hunting for prey. Some Octopi can even mimic other fish and objects, and their defensive arsenal includes the ability to squirt an ink like substance at an attacker to mask their getaway.
With life spans of approximately two years Octopus are often confused with squid, another Cephalopoda which has two longer arms called ‘tentacles’ – in an octopus all eight appendages are of a similar length and are called ‘arms’ not legs.
Living primarily in dens which provide refuge from predators including other octopi and various fish their staple consists primarily of crustaceans and molluscs such as crabs and scallops. This diet is supplemented by other bivalves, snails, fish and even other octopi. They gain access to shelled prey either by pulling it apart, biting it with their beak to break it apart or by drilling through the shell and secreting a toxin to dissolve the connective tissues.
Although difficult to maintain in captivity it is not unheard of for some people to keep them as pets, although they are very sensitive and their short life span discourages many would-be owners, as does the ability to escape from even well secured tanks due to their well known problem-solving abilities and high intelligence, which has been compared to that of an average house cat. They also are a food source in many parts of the world and some species are even bred and raised exclusively for that purpose.
A misconception is that octopi eat their own arms when stressed – but studies have show that this behaviour is caused by a virus that attacks the nervous system although stress may allow the virus to attack more readily.
There are over 160 different species of Octopus, broken into two large groups:
• Cirrata: Finned octopi that live at depths between 1,000 and 24,000 feet
• Incirrata: non-finned shallow water dwellers
Octopus have a sharp beak that it uses to crack shells and inject poisons and digestive fluids into shellfish and other prey.資料來源： http://www.octopus.com/