Whether you're looking for brain or brawn, you can't go wrong with an octopus. Octopuses' amazing ability to jet-stream away from danger (by expelling water through a funnel tube) is coupled with an equally amazing intelligence. In labs, these invertebrates have demonstrated the ability to solve mazes and other puzzles. They have also been known to break out of aquariums in search of food and have even boarded fishing boats and opened holds to eat crabs.  As a means of stimulating their cognition and natural hunting abilities, aquariums will often provide them with problems to solve such as opening a jar to obtain the food inside.

The Giant Pacific Octopus is probably the largest octopus species although there are one or two other species in contention. One was recorded at 71 kg (156.5 lb); however, typically adults weigh around 15 kg (33 lb) with an arm span of up to 4.3 m (14 ft).

Octopuses prey upon shrimp, crabs, scallops, abalone, clams, and fish by capturing them with their suckers and then crushing them with their tough “beaks” of chitin. When necessary they can also emit a poison from their salivary glands to stun prey. There is also strong evidence that they can capture and consume sharks.

The female lays up to 100,000 eggs and diligently cares for them for many weeks until they are hatched.  Once hatched, they are extremely small and only a few survive to adulthood due to many predators.  Their average life-span is only about three to five years in the wild, which is relatively short for an animal its size. Octopuses often fall prey to other marine animals such as harbour seals, sea otters, sperm whales and large fish such as halibut and lingcod.  Humans also capture them for food, for display in aquariums, and for use as bait for other fisheries.

Octopuses have a number of adaptations which help them survive.  Their skin colour can change to blend with the background and they tend to hunt at night, which accentuates their camouflage ability. Although unable to hear, they have excellent sight, smell, and taste. The lack of skeleton allows them to hide in inconspicuous spots. When they sense danger, octopuses have a number of strategies at their disposal - including ejecting a slimy, black ink to act as a screen from predators, or contracting the mantle muscles to expel water through a funnel tube to jetstream away from the menace. 

Threats to octopuses:  Climatic changes may affect the availability of octopus food sources and, thus, may influence their range of habitat.  Octopuses are also sensitive to water pollution which may affect their survival over time.