There are aliens amongst it is just that we don't call then 'aliens'

Octopuses are the closest we can come, on earth, to knowing what it might be like to encounter intelligent aliens.

The octopus threatens boundaries. Its body, a boneless mass of soft tissue, has no fixed shape. Even large octopuses – the largest species, the Giant Pacific, has an arm span of more than six metres and weighs a hundred pounds – can fit through an opening an inch wide, or about the size of its eye. This, combined with their considerable strength – a mature male Giant Pacific can lift thirty pounds with each of its 1600 suckers – means that octopuses are difficult to keep in captivity. Many octopuses have escaped their aquarium tanks through small holes; some have been known to lift the lid of their tank, making their way, sometimes across stretches of dry floor, to a neighbouring tank for a snack, or to the nearest drain, and maybe from there back home to the sea

If terror were the object of … creation, nothing could be imagined more perfect than the...

Octopuses do not have any stable colour or texture, changing at will to match their surroundings: a camouflaged octopus can be invisible from just a few feet away. Like humans, they have centralised nervous systems, but in their case there is no clear distinction between brain and body. An octopus’s neurons are dispersed throughout its body, and two-thirds of them are in its arms: each arm can act intelligently on its own, grasping, manipulating and hunting

 In evolutionary terms, the intelligence of octopuses is an anomaly. The last common ancestor between octopuses on the one hand, and humans and other intelligent animals (monkeys, dolphins, dogs, crows) on the other, was probably a primitive, blind worm-like creature that existed six hundred million years ago. Other creatures that are so evolutionarily distant from humans – lobsters, snails, slugs, clams – rate pretty low on the cognitive scale. But octopuses – and to some extent their cephalopod cousins, cuttlefish and squid – frustrate the neat evolutionary division between clever vertebrates and simple-minded invertebrates. 

Octopuses  are sophisticated problem solvers; they learn, and can use tools; and they show a capacity for mimicry, deception and, some think, humour. Just how refined their abilities are is a matter of scientific debate: their very strangeness makes octopuses hard to study. Their intelligence is like ours, and utterly unlike ours. 

The alienness of octopuses, provides an opportunity to reflect on the nature of cognition and consciousness without simply projecting from the human example. Because of their evolutionary distance from us, octopuses are an ‘independent experiment in the evolution of large brains and complex behaviour’. Insofar as we are able to make intelligent contact with them – to understand octopuses and have them understand us – it is ‘not because of a shared history, not because of kinship, but because evolution built minds twice over’. The potential worry is that the evolutionary chasm between us and the octopus is too great to make mutual intelligibility possible. In that case the octopus will have something to teach us about the limits of our own understanding.

On a more hunorous note if you cannot open the pot of jam because you cannot prise of the lid call in the Octopus