Thursday, August 13, 2015

All Hail, the Intelligent Octopus

Pacific striped, credit: The Independent
Scientists have decoded the genome of the octopus. In doing so they have discovered just how different the intelligent, eight-armed creature is. The intelligence of the invertibrate evolved much earlier than other "higher" vertebrates according to its genome. It contains 2.7 billion pieces of code, and hundreds of genes unique to the species. Some are related to the octopus' ability to change shape and color of its skin as a form of active camouflage. One British zoologist was so enthusiastic about the findings, he called the cephalopod "an alien". There is no doubt, however, that it evolved on this planet some 400 million years ago, about 230 million years before mammals, considered to be the most advanced animals living now. The octopus is Earth's first intelligent creature. A notable expansion of the octopus genome are the genes known as protocadherins, essential to developing nerve cells and their interconnections. Octopus have 168 of these, 10 times more than other invertebrates and twice as many as mammals.

These genes allowed the octopus to evolve an advanced and complex nervous system that helped it survive the ages. Its arms have there own neurons that work independently from the brain, plus huge optic lobes that make it a superb predator. An example of the octopus advanced hunting techniques is exhibited by the larger Pacific striped octopus that stalks prey close enough to tap it on the opposite side of its body with a smart tentacle. [video] This 'tap of doom' startles the prey, usually shrimp, directly into the octopus' waiting arms. Pacific striped octopus also have another interesting behavior. Most octopus have sex at a distance since the females become cannibalistic, but not the Pacific striped. These mating couples enjoy full frontal encounter with sixteen arms grasping each other sucker to sucker, beak to beak, in what scientists describe as "rough sex"!

mating, credit: R.Caldwell
Understanding how the octopus differs from its fellow cephalopods--squid, cuttlefish and nautilus--will help scientists understand what it means to be an octopus, genetically speaking. Unlike other cephalopods, they are protected by UK animal testing regulations in recognition of their obvious intelligence, dexterity and communication skills. Whether the octopus has a garden under the sea remains to be seen. They do seem to like cameras, however.