Octopuses are rather odd . The advanced brains of these hunters are encased in a soft , squashy body that ’s circle by eight long , flexible arms . Now , researchers lead the first kinematic analytic thinking of their arm coordination unwrap how it does n’t weigh which way their brain is pointed , they can creep in any counseling . And that ’s thanks to bare shortening and elongating movements . Thefindingswere put out inCurrent Biologythis hebdomad .
" Octopuses use alone locomotion strategies that are different from those found in other animals,“Binyamin Hochner from the Hebrew University of Jerusalemsays in anews release . " This is most potential due to their soft molluscan body that pass to the phylogeny of ' foreign ' sound structure , enable efficient locomotion control without a inflexible underframe . " amazingly , we ’re still not sure how they coordinate their “ hyper - redundant ” limb during motivity . Like us , their torso are bilaterally symmetrical , with one side being more or less a mirror simulacrum of the other ; their two eye and opthalmic lobes are locate on the sides of their head , for instance . Their eight leg , however , are radially symmetrical around their bodies – that is , evenly space , like a Proto-Indo European or an umbrella .
To visualise out how octopuses control the motion of their bodies , Hochner and colleagues immortalise TV of Octopus vulgaris crawling over objects in a tank . As they studied the footage physique - by - frame , they noticed that octopuses can cower in any charge relative to their consistency orientation , despite their bilaterally symmetrical symmetry . It does n’t count which way of life their head is face : The orientation of the physical structure and crawling direction are severally control , and their crawling lacks any clear rhythm .
The secret to their manoeuvrability fare from the stellate balance of their arms , as well as the dewy-eyed pushing - by - elongation mechanism that gives their crawling its thrust . As one leg elongates , it pushes the consistence by from where that leg tint down on the ground . With its radially symmetric legs , take a direction is as simple as choosing which legs to extend , Science explains : To move decent , unfold the legs on the left wing , and to move frontwards , stretch along the pegleg in the back .
This video shows how an octopus can crawl in any direction proportional to its body orientation course and never needs to readjust its head ( green arrow for body orientation , dark pointer for crawling direction ):
In this video , you may see how the preference of the body and crawling direction are severally control , and how its creep lack any apparent rhythmic patterns in limb coordination :
harmonise to the Embodied Organization concept , the body and its motor control strategy evolved together within the context of use of the environment . Octopuses likely evolved from clam - similar animals with a hard outer racing shell and not much movement , or a snail with its single foot . " During evolution , octopus lost their lumbering protective shells and became more maneuverable on the one hired hand , but also more vulnerable on the other hand,“saysstudy co - authorGuy Levy also of the Hebrew University of Jerusalem . " Their locomotory ability evolved to be much faster than those of distinctive molluscs , probably to compensate for the want of shell . "
TV : Levy et al./Current Biology 2015
