Welcome to the latest installment of “Writer Fuel – cool real-world stories that might inspire your little writer heart. Check out our Writer Fuel page on the LimFic blog for more inspiration. Today:
Octopuses are famous for their eight sucker-covered arms, whereas squids, from giant Architeuthis dux to the appetizer-size critters served at restaurants, swim with even more appendages: eight arms and two tentacles. So, what’s the difference between these different types of boneless limbs?
Squids, octopuses and their hard-shelled nautiloid relatives are all big-brained members of the class Cephalopoda. With the exception of ancient nautiloids, all living cephalopod species fall under the category of either eight-legged Octopodiformes or 10-legged Decapodiformes, and have muscular, sucker-laden arms. However, only squids, cuttlefish, bobtail squids and other members of Decapodiformes have tentacles, and only vampire squid sport stringy appendages called filaments, according to a paper published in 2017 in the Journal of Molluscan Studies. The difference between all of these cephalopods’ limbs, it turns out, largely comes down to shape and sucker placement.
“The basic difference is arms have a line of suckers going down them, whereas tentacles don’t have suckers until you get to the tentacular clubs, which are the kind of large part at the end,” Morag Taite, a postdoctoral research associate at Aberystwyth University in Wales, told Live Science.
