Cuttlefish jet propulsion muscle is fantastically efficient

Cuttlefish jet propulsion muscle is fantastically efficientPulling water in at the back of the mantle and squirting it out of the funnel at the front propels cuttlefish fast, but these cephalopods, which are close relatives of squid, reserve this mode of motion for dire situations.They can only sustain this form of movement for brief outbursts, when the stakes are high, because jetting is extremely costly.But why is jetting so energetically expensive?Initially, scientists thought that jetting tiny volumes of high-speed fluid was inefficient, but Nicholas Gladman and Graham Askew, from the University of Leeds, UK, recently revealed that this is not the case.So, the duo switched their attention to finding out how efficient the muscles that expel jets of water from the cuttlefish's body are, to discover why jetting is so costly.