Dutch scientists have solved the secret of the swordfish’s speed: a gland in its forbidding nose produces go-faster oil.

John Videler, emeritus professor of bionics at Groningen University, told the Volkskrant that he discovered the oil-producing gland when studying the beast at night with MRI scans.

His research, conducted 10 years ago, has just been published in the Journal of Experimental Biology. Using equipment at UMC Groningen hospital – which they freshened up afterwards with forest-scented air spray – he and his students found that the gland was connected to capillaries transporting oil to pores.

‘The oil is distributed from the pores over the front part of the head,’ says the research abstract. ‘The oil inside the gland is identical to that found on the skin and is a mixture of methyl esters. We hypothesize that the oil layer, in combination with the denticles [tooth-like protrusions on the skin], creates a super-hydrophobic layer that reduces streamwise friction drag and increases swimming efficiency.’