'Should we presume these odd-looking creatures were designed by a mischievous god who had some time on her hands? Rummaging through a box labelled “spare parts”, she finds a horse’s head and, feeling a desire for experimentation, places it on top of the pouched torso of a kangaroo.' Photograph: Georgette Douwma/Getty Images
'Seahorses don’t live in crowded neighbourhoods, possibly because their plankton food is too scarce to support more than a handful of adults in a habitat the size of a tennis court.' Photograph: George Grall/Getty Images/National Geographic
'The seahorses greet each other with a nose-to-nose caress and, wrapping their tails around a single blade of grass, they begin a seductive dance, spiralling round and round each other. Blushes of orange and pink give away their emotions and, for a moment, the seahorses swim together, heads tucked down, tails entwined.' Photograph: Norbert Wu/ Norbert Wu/Science Faction/Cor
'The couple halt in the open water column and hold their bodies close, forming a heart shape with their touching snouts and bellies. Their first attempt isn’t quite right, so they break apart and try again several times until their position is perfected, the female just above the male. Then an extraordinary thing happens. A short hollow tube emerges from the female, which she pushes into an opening in her partner’s belly.' Photograph: George Grall/Getty Images/National Geographic
'When the male is full with the precious cargo, he wanders off, his bright mating costume already fading. He sways and wiggles his body, settling the eggs into position where they will remain for the next few weeks, growing in a protected internal pond.' Photograph: Clive Bromhall/Getty Images/Photolibrary RM
'Most female seahorses are loyal to one male throughout his pregnancy, and do not mate again until he is ready. In fact, many seahorses are monogamous throughout whole breeding seasons, returning to the same partner time and again.' Photograph: George Grall/Getty Images/National Geographic
'Taking on the reins of pregnancy gives male seahorses one last added benefit: full reassurance that all the babies he is caring for are definitely his own – something other males, most notoriously human beings, can’t be absolutely sure of without a DNA test.' Photograph: George Grall/Getty Images/National Geographic
'The brand-new foals, each one the size of a flea, swim upward, inflating their swim bladders with a gulp of fresh air before drifting away to begin life with no more help from father or mother.'
All extracts from Poseidon’s Steed: The Story of Seahorses From Myth to Reality, by Helen Scales. Reprinted by arrangement with Gotham Books, a member of Penguin Group (USA) Inc. To order a copy for £15.99 with free UK p&p, go to guardian.co.uk/bookshop or call 0330 333 6846 Photograph: George Grall/Getty Images/National Geographic
