Mating chain of at least four sea hares
The disdainful-looking pre-mate grasp of the masked crab !
SCUBAHUB each individual acts as a male to the one ahead of it in the ‘ queue ’ and a female to the one behind it . When they form a complete ring , everyone gets all the fun but this seems relatively rare , so ones at either end of the typical chain only get half the experience !
Crab affairs are affected to some extent by the season but also , crucially , by the female ’ s moult cycle . She is usually receptive at only one particular point in the cycle and the male crab , to make sure he is in the right place at the right time , senses a female that
will shortly become receptive and transports her about with him until she is .
For the females of many species , this means being tucked underneath the male in a ‘ pre-mating embrace ’ but there are variations on this theme . Male masked crabs use their ultra-long claws to carry their mate ( who appears decidedly disdainful ); female hermit crabs are unceremoniously dragged along by one grabbing point or another ; female edible crabs get wedged in the back of a hole , presumably because the male ’ s legs aren ’ t long enough to both walk and hold her at the same time !
In many crab species , the female ’ s receptive time is when she is soft just after shedding her old armour . This means that , after she has moulted and they have mated , the male has the important job of protecting her while she hardens up her new armour . The behaviour has evolved to protect the ‘ investment ’ of his genetic material , but it still looks rather gallant and reminds us that romance lives on , even in the world of crabs ! �
A male common hermit crab usually holds onto a female by the rim of her shell
Pair of orange clubbed sea slugs on sea mat bryozoan ; reciprocal fertilisation is underway
Courtship edible crab style ; the male is protecting the female in the back of this hole
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