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| | Most of the time, male and female lobsters are hostile to each other. If they detect each other’s scents in the water with their antennules, they will attack. However, when female lobsters shed their shells they release a sex [[pheromone]] that male lobsters find strangely arousing. In fact, as smell and taste underwater are both ways of detecting chemical molecules, the male lobster could be said to taste the female as much as smell her during this time. | | Most of the time, male and female lobsters are hostile to each other. If they detect each other’s scents in the water with their antennules, they will attack. However, when female lobsters shed their shells they release a sex [[pheromone]] that male lobsters find strangely arousing. In fact, as smell and taste underwater are both ways of detecting chemical molecules, the male lobster could be said to taste the female as much as smell her during this time. |
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| − | In the Middle Ages, natural scientists were very puzzled by the fact that the male lobster has no [[penis]]. Later scientists took a long time (and many strange theories involving things like collapsible penises) to discover how lobsters fertilized their eggs. Things were complicated by the discovery that the female lobster has no [[vagina]].
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| − | In 1895 a 250-page treatise called The American Lobster, its Habits and Development, by Francis Herrick, explained that a female lobster has a tiny pouch at the base of her tail, where she can store a male lobster’s sperm until she is ready to extrude her eggs. In the same position on his tail, the male lobster has a pair of hardened swimmerets with grooves along the inside edge. Herrick dissected lobster [[testes]] and discovered that male lobsters package their [[sperm]] into gelatinous capsules called [[spermatophore]]s. Using their swimmerets to prop open the female’s receptacle, they [[ejaculate]] these packets down the grooves and into the pouch. The last spermatophore hardens into a plug to block the opening, to prevent another male’s sperm packages from entering.
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| − | However, despite the lack of a traditional penis-and-vagina, lobster sex involves the missionary position. After the moulting female’s new shell has hardened just enough for the male lobster to handle her, he mounts her from behind and uses his walking legs to rotate her body to face him. They fan each other with their swimmerets, and then after about fifteen minutes of this foreplay the male ejaculates his spermatophores into her [[seminal receptacle]]. This part of the act of mating takes about eight seconds.
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| − | The pheromones released by the moulting female lobster can even give the male lobster the patience to withstand rejection. If he keeps his courtship up for long enough, he can often persuade the female to let him mount her. The reverse happens too. When the male is not interested, the female sometimes sidles up and tries to slip under him. This does not usually succeed, but the pheromone is strong enough to restrain him from violence.
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| − | Pouring water from a tank in which a female lobster has moulted is enough to encourage hard-shelled male and female lobsters to have [[sex]] rather than fight each other. However, if two male lobsters are put in the tank they become more antagonistic than ever. No [[homosexual]] lobsters have been observed.
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| − | The dominant males wait in their shelters, urinating out of the doorway at any females who come calling. The female approaches the male before she is ready to moult, and urinates back at him, her sex pheromones persuading him to cease his aggression. He stands on tiptoe, fanning her urine around his home with his swimmerets. The most dominant males are the most likely to be chosen – an evolutionary tactic that not only secures good genes for the offspring, but also secures good protection for the female during her time of vulnerability after shedding her shell. However, sadly for feminist lobsters, the way a male shows his dominance is to beat up and bully not only the other males but also the females.
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| − | The tactic of mating only when the female has moulted also confers evolutionary advantages on the male. The female’s previous hard shell acted like a chastity belt and would not have admitted any other male’s sperm, so he is assured that his sperm will fertilize her eggs. The male acts protectively towards the female until her shell hardens – about two weeks – and then they resume their previous antagonistic relationship.
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| − | In controlled environments, females time their moults sequentially, so that as one male-female pair splits up, another female is ready to move into the male’s hiding place and mate with him. It appears that the female’s PMS (pre-moult-syndrome) is timed by olfactory signals from the male-female pairs.<ref> The Secret Life of Lobsters, by Trevor Corson, pub. Harper Perennial 2005, ISBN 0060555580</ref>
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| | ==Lobster egg hatching== | | ==Lobster egg hatching== |