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Barnacles Reach Out To Valentines

Barnacles are stuck to rocks, which presents a challenge for mating. But evolution has endowed them with unique abilities. Cynthia Graber reports.

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It’s Valentine’s Day.  Even for barnacles.  Which are stuck to rocks.  But evolution has endowed these stationary creatures with some curious abilities, according to research was published on-line in the Proceedings of the Royal Society. Male barnacles have members that can stretch to eight times their body length to reach a similarly stuck female. They have other problems, though—strong waves and tides.

Scientists at Canada’s University of Alberta discovered that barnacles cope with this challenge by developing differently shaped genitalia. Barnacles that cling to rocks on wave-exposed shores have shorter, wider organs, so they can maintain control in violent waters. Those that live in coves protected from crashing waves have longer, slimmer ones. Researchers transplanted young barnacles living in protected coves to unprotected ones, and vice versa. And the animals developed accordingly. For example, barnacles from calm areas that were moved to turbulent seas grew short, wide members. This experiment shows that barnacles can develop their digit to suit local conditions, and reach through churching waters to connect with someone special.

—Cynthia Graber

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Barnacles Reach Out To Valentines