Pictures of sea creatures with some "stranger than science fiction" lifestyles have been released by the Wildlife Trusts, as they launch their vision for UK seas. Here a hermit crab carries a cloak anemone on its back that protects it from predators.
A report will be released today by the trusts outlining how they hope to return UK waters to a thriving marine environment within a generation. Barnacles have the longest penis in relation to body size of any animal: the organ is ten times its height.
As adults, barnacles cement themselves to rocks and are unable to move. The barnacle unfurls its long penis which roves around to find a partner, leading to jousting matches between neighbouring male barnacles.
When feeding, a starfish regurgitates its stomach through its mouth and into the shell of its prey. It can then digest its victim. If the starfish is threatened during its meal it can bite off its stomach and make a getaway, then grow a new stomach later.
Cuckoo wrasse are very colourful. Females are orange and males neon blue. All cuckoo wrasse are born female. But if they become the dominant female, they change sex, becoming neon blue to show off their new gender.
Some suggest that cuckoo wrasse may exhibit sneaky male syndrome, where female fish change into males without changing colour, enabling them to breed with females without being spotted by the dominant alpha male.
Sea squirts eat their own brains. Juveniles are tadpole-like animals and have complex nervous systems, but adults are much simpler and settle on the seabed to filter food. As they no longer need their brains and nervous systems, they digest them.
Sea hares, also known as sea slugs, are hermaphrodites and can form bizarre mating chains. These chains can even form complete circles as each slug plays female to the slug behind and male to the slug in front.
Another mating chain is created by slipper limpets, which are a type of marine snail that can create towers of 25 animals. The bottom snail is always female. When she dies the male above her will change from male to female and the chain continues.
With big eyes, fangs and a body over a metre long the wolf fish is not pretty. Feeding on sea urchins, crabs and sea snails means its teeth wear down, however the fish is able to grow a new set of teeth behind the old ones.
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