Gutless, buttless and surprisingly versatile

You don't find many organisms even stranger than some of those that live on coral reefs. The eye-popping mimic abilities of octopuses on a reef, for example, are only made more wonderful when you consider that they have copper instead of iron in the blood, three hearts and high intelligence. But tube worms living on hot vents in the deep sea look like a new avenue in strangeness.

These 6-foot-tall, red-tipped characters, also known as Riftia pachyptila, have no mouth, digestive tract, or anus. Instead bacteria living inside the tubeworms’ bodies in an organ called a trophosome convert carbon dioxide into organic carbon by using chemical energy. This makes them the "first known [macro] organism that makes organic carbon by different means", according to a Woods Hole press release about a paper in Science by Stefan Sievert and colleagues.

[Not to be compared with Robert Gates, late of the Iraq Study Group, now defending George W Bush's new strategy]