Worms
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The concept of a worm being interesting is probably pushing it, a tube with a mouth at one end, anus at the other and a gut in between isn’t stimulating dinner party talk. One of the problems is we have seen worms since we were born, wiggling everywhere. The marine worms though are a different class of organisms they have style.
Bude, of course, is nationally recognised as the home of the honeycomb, the beaches at low tide reveal extensive sculptures that outclass human monuments. These reefs are impossible not to see but many of the worms are far more secretive. The title of worm covers several groups, ribbon, proboscis, bristle, acorn, rag, flat and bootlace are just a few, each has several species cleverly adapted to a specific environment. Living in the sand is hard, it is mobile so you can become exposed, it is abrasive, it collapses as you dig and it changes once wet, it becomes fluid. Several worms overcome this by building tubes. The mason worm glues sand together and produces a nifty frill at the end that protrudes above the sand. Sand is a great construction material but worms can also create very hard calcareous tubes, the keel worms and spirorbis species do this to allow them to live on stones and rocks in full view. Here they simply withdrawal into the tube and are safe. A static life requires a feeding strategy and this normally means filter feeding. Keel worms underwater transform with delicate feather-like appendages waving in the water grabbing passing plankton. Wet sand and rocks are good hunting areas if you are quick, so other groups are powerful and very able to move. These are often thin so allowing them to get into tiny crevices and hunt prey. They have well-developed mouthparts that grab and hold, prey here is slippery and it pays to keep hold of a meal when a wave passes by. Ragworms swim through mud and wet sand, they are often flattened to assist this. They also swim in water by a strange looping motion. Flatworms glide over rocks so thin you can see through their bodies. These creatures lack an anus, defy identification and have amazing powers of rejuvenation from separated body parts. One area of the shore is so fertile that the worms have overcome the seemingly impossible problem of a lack of oxygen to exploit it. Mud is anaerobic just below the surface, the small particle sizes prevent free infusion of air. Maintaining a tube to the air is difficult there is little to build it with. So they have evolved long red tentacles and high haemoglobin levels to cope with the deficiency. If you lift a rock at low tide that is in anaerobic mud you might see these disappearing like some alien species. The sheer number of worms in mudflats is astronomical and they are considered one of the most productive environments on the planet. Where the mud is firmer lugworms build U shape burrows, one end is the rubbish dump the other for feeding. Perhaps worms aren’t so boring after all, but trying to put a name to one, now that is a huge challenge. |