A few groups have evolved to live in terrestrial environments, but are restricted to humid areas. Some have even evolved tubes that open inwards from the skin which work like simple lungs, absorbing oxygen from the air and allowing release of waste gases.
Most bristle worms are scavengers, but some are good predators, eating fishes and coral. Others like to eat algae. They are usually found hiding in reefs and rocky places. They crawl along the sea floor or the bottom of a tide pool, looking for something to eat.
Lugworm
The lugworm ("Arenicola marina"), also known as the sandworm, is a large marine worm of the phylum Annelida. Lugworms make the coiled tubes of sand that are a familiar sight on a beach at low tide. The lugworm itself is not seen except by people who dig them up from curiosity or to use as fishing bait.
The lugworm lives in a U-shaped tube in the sand, and filters out its food from the water.
Arenicola marina can grow to about 5 inches long (13 cm). Its body is segmented, like that of an earthworm. It has bristles in the middle of its body. It is a polychaete. It also has well-developed blood-vessels, and gills to breathe in the water.
Although the textbook example is usually "Arenicola marina", there is a second species, "Arenicola defodiens", which lives a similar life. It grows to about 9 inches long (23 cm)
Alitta succinea
Alitta succinea, also known as the pile worm or clam worm, is a common polychaete worm.
It is a species of ragworm or sandworm. The terms can refer to any one of a number of other species.
This worm can reach up to 15 centimeters (6 inches) in length. Most specimens are smaller than this. It is brown coloured at the rear, and reddish-brown on the rest of its body. It has a head with four eyes, two sensory feelers or palps, and eight tentacles. It is a freeswimming polychaete, scavenging on the bottom of shallow marine waters.
Clam worms are an important food source for bottom-feeding fish and crustaceans. They can protect themselves by secreting a mucous substance which hardens to form a sheath around them.
Planktonic larvae develop, grow into adults and eventually sink to the bottom of the water.
Protozoa
Protozoa are small (but not simple) organisms. They are single-celled heterotrophic eukaryotes, which eat bacteria and other food sources.
It is an old term, and the wider term protist is generally preferred today. However, 'protozoa' is often used for convenience, especially in junior education. It is a convenient hold-all term, and most systems of taxonomy classify 'protozoa' into several different phyla.
The term is problematic because modern biochemical and genetic techniques show that it includes several quite different kinds of cells. They are found only in moist or aquatic habitats. Many protozoan species are symbionts, some are parasites, and some are predators of soil bacteria and algae. About 30,000 protozoan species are known.
Sandworm
The name Sandworm' can refer to different species:
It can also stand for huge worms in the book Dune by Frank Herbert, see Sandworm (Dune)
Hematophagy
Hematophagy is the habit of certain animals to feed on blood. Blood is rich in proteins. Examples of animals that feed on blood are mosquitoes, vampire bats and leeches.
Crinoidea
The Crinoids are a class of Echinoderms. They have two forms, the sea lilies, stalked forms attached to the sea floor, and the feather stars, which are free-living.
All crinoids are marine, and live both in shallow water and in depths as great as 6000 meters. The basic echinoderm pattern of fivefold symmetry can be recognized, but most crinoids have many more than five arms. Crinoids have a mouth on the top surface that is surrounded by feeding arms.
The crinoids have a long history. They were the first echinoderms to appear in the fossil record, and have kept their early structure throughout their long career. They were extremely common in the Palaeozoic, and some rocks from the Carboniferous consist almost entirely of fossil crinoids.
Crinoids' mouths faces up towards the surface of the ocean, and the stalked forms feed on the detritus which comes down to the bottom. The mouth is surrounded by many feathery tentacles. They have a U-shaped gut, and their anus is located next to the mouth.
The crinoids were almost wiped out by the extinction event at the end of the Palaeozoic era. Four whole classes became extinct, and the few that survived became the only living class, the Articulata. The stalked members of the class sufered from heavy predation in the Mesozoic. and now all the remaining sea lilies are in deep water, where the competition is less fierce. The feather stars have been much more successful.
In 2005, a stalked crinoid was recorded pulling itself along the sea floor off the Grand Bahama Island. The recording showed a crinoid moving at much faster speeds than was thought possible.
The free-living feather stars first appear in the Upper Triassic. They are related to starfish. As juveniles, they are attached to the sea bottom by a stalk, as their ancestors were. In the adult stage they break away from the stalk and can move about. Some can swim by undulating movements of the arms. Usually, feather stars creep about by using projections at the bottom of the crown, called cirri. They are the only crinoids in shallow water, and are all in the Order Comatulidae. Their flexible arms and ability to choose their feeding grounds was undoubtedly important in their success and survival.
During the day, they roll into a ball. But at night, they spread out their arms to catch plankton.
Feather stars arrange themselves so the fan faces the flow of the current. The posture serves to present the maximum area of food-collecting surfaces to the incoming water flow, so that more particles will settle on them. They are found mostly in shallow water.
Yorkshire Dales
The Yorkshire Dales (also known as the "Dales") is the name given to an upland area, mostly in Yorkshire, in Northern England. Most of the area falls within the Yorkshire Dales District National Park, created in 1954. The "Dales" is one of the twelve National parks of England and Wales. The area is so called because it is a collection of river valleys ("dale" comes from a Danish word for valley), and the hills in between them. The area is mainly in the historic county of Yorkshire, but today is partly in three modern counties : North Yorkshire, West Yorkshire, and Cumbria.
Suwanee, Georgia
Suwanee is a city in the American state of Georgia. It is in Gwinnett County. In 2005, about 12,500 people lived in Suwanee. According to the United States Census Bureau, the city has a total area of 25.6 km² (9.9 mi²). 25.4 km² (9.8 mi²) of it is land and 0.2 km² (0.1 mi²) of it (0.71%) is water.
Cumming, Georgia
Cumming is a city in the American state of Georgia. The city is the county seat of Forsyth County. About 5,800 people live in Cumming. According to the United States Census Bureau, the city has a total area of 15.3 km² (5.9 mi²). 15.3 km² (5.9 mi²) of it is land and 0.1 km² (0.04 mi²) of it (0.34%) is water.
Athens, Georgia
Athens is a city in the American state of Georgia.
It is the county seat of Clarke County.
The University of Georgia is in Athens.
Anaerobic digestion
Anaerobic digestion is the way microorganisms break down organic matter without oxygen. This process can happen naturally, but it is called anaerobic digestion only if it is supported and contained. An anaerobic digester is an industrial system that supports these natural process to treat waste, produce biogas that can be used to power electricity generators, provide heat and produce soil improving material.
Clarke County, Georgia
Clarke County is a county in the American state of Georgia. The county seat of Clarke County is Athens, Georgia. Clarke county was formed on December 5, 1801 and named after Revolutionary War hero Elijah Clarke. The University of Georgia is in Clarke County. Clarke county has 104,439 people.