Biological Oceanography

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baker’s guild, and so on. These had limited entry by an apprenticeship system; held
the secrets of the craft as closely as practice allowed; and struggled artfully to keep
prices high by control of supply. There were often social aspects as well, with a guild
hall for meetings, weddings, and temporary shelter. Some had simple insurance
schemes for members. For ecologists, the term is akin to the Eltonian niche, the
notion that each species has a role in the ecological community. Members of guilds
are known (or often just believed) to have similar functional modes in their habitats.
Of course, each modern user of the term has his or her own intentions for it, so some
caution is in order when adopting guild schemes from their developers.


Table 14.1 Summary of a functional classification of polychaetous annelids by
Fauchald and Jumars (1979). Acronym designations are followed by families with
members included and one or more example genera. H, herbivore; C, carnivore; B,
burrower; F, filter feeder; S, surface deposit feeder; J, jawed; T, tentaculate; P,
pumping; X, other feeding morphology.


(^) Macrophages
HMX – Non-jawed, motile herbivores that eat large particles are all from families of small-bodied polychaetes.
So the particles they eat are only relatively large. The only well-studied family is the Paraonidae – Paraonis
fulgens. They burrow about in the surface of sediments and take single diatoms and foraminiferans as food.
HMJ – Typical are the Nereidae – Nereis. These usually form mucous tubes in the sediment, but can move from
them and form new tubes. They emerge from their tubes and explore the neighboring zone of the surface
sediment. Most eat bits of drifting plant (Fig. 14.12a).
HDJ – Onuphidae – Diopatria cuprea. Build a fibrous tube of mucus and protein, the tip of which sticks up
above the sediment surface. The worm decorates it with stones, bits of wood, sediment, or growing algae. Move
rarely, but they can, and adults can establish new tubes. Large bits of alga passing the tube are held and chewed
(Fig. 14.12b).
CMJ – Other Onuphidae, Nereidae, and Syllidae. Crawl along, sometimes on hard substrates, chewing on
sponges, cnidarians, etc. (Fig. 14.12c).
CMX – Amphinomidae – Hermodice carunculata. These chew on coral polyps, etc. They may live in coral sand,
especially during mid-day. They have toxic spines. There is an eversible, muscular lower lip for rasping and
squeezing prey (Fig. 14.12d).
CDJ – Glyceridae – Glycera spp. and others. These have enormous, eversible probocides armed with a circlet of
spines, which connect in some species to a poison gland. They are ambush predators, sitting quietly in the sand
and popping the proboscis out to catch passing prey (Fig. 14.12e). This family is pretty flexible, however, and
includes detritivores.
Microphages
Filter-feeders
FDT – Tentaculate, discretely mobile – Sabellidae (e.g. Sabella sp.). These are tube-dwelling and only move if
displaced. The crown of tentacles makes a current by moving as a whole. Ciliary currents along tentacle
filaments move particles to the mouth (Fig. 14.12f).
FDP – Pumping – Arenicolidae – Arenicola spp. Worms that live in U-tubes. They move water through the tube
by peristaltic pumping with the body. This pulls water through a sand plug ahead of the animal, which is eaten
after a period of filtering. Fauchald and Jumars indicate that despite prolonged study the feeding is still not fully
understood (Fig. 14.12g).
FST – Sabellaridae. Tubiculous, reef-building polychaetes. Feeding similar to the Sabellidae.
FSP – Chaetopteridae – Chaetopterus spp. These live in a U-tube, pumping with swinging movements of large

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