Brachiopods

In contrast with fast, strong predators, organisms with a limited range of movement, or limited control over their movements—those that cannot run away from potential predators—are well represented among the chemically defended (Table 1). Sessile marine invertebrates are particularly accomplished chemists these include in their ranks sponges, antho-zoan corals, crinoid echinoderms, polychaetes, bryozoans, brachiopods,... 

Collins, M.J., G. Muyzer, G.B. Curry, P. Sandberg, and P. Westbroek. 1991. Macromolecules in brachiopod shells Characterization and diagenesis. Lethaia 24 387-397. 

Endo, K., D. Walton, R.A. Reyment, and G.B. Curry. 1995. Fossil intra-crystalline biomolecules of brachiopod shells Diagenesis and preserved geo-biological information. Organic Geochemistry 13 661-673. 

Fig. 3.25 data of bulk rock calcite and brachiopods overtime for (a) measured and (b) shifted values (upward shift of 2%o for all bulk rock data) (Jaffr6s et al. 2007)... 

Of special geological interest is the isotopic analyses of coeval carbonate-phosphate pairs (Wenzel et al. 2000), which helps to distinguish primary marine signals from secondary alteration effects and sheds light on the causes for 5 0 variations of fossil ocean water. Wenzel et al. (2000) compared Silurian cal-citic brachiopods with phosphatic brachiopods and conodonts from identical stratigraphic horizons. They showed that primary marine oxygen isotope compositions are better preserved in conodonts than in brachiopod shell apatite and suggested that conodonts record paleotemperature and ratios of Silurian sea water. 

Leclerc AJ, Labeyrie LC (1987) Temperature dependence of oxygen isotopic fractionation between diatom silica and water. Earth Planet Sci Lett 84 69-74 Ldcuyer C, Grandjean P, Reynard B, Albarede F, Telouk P (2002) B/ °B analysis of geological materials by ICP-MS Plasma 54 application to bron fractionation between brachiopod calcite and seawater. Chem Geol 186 45-55... 

Sampling in Mediterranean deep waters has revealed the first secondary n tabolites from brachiopods and unique 10-hydroxyeicosa- and docosapolyenoic acids from scleractinian corals. That these fetty acids have also been foimd in a deep-water pre-Antarctic antipatharian coral (Table 9.III) must be attributed to convergence. Deep-water Mediterranean medusae and a lithistid sponge from New Caledonia, Corallistes sp., contain huge amounts of free porphyrins. 

D Ambrosio, M. Guerriero, A. Pietra, F. (1996C) Glycerol enol ethers of the brachiopod Gryphus vitreus from the Tuscan archipelago. Experientia, 52, 624-7. 

The third type of compound used extensively as a structural component is apatite, CadPO jX. Hydroxyapatite (X = OH) is the major component of bone tissue in tbe vertebrate skeleton. It is also the principal strengthening naierial in teeth. Partial formation of fluorapatite (X = F) from application of fluondes strengthens the structure and causes it to be less soluble in the add formed from fermenting organic material, hence a reduction of caries. Fluorapatite is also used structurally in certain Brachiopod shells. 

These geochemical tracers have been successfully applied to studies of the shells of a variety of marine organisms including bivalve and gastropod mollusks, ostracods, forams, brachiopods and solitary corals (47, 54, 57, 58). In the case of mollusk shells, for example, serial microsampling around the spiral whorls from earliest to oldest growth revealed sinusoidal variations in isotope ratios, which result from shell deposition in a seasonal environment (47, 50, 62-64). Our previous work showed this to be true of Olivella shells as well, where 8,sO levels fluctuate from warm summer temperatures to cold spring and winter temperatures (38). 

A number of invertebrates deposit phosphate in their shell structures24. In the articulate brachiopod shell — Lingula — apatite crystallites occur up to about 1000 A long. Little is known, however, on the nature of shell organic matter, except that the amount of chitinous material exceeds that of protein fraction by a factor of two408. ... 

Jope, M. Constituents of brachiopod shells. In Comprehensive biochemistry (eds. M. Flor-kin and E. H. Stotz). Vol. 26C. Amsterdam Elsevier Publ. Comp. 1971, 749—784. 

McConnell, D. Inorganic constituents in the shell of the living brachiopod Lingula. Geol. Soc. Amer. Bull. 74, 363- 364 (1963). 

Chalk is made of the shells of marine algae (that is, plants). It is a form of limestone. Most other limestones are formed from the debris of animal structures, for example brachiopods and crinoids. 

FIGURE 3.9 Selected metabolites from bryozoans and a brachiopod. 3.9.1 Securine A from Securiflustra securirons.209 3.9.2 Bryostatin 18 from Bugula neritina,210 3.9.3 Glycerol ethers from the brachiopod... 

Thayer, C. W., Brachiopods versus mussels competition, predation, and palatability, Science, 228, 1527, 1985. 

McClintock, J. B., Slattery, M., and Thayer, C. W., Energy content and chemical defense of the articulate brachiopod Liothyrella uva from the Antarctic Peninsula, J. Exp. Mar. Biol. Ecol., 169,... 

Pennington, J. T., Tamburri, M. N., and Barry, J. P., Development, temperature tolerance, and settlement preference of embryos and larvae of the articulate brachiopod Laqueus califomianus, Biol. Bull., 196, 245, 1999. 

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