Article: Brachiopod food and feeding processes
By considering the available relevant data on morphology, physiology, histology, and biochemistry of the lophophore and digestive tract of brachiopods, and by filling in gaps in the knowledge with analogies drawn from filter-feeding bivalves, a relatively detailed account of feeding processes in brachiopods is presented. It is shown that, except in the expulsion of wastes, similar feeding processes appear to occur in both the inarticulates and articulates. The articulate method of expelling faeces through the mouth has little disadvantage over the inarticulate method of expulsion through the anus. Direct evidence shows that brachiopods are able to assimilate dissolved substances; indirect evidence suggests that bacteria and colloids are utilized, that organic detritus and some algae are important food sources, and that animal forms of life are not important foods for brachiopods. There is no reason to suggest that the food categories of fossil brachiopods differed from those of extant forms. Suggestions are made on how to obtain more information on the food and feeding processes in brachiopods.