| Bryozoans
In recent years we have developed a particular interest in bryozoan ecology and with Micha Bayer (now at Royal Botanic Garden, Edinburgh undertaking research on diatoms) I undertook laboratory cloning and propagation of bryozoans (and other sessile invertebrates) on glass slides (refs. A,E,K,N,S). This permits replication of genotypes for the experimental analysis of, for example, Genotype by Environment interaction in response to biotic and physical variables. Our work has primarily concerned Electra pilosa and our early projects focused on polypide regression and regeneration, at both the zooid and colony level, in response to differing food regimes and temperatures (A). Latterly we concentrated on investigating the causal agents underlying an unusual inducible morphology - the formation of grossly extended median proximal spines - in Electra pilosa (N). Studies on another species of bryozoan have implicated nudibranch predation as the inductive agent in a similar defensive response: our work showed specialist nudibranch predators to be unimportant to Electra in this respect, as are genotypic responses to overgrowth competition (allogenic and autogenic) with other Electra colonies and with other taxa (bryozoans and ascidians). The formation of extended spines in Electra pilosa is, in fact, a phenotypic plasticity which is apparently unique in being induced by an abiotic factor. We showed the crucial environmental cue to be wave-related abrasion, by utilizing an experimental tank system to mimic this in the laboratory (N). Collaborations continue with Steve Hapeman who is utilising our closed experimental colonies for morphometric analysis and comparison with fossil species.
(For more about inducible morphology in Electra click here.)
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