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Colonial invertebrates often mix sexual and asexual methods of propagation, and a comprehensive understanding of both is required for life history study. The asexual cloning of new colonies in cupuladriid bryozoans is much better studied than the formation of new colonies by sexual reproduction. As such, the relative investments of sexual and asexual modes of propagation remain uncertain. This preliminary study explores patterns of embryonic brooding as a measure of investment into sexual reproduction. We conduct a survey of quantity and arrangement of embryos in tropical eastern Pacific cupuladriid colonies and compare this to the frequency of cloning. Species populations show considerable variation in embryonic brooding. Patterns of brooding, both across and within species strongly support the hypothesis that as cloning increases, investment into sexual reproduction decreases. We find preliminary evidence that individual cupuladriid colonies that propagate sexually may senesce like solitary organisms, while species that regularly clone only appear to experience senescence at the level of the zooid.

A model describing the positive correlation between variation in zooid size within bryozoan colonies and the amount of seasonal variation in temperature is tested in Panamanian encrusting bryozoans from contrasting seasonal regimes. Results reveal that in a natural setting the model provides accurate estimates of the level of seasonality experienced by the colonies.

A preliminary comparative analysis of colony growth and zooid size in the perennial bryozoan Flustra foliacea (Bryozoa: Cheilostomatida) reveals reduced colony growth in the Bay of Fundy relative to growth in the Menai Straits and the Skagerrak, while seasonal fluctuations in zooid size are in synchrony with temperature regimes. Such retrospective morphometric analyses may allow inferences of primary productivity and thermal regimes and provide insights into the life histories of both Recent and fossil bryozoans.