A long-standing study has elucidated spermcast mating by sessile invertebrates, a widespread process involving the release of sperm into the water and its subsequent uptake by conspecific genetic individuals.
This has involved long-term culturing of colonial ascidians plus cheilostome and cyclostome bryozoans for use in laboratory experiments involving controlled matings of laboratory clonal lineages. A particular recent focus has been on polyembryony, the production of multiple clonal progeny from a single sexually produced zygote, which is universal, or nearly so, in cyclostome bryozoans.
Funding: Natural Environment Research Council, Leverhulme Trust
Image: The incubation chamber (gonozooid) of a cyclostome bryozoan