Paradoxical polyembryony? Embryonic cloning in an ancient order of marine bryozoans.

Prolific polyembryony is reported in few major taxa, but its occurrence has generated theoretical debate on potential conflict between sexual and asexual reproduction. It is, therefore, important to genetically confirm a widely cited inference, based on microscopy, that polyembryony characterizes marine bryozoans of the order Cyclostomata. Microsatellite genotyping of brooded embryos and maternal colonies conclusively demonstrated polyembryony, while genetic variation among broods within colonies indicated outcrossing via water-borne sperm, in the rocky-shore species Crisia denticulata.

Kin or self-recognition? Colonial fusibility of the bryozoan Celleporella hyalina.

We estimated fusion frequency with respect to coancestry in the bryozoan Celleporella hyalina, whose briefly planktonic sexually produced larvae settle on algal substrata and proceed to form encrusting colonies by iterative budding. Frequency of fusion between paired colonies growing on an artificial substratum was positively correlated with coefficient of relatedness, with allorecognition ability increasing during the early stages of colonial growth after larval settlement. Parents repressed the growth of F1 progeny with which they had fused.