| Sessile colonial invertebrates often fuse with conspecifics to form chimeras. Chimerism represents an unequivocal instance of withinindividual selection where genetically different celllineages compete for representation in the somatic and gametic pools. We analyzed temporal and spatial variations in somatic celllineage composition of laboratoryestablished chimeras of the hydroid Hydractinia symbiolongicarpus (Cnidaria: Hydrozoa). Using three clones with different allotypic specificities (i.e., two rejecting one another but fusing with a third one), we established two classes of twoway chimeras, a single threeway chimera class, and an incompatible interaction as control. Chimeras were sampled at five time intervals for a year. Celllineages in samples were... |
