XVI International Botanical Congess
We investigated the biology of seaweed populations from southern Baja California. Pterocladiella capillacea (Rhodophyta, Gelidiales) is frequent in rocky areas of the Pacific coast. Its frond demography paralleled the dynamics of stand biomass, being highest in summer and lowest in winter. Tetrasporic fronds occurred year-round, cystocarpic and fertile male fronds, in winter. A comparison with other clonal red algae suggests separate evolutionary pathways for vegetative and for reproductive dynamics. We also studied Caulerpa sertularioides (Chlorophyta, Halimedales) from sandy subtidal areas of the Gulf of California. Stands suffered great biomass losses in summer, possibly due to tropical storms, but recovered rapidly through clonal growth. We assessed the genetic diversity of this Caulerpa population with allozyme markers, one of the first such studies in Mexico.