Fascinated by life cycles and micromorphology of freshwater algae

Abstract

Organisms exhibit life cycles in which they change their morphological features extensively by means of reproduction. The life cycle is a fundamental and impressive attribute of organisms. Freshwater green algae are very suitable for the life cycle research because methods for cultivation and induction of sexual reproduction have been published in these algae. Here, our previous morphological studies of freshwater algae carried out in these 40 years are reviewed, especially in the life cycle and micromorphology. Results of my light microscopic observations of the colonial volvocalean life cycles in the last century triggered and based our subsequent studies of the phylogeny, sex-specific genes and multicellularity, using the molecular genetic, genome and microscopic data of the colonial Volvocales. In addition, our electron microscopic observations of freshwater green alga Carteria and glaucophytes Cyanophora and Glaucocystis demonstrated their more natural three-dimensional ultrastructural features that contributed much to the species taxonomy of these genera. Since missing link species of the colonial Volvocales recently found from the natural habitats exhibited very interesting morphological features of the life cycle, further field works are very fruitful for future studies of morphology and diversity of the freshwater algae.