Innovative MTOCs organize mitotic spindles in bryophytes, the earliest extant lineages of land. Triple staining of γ-tubulin, microtubules, and nuclei here reveal that three types of MTOCs initiate spindles in bryophytes. Polar organizers in liverworts and plastid MTOCs in hornworts are unique and nuclear envelope MTOCs in mosses appear like those in seed plants. Roy C. [...]