The vast majority of plants are modular i.e., made up of reiterated pieces. Plant pieces also tend to be highly totipotent. You can regenerate a whole plant from just a tiny fragment of tissue. The ultimate elaboration of modularity and totipotency is clonal growth: one plant gives rise to another gives rise to another gives rise to another with no sex in between. A large proportion of plants possesses the capacity for clonal growth and, as a group, plants clone themselves in an intriguing variety of ways. Much of the recent fascination with clonal plants among botanists grew out of work by John Harper and colleagues in the 1970s (reviewed by Harper and White, 1974; Harper, 1978). During the decade that followed, other biologists joined Harper & co. in exploring the consequences of modularity for the ecology, and evolution of clonal plants, and animals (reviewed in Jackson, Buss,