PubMed · 2026-01-25
Island mosses and liverworts have far fewer species found nowhere else on Earth compared to flowering plants, and this study explains why: they spread too easily between continents to stay isolated long enough to evolve into new species, and when they do speciate on islands, they often spread back to the mainland and lose their 'endemic' status.
More than one-third of Macaronesian bryophyte species showed genetic signals of incipient speciation, but speciation proceeds slowly via long-distance dispersal and allopatry rather than in-place radiation.
At least 50% of Macaronesian endemic bryophytes originated from outside Europe, compared to over 90% of endemic flowering plants tracing back to European/Mediterranean ancestors — indicating very different colonization histories.
Sympatric radiation, which drives 56% of all Macaronesian flowering-plant endemics, virtually never occurs in island bryophytes, making endemism rates an unreliable proxy for speciation rates in this group.
