The ranges of the two species do not overlap, and they occur allopatrically
Given that most species probably originated allopatrically
and that faunal differentiation in Amazonia took place during the entire Cenozoic (Tertiary--Quaternary, i.e.
phalerata in Madre de Dios, Peru, without evidence of hybridization, and allopatrically
all along the Huallaga valley.
cymosum, arisen allopatrically
, suggesting that the tetraploids had multiple origin.
The bulk of Turneraceae are found east of the Andes, suggesting that Malesherbiaceae evolved allopatrically
malma often exists allopatrically
in high elevation reaches of streams dominated downstream by S.
In these cases, the species that have originated may have evolved sympatrically (within the same area) or allopatrically
(in different areas), though allopatric evolution is more common.
Results of the present analyses (Table 3) suggest that black guillemots diverged from the Pacific species of guillemots allopatrically
, probably through isolation of Arctic and Pacific [TABULAR DATA FOR TABLE 3 OMITTED] populations by the Bering Landbridge through the early Pleistocene.