350 GLOSSARY
turnover Seespecies turnover.
vagility The ability to move actively from one
place to another.
vicariance The separation of a population or a
species into disjunct groups resulting from the for-
mation of a physical barrier.
Wallace’s line A boundary, described by Alfred
Russel Wallace, across the Indonesian archipelago,
separating faunas characteristic of the islands of the
Sunda continental shelf from those of the Sahul
shelf. Many variants of Wallace’s line have been
suggested in this region, which has been termed
Wallacea.
widow species A species that has lost its unique
pollinator (or disperser, prey, host, etc.) and is thus
heading for extinction.
zoochory Dispersal of seeds by animals,
either through their gut (endozoochous) or
attached to their skin, hair or feathers (exozoo-
chorous).
zygomorphic Having flowers with bilateral
symmetry.