Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Fossil and genetic history of a pinyon pine (Pinus edulis) isolate.

Abstract

The most isolated northern stand of Colorado pinyon pine (Pinus edulis) at Owl Canyon, Colorado, was studied. The stand had a broad and flat size class distribution, indicating an expanding population, with the oldest and largest trees near the centre of the grove. Analyses of fossil packrat (Neotoma sp.) middens within the grove showed that the stand originated through long-distance dispersal, probably by birds. Pollen and macrofossil records suggested that colonization started between 1290 and 420 yr ago (the latter being the age of the oldest tree in the grove). Electrophoretic data showed that the stand does not appear to have suffered significant losses in genetic variation. The genetic complexity of 'founder effects' is discussed.