DURHAM, N.C. -- Tropical birds are moving to higher elevations because of climate change, but they may not be moving fast enough, according to a new study by Duke University researchers.
The study, published Thursday in the peer-reviewed online journal PLoS ONE, finds that the birds aren't migrating as rapidly as scientists previously anticipated, based on recorded temperature increases.
The animals instead may be tracking changes in vegetation, which can only move slowly via seed dispersal.