ibclogo XVI International Botanical Congess


Abstract Number: 2146
Session = 3.7.7


EVOLUTION AND ECOLOGY OF BIRD-DISPERSED PINES WITH REFERENCE TO RECENT SYSTEMATIC DEVELOPMENTS


D.F. Tomback and L.P. Bruederle. Biology, University of Colorado at Denver


Cone and seed morphology are traditionally used for pine taxonomy, particularly within Pinus subgenus Strobus. In the last two decades we have learned that large, wingless seeds and seed retention by cones correspond to dispersal by scatterhoarding birds-a derived condition associated with stressful environments. Pines in subsection Cembra are coevolved with nutcrackers (Nucifraga), Subsection Cembroides may be coevolved with New World jays (e.g., Gymnorhinus). Subsection Strobi reveals a mix of morphologies with a geographic transition from wind- to bird-mediated seed dispersal. Recent molecular data suggest that coevolution with seed dispersers may result in convergent morphology. Subsection Cembrae, for example, appears polyphyletic. Pine seed-dispersing corvids are also polyphyletic with convergence in morphology and cognitive abilities.


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