|
|
||||||||
Ecology |
2Department of Biology, Tufts University, Medford, Massachusetts 02155 USA; 3Department of Zoology, University of Florida, Gainesville, Florida 32611 USA; 4Wildlife Conservation Society, 2300 Southern Blvd., Bronx, New York 10460 USA; 5Department of Botany, University of Florida, Gainesville, Florida 32611 USA
ABSTRACT
Seed size and cotyledon morphology are two key juvenile traits that have evolved in response to changes in plant species life-history strategies and habitat associations. Correlations of these traits with each other and with other juvenile traits were examined for 70 species of trees and shrubs in Kibale National Park, Uganda. Although species with photosynthetic cotyledons were more abundant than in other tropical floras, both univariate and multivariate analyses supported trait associations expected from the literature. Trait values varied continuously across species, yet mean trait values differed significantly among habitat association types. Species with large seeds, large seedlings, thick storage cotyledons, slow germination, large-stature adults, and dispersal by large animals were common in forest and gap habitats. An opposite suite of traits was common in open habitats (grassland and edge). Analyses incorporating phylogeny (independent contrasts and omnibus tests) confirmed that these suites of traits showed correlated evolution. Cotyledon functional morphology yielded a strong phylogenetic signal, while seed mass was labile. Nevertheless, contingent change tests found that evolutionary change from photosynthetic to reserve cotyledons was more likely when disperser and perhaps seed size of ancestral species were already large, suggesting a strong interdependency among these traits.
Key Words: cotyledon morphology habitat Kibale National Park life history phylogeny seed size Uganda
This article has been cited by other articles:
![]() |
J. L. Quero, R. Villar, T. Maranon, R. Zamora, and L. Poorter Seed-mass effects in four Mediterranean Quercus species (Fagaceae) growing in contrasting light environments Am. J. Botany, November 1, 2007; 94(11): 1795 - 1803. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Baraloto and P.-M. Forget Seed size, seedling morphology, and response to deep shade and damage in neotropical rain forest trees Am. J. Botany, June 1, 2007; 94(6): 901 - 911. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |