Biological Sciences

Plant Evolutionary Biology and Ecology

Prof Scott Armbruster , Dr R. Barrales

The research on our lab is based on the ecology and evolution of plants, plant-animal interactions, and biogeography of organisms. We use molecular markers (chloroplastic and nuclear DNA, ISSR, AFLP, microtsatelites) to build the phylogenetic relationships of the organism. We are particularly interested in understanding:

1. How natural selection operates in the wild by using plant-animal interactions (both pollination and herbivory), the geographic (mosaic) distribution of the interactions, and their consequeces in local adaptation, ecotipic differentiation and local isolation in plants
2. The role of pollinators on shaping flower morphology, the patterns of selection of traits and correlations among traits, and the effects on the female and male fitness of the plant as a result of the pollination interaction
3. Quantitative genetics and development of floral traits involved in attracting, rewarding, and manipulating pollinators; correlated evolution, constraint, and evolvability of floral traits.

The role of pollinators on shaping the flower morphology in Dalechampia scandens (1. Hypanthidium bee and 2. Euglossa bee, both collecting the resin) and the importance on herbivores on the predation of leaves, blossoms and seeds (3. Hamadryas butterfly checking if it is a Dalechampia plant, 4. caterpillar feeding on leaves)

4. Plant breeding systems, reproductive assuarance, inbreeding and outbreeding depression and evolution of selfing in plants
5. Evolution and distribution of sex polymorphisms in plants, with emphasis in heterostyly and the Darwinian hypothesis of Lloyd and Webb (1992 a,b) of evolution of heterostyly

Evolution and distribution of sex polymorphisms in plants, with emphasis in heterostyly and the Darwinian hypothesis of Lloyd and Webb (1992 a,b) of evolution of heterostyly, being the genus Narcissus and Linum systems supporting this hypothesis (5. traditional –linear- heterostyly in L. bienne, 6. three-dimensional heterostyly in L. suffruticosum; 7. flower morphology in L. suffruticosum, with a wide flower tube; 8. flower morphology of the linear heterostylous L. narbonense, with a narrow flower tube).

6. Conservation biology in particular in threatened ecosystems, like the tropics or the Mediterranean
7. Molecular markers (chloroplastic and nuclear DNA, ISSR, AFLP, microtsatelites) to build the phylogenetic relationships at the species and population level and inffer the patterns of divergence and convergence of the plant-animal interactions, evolution of traits and character reconstruction, genetic diversity of populations, inbreeding and outbreeding depression and paternity.

Below are examples of phylogenetic trees produced for different systems

Phylogenetic reconstruction of the evolution of the pollination system in Dalechampia (9, Armbruster and Baldwin, Nature 1998) and the evolution of heterostyly in the genus Narcissus (10, Perez et al. NewPhy 2004 and Pérez-Barrales et al. NewPhy 2006) and Linum (11, Armbruster et al. NewPhy 2006), supporting the darwinian hypothesys of Lloyd and Webb (1992 a, b)

Our fieldwork areas include: Alaska, California, Yukon Territory, Russian Far East, Norway, Svalbard, Scotland, Western Australia, Mexico, Guatemala, Honduras, Costa Rica, Panama, Trinidad, Ecuador, Peru, Brazil, Venezuela, French Guiana, Suriname, Bolivia, Madagascar, South Africa, Gabon, Tanzania, Thailand, Spain and Morocco.