Phenotypic integration and functional modularity in keel flowers

CÓRDOBA, SILVINA ALEJANDRA; COCUCCI, ANDREA

Botucatu, Sao Paulo.

Simposio; International symposium and workshop Legume Morphology: Current Knowledge and Future Directions; 2015

UNIVERSIDADE ESTADUAL PAULISTA JÚLIO DE MESQUITA FILHO - UNESP CÂMPUS DE BOTUCATU INSTITUTO DE BIOCIÊNCIAS STAEPE

Phenotypic integration and modularity provide insight into the evolution of flower morphology. When applied to flowers, the former refers to the covariation of traits as a unit; however, given developmental or functional division within flowers covariation could occur among a group of trait, forming intrafloral modules. In flowers with complex pollination mechanisms pollen transfer requires high functional integration of traits; however it has been suggested that the low level of integration found in Angiosperms could be the result of intrafloral modularity. We evaluated the pattern and magnitude of floral integration in seven species of keel flowers. We detected functional modularity testing the association of morphometric variables with the force needed to open the keel as biomechanical variable. Then we compared hypothetical functional and developmental matrices with empiric matrices to test whether the functional or developmental structure better explained the covariation patterns. Except for one, species showed morphometric traits from keel and/or wings associated with force while no trait from flag was associated with the biomechanical variable. The patterns of integration differ among all species and functional modularity was founded in two of them. Integration indices were low but consistent with other Angiosperms suggesting that intrafloral modularity may be widespread.