Abstract Detail

Polymorphism - from morphology to interactions

Glennon, Kelsey [1], Mathura, Sadhna [2], Payne, Stephanie [3].

Examining underlying pigments and evolutionary patterns of flower colour polymorphisms in Hypoxidaceae.

Flowers are a charismatic feature of angiosperms, unquestionably due to the variety in colour and shape. This polymorphic trait exists at varying scales, within populations and across taxonomic groups, and is the foundation for evolution and diversification. A macroevolutionary approach to investigate flower colour patterns informs our understanding of how or when these transitions may occur, and their evolutionary implications. We examined the colour pigments and patterns of evolution represented in the cosmopolitan, monocot family Hypoxidaceae (Star Grass). We collected pigment data using petal peels for 59 taxa and GC-MS data for representative flower colours. We mapped flower colour (e.g., yellow, yellow/orange, pink/red, and unpigmented flowers) on a recently published phylogeny to examine patterns of flower colour polymorphisms. Data showed that colours are the result of carotenoids, anthocyanins, and chlorophyll, as well as structural colour in one Cape genus. GC-MS data indicate that malvidin may be responsible for the pink-red colours. Our results suggest that there were two primary transitions from yellow flowered species to anthocyanin pigments and each genus comprises a nonpigmented species and at least two genera comprise colour-polymorphic species. Additionally, data show that one species changes the frequency of colour morphs over a flowering season. In one genus, we find evidence for anthocyanin pigments potentially coinciding with carotenoid pigments to produce orange individuals. This work provides a foundation to explore flower colour polymorphisms at a microevolutionary scale.

1 - University Of The Witwatersrand, Animal, Plant & Environmental Sciences, Private Bag X3, Johannesburg, GT, WITS 2050, South Africa
2 - University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, 2000, South Africa
3 - School of Animal, Plant, and Environmental Sciences, 1 Jan Smuts Ave, Braamfontein, 2000, South Africa

Keywords:
flower color polymorphisms
Monocots
Star Grass
South Africa.

Presentation Type: Colloquium Presentations
Number: C2003
Abstract ID:1026
Candidate for Awards:None