Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Entire DC Network
Reproductive Ecology And Severe Pollen Limitation In The Polychromic Tundra Plant, Parrya Nudicaulis (Brassicaceae), Justin R. Fulkerson, Justen B. Whittall, Matthew L. Carlson
Reproductive Ecology And Severe Pollen Limitation In The Polychromic Tundra Plant, Parrya Nudicaulis (Brassicaceae), Justin R. Fulkerson, Justen B. Whittall, Matthew L. Carlson
Biology
Pollen limitation is predicted to be particularly severe in tundra habitats. Numerous reproductive patterns associated with alpine and arctic species, particularly mechanisms associated with reproductive assurance, are suggested to be driven by high levels of pollen limitation. We studied the reproductive ecology of Parrya nudicaulis, a species with relatively large sexual reproductive investment and a wide range of floral pigmentation, in tundra habitats in interior montane Alaska to estimate the degree of pollen limitation. The plants are self-compatible and strongly protandrous, setting almost no seed in the absence of pollinators. Supplemental hand pollinations within pollinator exclusion cages indicated no cage …
Increased Floral Divergence In Sympatric Monkeyflowers, Dena L. Grossenbacher, Justen B. Whittall
Increased Floral Divergence In Sympatric Monkeyflowers, Dena L. Grossenbacher, Justen B. Whittall
Biology
Sympatric sister species are predicted to have greater divergence in reproductive traits than allopatric sister species, especially if mating system shifts, such as the evolution of self-fertilization, are more likely to originate within the geographic range of the outcrossing ancestor. We present evidence that supports this expectation-sympatric sister species in the monkeyflower genus, Mimulus, exhibit greater divergence in flower size than allopatric sister species. Additionally, we find that sympatric sister species are more likely to have one species with anthers that overtop their stigmas than allopatric sister species, suggesting that the evolution of automatic self-pollination may contribute to this pattern. …