Other examinations of the association between plant characteristi

Other examinations of the association between plant characteristics and rarity have generally categorized rarity on only a single axis, or have used IUCN red list criteria (Bekker and Kwak 2005). Single-axis approaches have either (1) categorized species as either “abundant” or not, utilizing

the axes of GR and LA interchangeably (Kunin and Gaston 1993; Hegde and Ellstrand 1999), (2) developed a single rarity index utilizing endemism, GR, and endangerment status (Farnsworth 2007), or (3) used GR (Thompson et al. 1999; Lester et al. 2007; Gove et al. 2009; Leger and Forister 2009). The IUCN red list combines population size, growth rate, population fluctuation, habitat Wortmannin fragmentation, and range size into an endangerment index (IUCN 2001). A previous, trait-based meta-analysis combining the three rarity axes (Murray et al. 2002) found a very limited number of studies that MS-275 in vitro encompassed more than one axis of rarity. Although the separation of rarity into different types is controversial (Kunin and Gaston 1993; Hegde and Ellstrand 1999), we conducted this study to determine if the research resulting from the widespread use of this matrix learn more supports the separation of rarity into different syndromes. While plant species distributions may reflect basic

demographic processes of seed production, dispersal, and establishment, the distribution of species may also in itself be GNAT2 a selective force and affect evolutionary trajectories. For example, species that grow in locally abundant populations may evolve to tolerate intraspecific competition better than interspecific competition (Rabinowitz et al. 1984; Rabinowitz and Rapp 1985). Species of locally sparse populations may be highly dependent on pollinators to ensure reproduction when non-autogamous. Species with large GR have been found

to be better colonizers (Leger and Forister 2009), and colonization ability may in turn be selected for in these species. Assuming equilibrium conditions in species distributions, once there is a fitness advantage to reproducing and dispersing within the current distribution, it is reasonable to predict adaptation to the biological and ecological conditions of the distribution itself (Morris 2003). We presume species persist in their current distribution pattern because they have historically succeeded that distribution pattern. This presumption is heavily relied upon to predict trajectories of plant invasions (e.g. Higgins et al. 1999; Thuiller et al. 2005) and may be applicable to native short-lived species. Distributions of longer-lived species, such as trees and perennial grasses, may reflect land use history (e.g. Palo et al. 2008) or previous climate (Kruckeberg and Rabinowitz 1985). Factors that once determined establishment of these species may no longer be present although factors that affect mortality are very likely still in action.

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