7) Nora Barlow, "The Inheritance of the Three Forms of the Trimorphic
Species," 13 (1923): 133-146.
In addition to the frequent loss of the M morph, trimorphic populations exhibited major departures from even morph frequencies.
Measures of reproductive success (expressed as mean [+ or -] 1 SE) obtained from marked plants in two trimorphic populations did not reveal a reproductive disadvantage to the M morph (Tables 3 and 4).
In addition to the loss of morphs from populations, stochastic processes are expected to increase the degree of morph-frequency variation among trimorphic populations.
Morph evenness in trimorphic populations increased significantly with population size (Fig.
salicaria population in southern Sweden (Andersson 1994), nor could it by itself explain deviations from even morph frequencies in trimorphic L.
To avoid empty cells (cannot be analyzed with the G-test), and for the expected frequency to be at least five in each cell, only data from trimorphic populations with 15 or more flowering plants were included in these analyses.
For Q slightly above 1, the dimorphic distribution is not stable, and we conjecture that, instead, the ESS is trimorphic for [Mathematical Expression Omitted] just above 1, followed by bifurcations to 5, 7, .
Local stability analysis confirms that for Q [less than] 1 and [Gamma] near 1 (as in [ILLUSTRATION FOR FIGURE 4 OMITTED]) the initial bifurcation is to an ESS with two alleles having equal but opposite phenotypic effects; hence, the population is dimorphic for haploid inheritance and trimorphic for diploid inheritance.
In spite of high self- and intramorph fertility, trimorphic populations typically outcross (Glover and Barrett 1986; Barrett and Husband 1990) with most outcrossed progeny resulting from intermorph matings (Barrett et al.
The experiments described below involved plants that were derived from a trimorphic population (B46: Barrett and Husband 1990) in Ceara state, northeastern Brazil.
We assessed the strength of drift in the simulations by monitoring the proportion of the 100 trimorphic
populations that remained trimorphic
versus nontrimorphic after 100 generations of mating.