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Abstract

There is now a large body of evidence which indicates that populations of plants and animals contain great amounts of genetic variability (e.g., Dempster, 1955;Dobzhansky, 1955), and the elucidation of the factors which maintain this variability within populations is one of the main problems confronting population genetics today (e.g., Allard and Jain, 1962;Dobzhansky, Spassky, and Tidwell, 1963;Wallace, 1963). One requirement for the solution of this problem is adequate data concerning the magnitude and nature of the genetic variability contained within populations. However, despite the extensive work which has been done in plant evolution and plant population genetics, there appear to be no precise estimates for quantitative characters of the genetic variability within individual populations of any naturally occurring plant species.The most extensive data concerning quantitative variability within individual natural plant populations appear to be those of Baker (1957) for Geranium purpureum. From experimental field plantings made over several years, Baker determined between plant phenotypic variance for several 1

Description and biology of two new egg parasitoid species (Hymenoptera: Trichogrammatidae) reared from eggs of Heliconiini butterflies (Lepidoptera: Nymphalidae: Heliconiinae) in Panama

“…The passion-vine or longwing butterflies belonging to the tribe Heliconiini (Lepidoptera: Nymphalidae: Heliconiinae), which comprise Heliconius Kulk and related genera, are a highly diverse group of butterflies from the Neotropics (Brown 1981;Gilbert 1991;Harvey 1991;Penz and Peggie 2003). Heliconiini butterflies are important model organisms for unravelling the coevolution between insects and their host plants (Ehrlich and Raven 1964;Brown 1981 used exclusively as host plants for their caterpillars (Benson et al 1975;Brown 1981). Eggs are typically brightly coloured and laid singly or in (small) groups on new shoots, tendrils or older leaves (Benson et al 1975;Brown 1981).…”

Contrasting patterns of Andean diversification among three diverse clades of Neotropical clearwing butterflies

“…A diversity of environmental and ecological conditions provides multiple opportunities for adaptation and ecological speciation. The distribution of poikilotherm phytophagous insects for example will be directly determined by temperature, rainfall, and solar radiation (e.g., Menéndez et al, 2007), as well as by the plant community that hosts their larval stages and that is known to also act as an important driver of diversification (Ehrlich & Raven, 1964;Janz, Nylin, & Wahlberg, 2006). From a biogeographic point of view, mountain ranges not only generate local diversification along their slopes, but they can also feed adjacent areas through dispersal events, potentially enhancing diversification in neighboring regions.…”