William Kemp

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The evolution of eusociality is one of the major transitions in evolution, but the underlying genomic changes are unknown. We compared the genomes of 10 bee species that vary in social complexity, representing multiple independent transitions in social evolution, and report three major findings. First, many important genes show evidence of neutral evolution(More)
We propose a class of complex population dynamic models that combines new time-varying parameters and second-order time lags for describing univariate ecological time series data. The Kalman filter and likelihood function were used to estimate parameters of all models in the class for 31 data sets, and Schwarz's information criterion (SIC) was used to(More)
A study was conducted to evaluate differences in rangeland grasshopper communities over environmental gradients in Gallatin Valley, Montana, USA. The concept of habitat type (Daubenmire 1966) was used as a basis for discriminating between groupings of patches based on vegetation. A total of 39 patches were selected that represented five recognized grassland(More)
Osmia (Osmia) bees are strictly univoltine and winter as diapausing adults. In these species, the timing of adult eclosion with the onset of wintering conditions is critical, because adults exposed to long pre-wintering periods show increased lipid loss and winter mortality. Populations from warm areas fly in February-March and are exposed to longer growth(More)
We tested for the existence of density dependence in annual adult rangeland grasshopper (Orthoptera: Acrididae) data from Montana, USA (1951-1991). Statistical density dependence was, in the sense of a stochastic equilibrium or return tendency, detected in all of the grasshopper mean density time-series from the three major physiographic regions of the(More)
Olfactory cues and nest recognition in the solitary bee Osmia lignaria" (2006). Entomology Papers from Other Sources. Paper 72. Abstract. The use of olfactory cues for nest recognition by the solitary bee Osmia lignaria is studied in a greenhouse environment. Glass tubes are provided as nesting cavities to allow the in-nest behaviour of bees to be observed.(More)
We addressed the importance of third dimension and color contrast as cues used in close range nest localization by Osmia lignaria Say and Megachile rotundata (F.) females. By manipulating the surface of the nesting site, we compared 3-dimensional configurations of three different depths (1 cm, 2 cm, and 6 cm) and three different color contrasts(More)
The cuticular lipids of the cavity-nesting adult female solitary bees, Osmia lignaria Say and Megachile rotundata (F.) (Hymenoptera: Megachilidae), were analyzed by gas chromatography (GC) and combined GC-mass spectrometry. The cuticular lipids of these female bees are mainly consisted of hydrocarbons. For O. lignaria, nearly 64% of the cuticular lipids(More)
We construct a mathematical model to quantify the loss of resilience in collapsing honey bee colonies due to the presence of a strong Allee effect. In the model, recruitment and mortality of adult bees have substantial social components, with recruitment enhanced and mortality reduced by additional adult bee numbers. The result is an Allee effect, a net(More)
Metamorphosis is an important developmental stage for holometabolous insects, during which adult morphology and physiology are established. Proper development relies on optimal body temperatures, and natural ambient temperature (Ta) fluctuations, especially in spring or in northern latitudes, could result in interruptions to development. It is unclear how(More)