Steven Woodard

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Eusociality has arisen independently at least 11 times in insects. Despite this convergence, there are striking differences among eusocial lifestyles, ranging from species living in small colonies with overt conflict over reproduction to species in which colonies contain hundreds of thousands of highly specialized sterile workers produced by one or a few(More)
The social insects live in extraordinarily complex and cohesive societies, where many individuals sacrifice their personal reproduction to become helpers in the colony. Identifying adaptive molecular changes involved in eusocial evolution in insects is important for understanding the mechanisms underlying transitions from solitary to social living, as well(More)
During the nest-founding phase of the bumble bee colony cycle, queens undergo striking changes in maternal care behavior. Early in the founding phase, prior to the emergence of workers in the nest, queens are reproductive and also provision and feed their offspring. However, later in the founding phase, queens reduce their feeding of larvae and become(More)
Pyruvate kinase is an important glycolytic enzyme which is expressed differentially as four distinct isozymes whose catalytic activity is regulated in a tissue-specific manner. The kidney isozyme is known to exhibit sigmoidal kinetics, whereas the muscle isozyme exhibits hyperbolic kinetic properties. By integration of the crystallographic [Stuart, D. I.,(More)
1,1-Dichloroethylene (DCE, 50 mg/kg) rapidly and selectively injures the bile canalicular membrane of zone 3 hepatocytes. Thus, DCE is of value as a tool to assess the consequences of alterations in canalicular membrane integrity on bile formation. Our objective was to characterize the effects of DCE on the biliary secretion of proteins and phospholipids in(More)
The occurrence of placental lactogens has been reported for members of 4 orders, 7 families, and 15 genera, while its absence has been documented in representatives from 4 orders, 5 families, and 5 genera. Placental lactogens from several genera have been isolated, purified, and characterized biochemically. The cellular sites of production and patterns of(More)
Sibling care is a hallmark of social insects, but its evolution remains challenging to explain at the molecular level. The hypothesis that sibling care evolved from ancestral maternal care in primitively eusocial insects has been elaborated to involve heterochronic changes in gene expression. This elaboration leads to the prediction that workers in these(More)
As increasingly large molecular data sets are collected for phylogenomics, the conflicting phylogenetic signal among gene trees poses challenges to resolve some difficult nodes of the Tree of Life. Among these nodes, the phylogenetic position of the honey bees (Apini) within the corbiculate bee group remains controversial, despite its considerable(More)
Bumble bees are a longstanding model system for studies on behaviour, ecology and evolution, due to their well-studied social lifestyle, invaluable role as wild and managed pollinators, and ubiquity and diversity across temperate ecosystems. Yet despite their importance, many aspects of bumble bee biology have remained enigmatic until the rise of the(More)
The apicoplast is an essential organelle of parasites in the phylum Apicomplexa, and has been the target for several clinically useful drugs to combat species such as Plasmodium, Toxoplasma and Cryptosporidium. Unfortunately, due to the increasing prevalence of drug resistance many of these treatments are being compromised. This research may provide a novel(More)