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CreatorTitleDescriptionSubjectDate
1 Seger, JonSexual dimorphism in the HymenopteraSpectacular sex differences of many kinds occur abundantly among the wasps, bees and ants that make up the insect order Hymenoptera. In some cases these differences are so extreme that males and females of the same species have been classified in different genera for decades, until a chance observa...Reproductive; Insect; Morphology1994
2 Seger, JonSolitary wasps: behavior and natural history by Kevin M. O'NeillMost species of living things are insects, and ter- restrial ecology consists largely of interactions between insects and plants. The biologies of major insect groups such as Hymenoptera should be well documented and well known. Amazingly, they are not. The world is awash in excellent reviews of cur...Insects; Ecological2002
3 Seger, JonConditional relatedness, recombination, and the chromosome numbers of insectsIf two polymorphic loci are out of phase equilibrium, a homozygote at one of these loci is more highly related to its kin, at the other locus, than is an equivalent heterozygote. As a result, selection can favor (1) phenotypic responses to relative heterozygosity, and (2) increased recombination bet...Coefficients of relatedness; Conditional relatedness1983
4 Seger, JonModels of sex ratio evolutionOur understanding of sex ratio evolution depends strongly on models that identify: (1) constraints on the production of male and female offspring, and (2) fitness consequences entailed by the production of different attainable brood sex ratios. Verbal and mathematical arguments by, among others, D...Fitness; Species; Sex-allocation2002
5 Davidson, Diane W.Tropical arboreal ants: why so abundant?ANTS ARE AMONG the most numerous and readily observed arthropods of tropical forests. Indeed, based on their standing biomass and many effects on other species, ants (Formicidae) are arguably the dominant arthropod family in the canopies of lowland rain forest trees (Tobin 1995). Others have tried t...Arboreal ants; Tropics1996
6 Seger, JonEvidence for a cryptic species complex in the ant parasitoid Apocephalus paraponerae (Diptera: Phoridae)Cryptic species complexes occur in many taxa, in particular in the insect order Diptera. Here we describe a possible new cryptic species complex in the family Phoridae. Three lines of evidence suggest that Apocephalus paraponerae, an ant parasitoid, is actually a complex of at least four genetically...Host; Sequence; Populations2001
7 Rees, Don M.A preliminary list of the ants of UtahThe following list of the ants of Utah was prepared from specimens and data now in the Biology Department of the University of Utah. This list is by no means complete, yet it is representative of practically all parts of the state. A few specimens in the collection date back to 1902, and all of thes...1940-11-05
8 Davidson, Diane W.Ant-plant symbioses in Africa and the neotropics : history, biogeography and diversitySymbiotic ant-plant relationships afford an excellent opportunity to analyze the effects of both historical and ecological factors on the evolution of mutualisms. Occurring in tropical forests throughout the world, all myrmecophytic plants provide food and permanent housing to ants; the ants, in t...Ant-plant symbiosis; Africa; Neotropics; Myrmecophytes; Plant-ants1993
9 Seger, JonIdeas in ecologyThe word "ecology" means different things to different people. For example, during the last 25 years or so the word has been used to label attitudes, life-styles, consumer goods, political parties, and college courses. In the 1960s one university renamed its "Home Economics" course "Home Ecology."...Behavioral ecology; Population ecology1986
10 Sekercioglu, CaganLandscape constraints on functional diversity of birds and insects in tropical agroecosystemsIn this paper, we analyze databases on bird and insects to assess patterns of functional diversity in human-dominated landscapes in the tropics. Perspective from developed landscapes is essential for understanding remnant natural ecosystems, because most species experience their surroundings at spat...2008-01-01
11 Bohs, Lynn A.Solanum maternum (Solanaceae), a new Bolivian relative of the tree tomatoA new species endemic to Bolivia, Solanum maternum, is described. Solanum maternum belongs to a group of taxa formerly recognized as the genus Cyphomandra. Solanum maternum is morphologically very similar to the tree tomato, Solanum betaceum, and may be its closest wild relative.Solanum maternum; Cyphomandra1997
12 Adler, Frederick R.Balance of terror: an alternative mechanism for competitive trade-offs and its implications for invading speciesThis article uses models to propose an explanation for three observations in community ecology: the apparent overreaction of prey to attack by specialist predators, the existence of a common trade-off among components of competitive ability in communities of unrelated competitors, and the ability of...Models; Curve; Native1999
13 Adler, Frederick R.; Feener, Donald H.Maintaining diversity in an ant community: modeling, extending, and testing the dominance-discovery trade-offAnt communities often consist of many species with apparently similar niches. We present a mathematical model of the dominance-discovery trade-off, the trade-off between the abilities to find and to control resources, showing that it can in principle facilitate the coexistence of large numbers of s...Coexistence; Dominant species; Parasitoid2007
14 Davidson, Diane W.Experimental studies of species-specificity in cecropia-ant relationshipsStrict coevolution requires that interactions among organisms be speciesspecific. We assessed the relative roles of host- and habitat-specificity in determining the match between a genus of myrmecophytic trees and a guild of obligate plant-ants in the moist tropical forests of Madre de Dios, Peru. F...Ant-plant; Ants; Cecropia; Coevolution; Colonization; Coordinated dispersal; Ecological fitting; Habitat-specificity; Host-specificity; Mutualism; Parasitoid wasps; Preadaptation1997
15 Coley, Phyllis D.Red coloration of tropical young leaves: a possible antifungal defense?Many woody species in humid tropical forests synchronously flush entire canopies of young red leaves. Numerous unsuccessful attempts have been made to explain the adaptive value of this visually striking phenomenon. In the humid tropics, fungal attack is a potentially important source of mortality f...Herbivory; Anthocyanin; Antifungal defense; Atta columbica; Panama; Leaf-cutting ants; Tropics; Young leaves1989
16 Seger, JonIntraspecific resource competition as a cause of sympatric speciation[In most models of speciation], the fitness value of an animal is determined by the genotype it has, and the habitat in which it lives. In a more realistic model it should also depend on how much necessary resource is available for the animal and the competition from other genotypes for this resourc...Phenotype; Models; Species1985
17 Davidson, Diane W.Size variability in the worker caste of a social insect (veromessor pergandei mayr) as a function of the competitive environmentWorker size polymorphism in colonies of Veromessor pergandei, a granivorous desert ant, is inversely related to the intensity of interspecific competition in the habitat for seven ant communities in the deserts of southern California and southern Arizona. Seed size preferences are positively corr...Ants; Arizona; California; Coexistence; Communities; Density specialization; Desert granivores; Foraging strategies; Resource partitioning; Size1978
18 Bohs, Lynn A.Phylogeny of the Cyphomandra clade of the genus Solanum (Solanaceae) based on ITS sequence data13 major clades can be recognized within the genus Solatium (Solanaceae) based on chloroplast DNA sequence data. One of these is the Cyphomandra clade, which includes about 50 neotropical species. These have traditionally been placed into two or three sections: S. section Pachyphylla (formerly recog...Cyphomandra; ITS; osmophores; self-incompatibility; Solanum2007
19 Davidson, Diane W.Dispersal adaptations of some acacia species in the Australian arid zoneMost Australian representatives of the genus Acacia have diaspores with arillate appendages indicative of adaptation for active dispersal by animals. Based on physical and chemical characteristics of these arils and mechanisms of diaspore presentation, a number of arid zone acacias can be distingu...Acacia; Australian arid zone; Dispersal ecology; Fruit quality; Myrmecochory; Ornithochory; Seed parasitoids; Soil nutrients1984
20 Adler, Frederick R.Virulence management in biocontrol agentsAlthough biological control is founded upon the virulence of natural enemies to the targeted pests, there has been little effort to understand how this might change, let alone to manage it. Frank Fenner and colleagues can be credited with being the first (and last!) to monitor changes in virulence ...Pathogens; Management; Natural2002
21 Davidson, Diane W.Ecological studies of neotropical ant-gardensIn a census taken in Peru's Manu National Park, 10 epiphytic angiosperms from seven plant families established principally on arboreal carton-ant nests. These "ant gardens" (AGs) were most often inhabited by parabiotic ants, Camponotus femoratus and Crematogaster cf. limata parabiotica, whose polygy...Ant competition; Ant garden; Ant-plant interaction; Coadaptation; Epiphyte; Mutualism; Parabiosis; Preadaptation; Peru; Seed dispersal; Tropical rainforest1988
22 Adler, Frederick R.How virulent should a parasite be to its vector?Vector-borne parasites are commonly predicted to be less virulent to the vector than to the definitive host as the parasite gains little by harming its main route of transmission. Here we assess the empirical evidence from systems in which insects are vectors for vertebrate, plant, and invertebrate ...Parasite virulence; Hosts; Vector-borne parasite2003
23 Davidson, Diane W.Pruning of host plant neighbors by ants: an experimental approachSome ants of myrmecophytic plants either obligately or facultatively prune vegetation surrounding their host trees. Pruning behavior occurs at higher frequency in ants with sting defenses than in those with chemical defenses, which may generally convey an advantage in aggressive encounters between a...Allelopathy; Allomerus demararae; Ant-plant interactions; Ants; Cordia nodosa; Crematogaster; Mutualism; Peru; Plant-animal interaction; Pseudomyrmex; Triplaris americana1988
24 Davidson, Diane W.; Rickart, Eric Allan; Keiter, Robert B.Selecting wilderness areas to conserve Utah's biological diversityCongress is currently evaluating the wilderness status of Bureau of Land Management (BLM) public lands in Utah. Wilderness areas play many important roles, and one critical role is the conservation of biological diversity.Bureau of Land Management; Conservation; Endemic species; Exotic species; Cryptobiotic soils; Plants; Bees; Vertebrates1996
25 Bohs, Lynn A.Crossing studies in Cyphomandra (Solanaceae) and their systematic and evolutionary significanceA crossing program involving eight species of Cyphomandra was instituted to elucidate systematic relationships between the taxa and evolutionary mechanisms operating in the genus. The results show that gametophytic self-incompatibility is widespread in Cyphomandra. Pollen tubes were able to reach ...Solanum maternum; Crossing studies1991
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