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CreatorTitleDescriptionSubjectDate
226 Clayton, Dale H.; Rogers, Alan R.Genetic analysis of lice supports direct contact between modern and archaic humansParasites can be used as unique markers to investigate host evolutionary history, independent of host data. Here we show that modern human head lice, Pediculus humanus, are composed of two ancient lineages, whose origin predates modern Homo sapiens by an order of magnitude (ca. 1.18 million years).Pediculus humanus; Head lice; Molecular phylogeny; Phthirus2004
227 Adler, Frederick R.Genetic and phylogenetic consequences of island biogeographyIsland biogeography theory predicts that the number of species on an island should increase with island size and decrease with island distance to the mainland. These predictions are generally well supported in comparative and experimental studies. These ecological, equilibrium predictions arise as a...Extinction; Genetic divergence; Island isolation; Migration; Speciation2000
228 Shapiro, Michael D.Genetic architecture of parallel armor plate reduction in threespine sticklebacksHow many genetic changes control the evolution of new traits in natural populations? Are the same genetic changes seen in cases of parallel evolution? Despite long-standing interest in these questions, they have been difficult to address, particularly in vertebrates. We have analyzed the genetic bas...Genetic changes; Plate number; Genetic mapping2004
229 Shapiro, Michael D.Genetic architecture of skeletal convergence and sex determination in ninespine sticklebacksThe history of life offers plentiful examples of convergent evolution, the independent derivation of similar phenotypes in distinct lineages [1]. Convergent phenotypes among closely related lineages (frequently termed "parallel" evolution) are often assumed to result from changes in similar genes or...Convergent evolution; Skeletal convergence; Pungitius pungitius; Gasterosteus aculeatus; Comparative genetics2009-07
230 Capecchi, Mario R.Genetic interaction between hoxb-5 and hoxb-6 is revealed by nonallelic noncomplementation.hoxb-5 and hoxb-6 are adjacent genes in the mouse HoxB locus and are members of the homeotic transcription factor complex that governs establishment of the mammalian body plan. To determine the roles of these genes during development, we generated mice with a targeted disruption in each gene. Three ...Alleles; CCAAT-Enhancer-Binding Proteins; Cervical Vertebrae; DNA-Binding Proteins; Forelimb; Genetic Complementation Test1995-01-01
231 Jorgensen, ErikGenetic screens for synaptic function mutants in the nematode C. elegansThe synapse is the site of a remarkable conversion of electrical signals into chemical signals. This conversion takes place when a depolarizing impulse enters the axon terminal and opens voltage-sensitive calcium channels; calcium then flows into the cell and initiates the fusion of synaptic vesicle...Vesicle; Neurotransmission; Cell1996
232 Rogers, Alan R.; Harpending, Henry C.Genetic structure of ancient human populationsDiscusses mitochondrial DNA (mtDNA) sequences as important source of data about the history of human species.Tree of descent; Mismatch distributions; Simulations; Findings; Intermatch distributions; Younger and older populations2001-09-15
233 Parkinson, John StansfieldGenetics of bacterial chemotaxisMany types of motile bacteria are capable of detecting and responding to changes in their environment. Phototactic, chemotactic and thermotactic movements in bacteria are similar to more complex behaviours seen in higher organisms, and constitute useful model systems for investigating the molecular ...Bacterial chemotaxis1981
234 Potts, Wayne K.Gong method for capturing shorebirds and other ground-roosting speciesIn many shorebird studies it is necessary to capture adult birds. While shorebirds can often be trapped on the nest, capturing them away from the nest is usually very difficult and may require expensive equipment. After weeks of failure in our attempts to capture migrant and resident shorebirds in n...Gong method; Shorebirds; Capture; Ground-roosting1979
235 Davidson, Diane W.Granivory in a desert ecosystem: experimental evidence for indirect facilitation of ants by rodentsTwo major groups of desert granivores, ants and rodents, coexist as permanent residents of local desert habitats in southwestern North America. At our Sonoran Desert study site, both of the major taxa exhibited short-term increase in density when the other taxon was experimentally removed. Over the...Ants; Arizona; Desert annuals; Facilitation; Granivory; Indirect mutualism; Rodents; Seed predation; Sonoran Desert1984
236 Davidson, Diane W.Granivory in the Chihuahuan Desert: interactions within and between trophic levelsWe investigated the effects of Chihuahuan Desert granivores on three seasonal classes of plant resource species, the effects of these resource classes on one another, and the ways in which interactions through plant resources affect the abundances of seed consumers. At our study site, three seasona...Annual plant; Ant; Competition; Community; Desert; Ecosystem structure; Experiment; Granivore; Indirect interaction; Rodent; Population cycles; Seed predation1985
237 Davidson, Diane W.Granivory in the Chihuahuan desert: interactions within and between trophic levelsWe investigated the effects of Chihuahuan Desert granivores on three seasonal classes of plant resource species, the effects of these resource classes on one another, and the ways in which interactions through plant resources affect the abundances of seed consumers. At our study site, three seasona...Annual plant; Ant; Competition; Community; Desert; Ecosystem structure; Experiment; Granivore; Indirect interaction; Rodent; Population cycles; Seed predation1985
238 Bastiani, MichaelGrowth cone dynamics during the migration of an identified commissural growth coneWe have used time-lapse video microscopy to study the behavior of a neuron, 01, that pioneers the posterior commissure of the embryonic grasshopper. Our goal is to use time-lapse video as a tool to acquire a precise picture of normal development over time, and thereby identify stereotypic activities...Time-lapse video; Commissure; Grasshopper; Pathfinding; Filopodia; Confocal microscopy; Adhesion1993
239 Coley, Phyllis D.Growth-defense trade-off and habitat specialization by plants in Amazonian forestsTropical forests include a diversity of habitats, which has led to specialization in plants. Near Iquitos, in the Peruvian Amazon, nutrient-rich clay forests surround nutrient-poor white-sand forests, each harboring a unique composition of habitat specialist trees. We tested the hypothesis that t...Amazon; Ecological gradient; Growth-defense trade-off; Habitat specialization; Herbivory; Phenolics; Phylogenetic control; Rainforest; Reciprocal-transplant experiment; Terpenes; Tropical trees2006
240 Ehleringer, James R.Grupos funcionales en arbustos deserticos del norte de Chile, definidos sobre la base de las fuentes de agua utilizadasLa productividad primaria y la estructura de la vegetación en ecosistemas áridos están determinadas por la disponibilidad de agua. En un estudio realizado en el secano costero del norte-centro de Chile (29/43'S; 71/14'O, 300 m) se compararon los mecanismos de utilización de distintas fuentes de...Grupos funcionales; Functional groups; Arbustos deserticos; Desert shrubs; Fuentes de agua; Water sources; Water availability; Arid ecosystems; Pastoreo con caprinos; Goat overgrazing1999-01-01
241 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. I. Recognition of a specific axonal pathway by the pCC neuronThe selective affinities that growth cones display for specific axonal surfaces give rise to stereotyped patterns of selective fasciculation. Previous studies on cell recognition by neuronal growth cones in the grasshopper embryo led to the proposal and initial experimental testing of the labeled-p...Fascicle; Axon; Affinity1986
242 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. II. Recognition of a specific axonal pathway by the aCC neuronIn the previous paper, we experimentally analyzed the selective affinity of the pCC growth cone for the MP1/dMP2 fascicle in the grasshopper embryo. Here we describe a similar experimental analysis demonstrating the selective affinity of the aCC growth cone for the U fascicle. These results support...Axon; Cell; Fascicle1986
243 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. III. Recognition of specific glial pathwaysIn the previous 2 papers, we focused on the selective affinities that growth cones display for specific axonal pathways. Little is known, however, about how this orthogonal scaffold of axonal pathways in the CNS is established in the first place, and what, if any, role glia might play in these even...CNS; Nerve; Cells1986
244 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. IV. Temporal delay experimentsIn the previous 3 papers, we demonstrated that neuronal growth cones display selective affinities for both specific axonal and glial pathways in the grasshopper embryo; for example, the pCC growth cone selectively recognizes the MPl/dMP2 axons, while the aCC growth cone selectively recognizes the U...Pathways; Neurons; Axons1986
245 Bastiani, MichaelGuidance of neuronal growth cones: selective fasciculation in the grasshopper embryoOne of the central questions of developmental neurobiology concerns how the diversity and specificity of individual neurons are generated during embryonic development. One major component of neuronal diversity is the complex axonal morphology of individual neurons, largely generated early in develop...Neurons; Filopodia; Axon1983
246 Coley, Phyllis D.Guía de los arboles comunes del Parque Nacional Soberanía, PanamáEsta es una guía con dibujos para las cincuenta especies de árboles más comunes del bosque tropical en los alrededores del Parque Soberanía, Panamá. También se incluyen siete especies de hierbas y cuatro herbáceas grandes que sobresalen en el sotobosque (bosque bajo). Aunque en el área del p...Arboles; Arbustos1984
247 Sekercioglu, CaganHabitat use and movements of native forest birds in southern Costa Rican agricultural countrysideWe used radio telemetry to study the habitat use, activity budgets, and movements of three bird species that are found in native forest and coffee plantations of southern Costa Rica. We obtained 7522 locations from Turdus assimilis (n=27), Tangara icterocephala (n=53), and Catharus aurantiirostris (...2003-01-01
248 Parkinson, John StansfieldHAMP domain structural determinants for signalling and sensory adaptation in Tsr, the E. coli serine chemoreceptorMotile Escherichia coli cells track chemical gradients with high sensitivity over wide concentration ranges [recently reviewed in (Hazelbauer et al., 2008; Hazelbauer & Lai, 2010)]. Stimulus detection, amplification, and integration occur in an arrayed network of signaling complexes that contain tra...2014-01-01
249 Capecchi, Mario R.Hematopoietic origin of pathological grooming in Hoxb8 mutant miceMouse Hoxb8 mutants show unexpected behavior manifested by compulsive grooming and hair removal similar to humans with OCD-spectrum disorder trichotillomania. Since Hox gene disruption often has pleiotropic effects, the root cause of this behavioral deficit was unclear. Here we report that, in the b...2010
250 Coley, Phyllis D.Herbivory and defensive characteristics of tree species in a lowland tropical forestRate of herbivory and defensive characteristics of young and mature leaves were measured for saplings of 46 canopy tree species in a lowland tropical rain forest (Barro Colorado Island, Panama). Grazing rates were determined in the field for sample periods in the early wet, late wet, and dry seasons...Fiber; Herbivory; Life history; Panama; Phenolics; Plant growth; Spatial distribution; Tannins; Temporal distribution; Treefall gaps; Tropical forest1983
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