| surveillance for ixodes pacificus and the tick-borne pathogens anaplasma phagocytophilum and borrelia burgdorferi in birds from california's inner coast range. | we investigated the involvement of birds in the ecology of the western black-legged tick, ixodes pacificus, and its associated zoonotic bacteria, borrelia burgdorferi and anaplasma phagocytophilum, at two interior coast-range study sites in northern california. anaplasma phagocytophilum, the agent of granulocytic anaplasmosis (ga), and b. burgdorferi s.s., the agent of lyme disease (ld), are tick-borne pathogens that are well established in california. we screened blood and ticks from 349 indivi ... | 2014 | 24690191 |
| avian hosts of ixodes pacificus (acari: ixodidae) and the detection of borrelia burgdorferi in larvae feeding on the oregon junco. | larval and nymphal western blacklegged tick, ixodes pacificus cooley & kohls (acari: ixodidae), were collected from birds, rodents, and lizards at quail ridge reserve located in napa county in northwestern california. species from three vertebrate classes were sampled simultaneously from two transects during two consecutive spring seasons. feeding larval and nymphal ticks were removed and preserved for counting, examination and testing for the presence of borrelia burgdorferi johnson, schmid, hy ... | 2011 | 21845945 |
| hormonal, behavioral, and life-history traits exhibit correlated shifts in relation to population establishment in a novel environment. | climate change, habitat alteration, range expansions, and biological invasions are all predicted to require rapid shifts in multiple traits including behavior and life history, both for initial population establishment and subsequent adaptation. hormonal mechanisms likely play a key role in facilitating or constraining plastic and genetic responses for suites of traits, but few studies have evaluated their role in shaping contemporary adaptation or diversification. we examined multiple phenotypi ... | 2014 | 25438184 |
| genetic and morphological evolution following a founder event in the dark-eyed junco, junco hyemalis thurberi. | an isolated population of dark-eyed juncos, junco hyemalis, became established on the campus of the university of california at san diego (ucsd), probably in the early 1980s. it now numbers about 70 breeding pairs. populations across the entire natural range of the subspecies j. h. thurberi are weakly differentiated from each other at five microsatellite loci (fst = 0.01). the ucsd population is significantly different from these populations, the closest of which is 70 km away. it has 88% of the ... | 2004 | 14871370 |
| rapid evolution of a sexually selected trait following population establishment in a novel habitat. | colonization of novel environments creates new selection pressures. sexually selected traits are affected by the physical and social environment and should be especially susceptible to change, but this has rarely been studied. in southern california, dark-eyed juncos, (junco hyemalis) naturally breed in mixed-coniferous temperate forests, typically from 1500 m to 3000 m in elevation. in the early 1980s, a small population became established in a coastal habitat, the university of california, san ... | 2004 | 15058729 |
| phenotypic plasticity and the evolution of a socially selected trait following colonization of a novel environment. | novel selection pressures in new environments arise through two distinct processes. first, environmental conditions directly affect the fitness of different phenotypes. second, phenotypic plasticity alters the distribution of phenotypes, thereby placing populations in new selective regimes. a small isolated population of dark-eyed juncos junco hyemalis became established in san diego, probably in the early 1980s and probably from the nearby mountains. the relatively mild coastal climate has resu ... | 2008 | 18554144 |