Roger D. Price

Bio: Roger D. Price is an academic researcher from University of Minnesota. The author has contributed to research in topics: Menoponidae & Mallophaga. The author has an hindex of 12, co-authored 27 publications receiving 1059 citations. Previous affiliations of Roger D. Price include University of Oxford.

Comparative ecology of Neotropical bird lice (Insecta: Phthiraptera)

Abstract: Data are presented comprising the first quantitative survey of lice from Neotropical birds. The data were collected in the Andean foothills of south-eastern Peru using a novel scheme for quantitative sampling of ectoparasites from freshly killed hosts. In total, 685 birds representing 127 species in 26 families were sampled for lice; 327 (47.7%) birds were parasitized, with a mean intensity of 6.6 lice per bird and a mean richness of 1.1 louse species per host species. The bulk of variation in louse load was among host species nested within genera, although some variation occurred at higher taxonomic levels

The taxonomy of Geomydoecus (Mallophaga: Trichodectidae) from the Geomys bursarius complex (Rodentia: Geomyidae)

Abstract: A revision was undertaken of the members of the genus Geomydoecus parasitizing Plains Pocket Gophers of the Geomys bursarius complex. Prior to this revision, 5 specific and subspecific taxa of lice were recognized from Geomys bursarius . Approximately 20,000 lice were obtained and examined; these were from all described subspecies of G. bursarius and represented 590 individual hosts from 427 localities. In addition to a study of qualitative features, 28 morphological characters were quantified for both adult male and female lice. The measured or counted characters that proved useful taxonomically are reported along with their ranges, means, and standard deviations. Three programs in the BMDP series were used for the multivariate statistical analysis: principal components analysis (BMDP4M), discriminant function analysis (BMDP7M), and cluster analysis (BMDP2M). The Geomydocus on Geomys bursarius proved to be quite variable geographically; however, there was little intrapopulation variability. This geographical variation is best represented taxonomically by recognizing 8 distinct monotypic species of lice. The previously described species, Geomydoecus geomydis, G. ewingi, G. illinoensis , and G. oklahomensis , are all recognized as valid species. A population previously described as a subspecies of G. geomydis is elevated to specific status, G. subgeomydis , and 3 new species are described: G. heaneyi on Geomys bursarius llanensis and G. b. texensis; G. nebrathkensis on Geomys bursarius lutescens ; and G. spickai on Geomys bursarius missouriensis . These 8 species of lice cluster as 2 distinct groupings; the 1st, here termed the “northern” group, is composed of G. geomydis, G. illinoensis, G. nebrathkensis, G. oklahomensis , and G. spickai ; the 2nd, the “southern” group, is composed of G. ewingi, G. heaneyi , and G. subgeomydis . In no case did a single population of pocket gophers have more than 1 species of Geomydoecus parasitizing it. Two species of Geomydoecus were obtained on Long-tailed Weasels, Mustela frenata ; these host records are considered primary contamination, a result of the weasel's obtaining the lice directly from pocket gophers. A key is presented to the 15 specific and subspecific taxa of Geomydoecus that parasitize pocket gophers of the genus Geomys .

Comparative performance of species richness estimation methods.

Abstract: In most real-world contexts the sampling effort needed to attain an accurate estimate of total species richness is excessive. Therefore, methods to estimate total species richness from incomplete collections need to be developed and tested. Using real and computer-simulated parasite data sets, the performances of 9 species richness estimation methods were compared. For all data sets, each estimation method was used to calculate the projected species richness at increasing levels of sampling effort. The performance of each method was evaluated by calculating the bias and precision of its estimates against the known total species richness. Performance was evaluated with increasing sampling effort and across different model communities. For the real data sets, the Chao2 and first-order jackknife estimators performed best. For the simulated data sets, the first-order jackknife estimator performed best at low sampling effort but, with increasing sampling effort, the bootstrap estimator outperformed all other estimators. Estimator performance increased with increasing species richness, aggregation level of individuals among samples and overall population size. Overall, the Chao2 and the first-order jackknife estimation methods performed best and should be used to control for the confounding effects of sampling effort in studies of parasite species richness. Potential uses of and practical problems with species richness estimation methods are discussed.

Algal switching among lichen symbioses

Abstract: Lichens are intimate and long-term symbioses of algae and fungi. Such intimate associations are often hypothesized to have undergone long periods of symbiotic interdependence and coevolution. However, coevolution has not been rigorously tested for lichen associations. In the present study we compared the nuclear internal transcribed spacer (ITS) phylogenies of algal and fungal partners from 33 natural lichen associations to test two aspects of coevolution, cospeciation and parallel cladogenesis. Since statistically significant incongruence between symbiont phylogenies rejected parallel cladogenesis and minimized cospeciation events, we conclude that switching of highly selected algal genotypes occurs repeatedly among these symbiotic lichen associations.

Critical evaluation of five methods for quantifying chewing lice (Insecta: Phthiraptera).

Abstract: Five methods for estimating the abundance of chewing lice (Insecta: Phthiraptera) were tested. To evaluate the methods, feral pigeons (Columba livia) and 2 species of ischnoceran lice were used. The fraction of lice removed by each method was compared, and least squares linear regression was used to determine how well each method predicted total abundance. Total abundance was assessed in most cases using KOH dissolution. The 2 methods involving dead birds (body washing and post- mortem-ruffling) provided better results than 3 methods involving live birds (dust-ruffling, fumigation chambers, and visual examination). Body washing removed the largest fraction of lice ( .82%) and was an extremely accurate predictor of total abundance (r 2 5 0.99). Post-mortem-ruffling was also an accurate predictor of total abundance ( r2 $ 0.88), even though it removed a smaller proportion of lice (,70%) than body washing. Dust-ruffling and fumigation chambers removed even fewer lice, but were still reasonably accurate predictors of total abundance, except in the case of data sets restricted to birds with relatively few lice. Visual examination, the only method not requiring that lice be removed from the host, was an accurate predictor of louse abundance, except in the case of wing lice on lightly parasitized birds.

How Birds Combat Ectoparasites

Abstract: Birds are plagued by an impressive diversity of ectoparasites, ranging from feather-feeding lice, to feather- degrading bacteria. Many of these ectoparasites have severe negative effects on host fitness. It is therefore not surprising that selection on birds has favored a variety of possible adaptations for dealing with ectoparasites. The functional signifi- cance of some of these defenses has been well documented. Others have barely been studied, much less tested rigorously. In this article we review the evidence - or lack thereof - for many of the purported mechanisms birds have for dealing with ectoparasites. We concentrate on features of the plumage and its components, as well as anti-parasite behaviors. In some cases, we present original data from our own recent work. We make recommendations for future studies that could im- prove our understanding of this poorly known aspect of avian biology.