bluuebunny/crossref_metadata_2025 huggingface dataset:
Structuring ward rounds for learning: can opportunities be created?
Authors: Stanley Paula
Published: March 2003

This paper explores the ways in which ward rounds can be conducted to maximize educational opportunities, as part of a project to improve the effectiveness of on‐the‐job training (OJT) for hospital doctors. Ninety ward rounds taken by 24 trainers in the Anglia region were observed. Each observation produced a note of the ward round's structure and routines and of the contributions made to it by trainers and trainees. Teaching was a feature of all ward rounds and different types of round were valued for different reasons. A range of ward round structures was observed and, within each, a range of routines for conducting the round. Ward round structures fell into four categories, with almost three‐quarters of trainers making no use of either pre‐ or post‐ward round meetings. Where such meetings took place, however, opportunities for OJT were created and, in some cases, optimized through routines to encourage trainee contributions. Discussion time away from patients structured into ward rounds enabled trainers and trainees to take advantage of many opportunities to learn from service. Although unplanned and unsystematic opportunities for OJT do arise, far more reliable are those created through systematic planning and preparation. Trainers have choices to make about how they conduct ward rounds and by choosing to make use of pre‐ and/or post‐ward round sessions, valuable opportunities for OJT can be created.
Who should assess medical students' communication skills: their academic teachers or their patients?
Authors: Cooper Chris , Mira Michael
Published: March 2003

The objective of this study was to compare the assessment of medical students communication skills made by their academic teachers, with the assessment made by their role‐playing `patients'. It was a cross‐sectional study, conducted at the Department of General Practice, University of Sydney, Australia, and consisted of 519 undergraduate medical students. Teachers rated students' communication skills using ten specific criteria, each marked on a five‐point Likert scale. Teachers then rated students' overall performance using a 10‐point scale. Patients rated students' overall performance on the same 10‐point Likert scale. Only two of the 10 criteria, as rated by the academic teachers, correlated with the role‐playing patients' overall score, and all 10 criteria accounted for only 10·1% of the variance in that score. The academic assessors' overall score accounted for only 9·7% of the variance of the patients' overall score. The communications skills emphasized by academic teachers do not reflect the skills considered to be important by role‐playing patients.
Does a student log provide a means to better structure clinical education?
Authors: Dolmans  , Schmidt  , Van Der Beek  , Beintema  , Gerver
Published: March 2003

Context

In order to optimize student learning during clinical rotations, the learning situation could be better structured. A student log was developed in order to improve the structure of clinical education. In this log, students systematically register essential learning activities. Students record daily the patient problems with which they had been confronted and in which fashion (passive, active, without or with feedback).

Objectives/research questions

Two questions were addressed. Firstly, did the log provide insight into the content and nature of students' learning experiences and did these learning experiences differ between hospitals? Secondly, was the log used by students, supervisors and the faculty to improve the structure of student learning during clinical education?

Method

Three student logs, used in an ear, nose and throat, an ophthalmology and a paediatrics clerkship at the Medical School of the University of Maastricht, were developed and implemented. In order to answer the first question, a number of completed student logs were analysed. In order to answer the second question, students were asked to rate the log on five evaluative statements. In addition, the clerkship coordinators were interviewed.

Results

The results showed that the logs provided the clerkship coordinators with a useful overview of the content and nature of students' learning experiences in the hospitals. The differences between hospitals were small. However, the logs were not used by students, supervisors and faculty to improve the structure of student learning.

Conclusions

In order to be effective, i.e. to better structure clinical education, a student log should be integrated into the supervision activities.
Factors associated with success or failure in radiological interpretation: diagnostic thinking approaches
Authors: Peterson Cynthia
Published: March 2003

Rationale and objectives

To identify those radiological diagnostic thinking approaches associated with success or failure in film interpretation.

Methods

A questionnaire was designed, piloted and tested for validity and reliability prior to use. This questionnaire was adapted and modified from the `diagnostic thinking inventory' by Bordage et al. 21 One hundred and eighty students anonymously answered the questionnaire prior to their 15‐case comprehensive film interpretation examination. Oral film‐reading sessions were performed on a stratified random sample (n = 48) of students with complete transcripts of each session recorded. Spearman's correlation coefficient and multiple regression analysis statistics were applied to the questionnaire data. The unpaired t‐test,
ANOVA and correlation statistics were used to analyse the oral film‐reading sessions.

Results

The most successful students were those who could easily see the integration of radiology with other subjects (P = 0·0042), students who could easily link the clinical information to the radiographic signs (P = 0·0354), and students who could easily identify the `key' abnormal radiographic findings (P = 0·047). Students who used a flexible but complete search pattern performed significantly better (P = 0·0235) than students using any other search pattern approach.

Conclusions

Radiology is a classic example of clinical problem solving and thus should be taught in that format. Those same factors which differentiate expert from novice diagnosticians are also evident in more successful vs. less successful students in radiology.
The core content of the undergraduate curriculum in Manchester
Authors: O'Neil  , Metcalfe  , David
Published: March 2003

Aim

To identify the core content for the new undergraduate medical curriculum in Manchester.

Method

The initial step was to produce a list of `index clinical situations' (ICSs), for which a newly graduated doctor must have a required level of competence. Using repeated consultation with consultants and general practitioners involved in medical education in the North‐West of England, a list of 215 ICSs was agreed. Specialists and generalists were then asked to identify the components of the knowledge base and the performance (skills) base for each ICS. The knowledge base was divided into technical (biomedical facts/concepts) and contextual (effect/management of disease within the individual, family and society) domains. The performance base was divided into intellectual (problem solving and decision making) and interpersonal (history, examination, communication and procedural skills) domains.

Results

Forty specialities were consulted and 11 021 items (defined as a piece of knowledge, a concept or a skill) were identified. There was considerable overlap in the items listed, such that when the returns for each ICS were amalgamated, the 215 ICSs contained 6434 items with a mean of 34 ± 14·2 per situation (range 6–85).

Utilisation

We have used the defined ICSs in the design of the trigger material used in the weekly problem‐based learning sessions. Over 4 years almost all (207/215, 96%) of the ICS are covered, with many being revisited at several points in the curriculum.
DNA fingerprinting evidence of nonfilial nursing in grey seals
Authors: PERRY ELIZABETH A. , BONESS DARYL J. , FLEISCHER ROBERT C.
Published: March 2003

We tested the hypothesis that kin selection may play a role in fostering behaviour in grey seals. Fostering frequency varied among three colonies, ranging from 3% to 28%. Band‐sharing coefficients (S) of DNA fingerprints, from two multilocus probes, were used to predict relatedness (r). Mean r did not differ between foster mother‐pup pairs and the expected r = 0 for presumed unrelated female‐pup pairs. Likewise, mean r between fostered and filial pups compared to r between presumed unrelated pups within the same beaches did not differ. Mean S values of presumed unrelated pups on different beaches within the two smallest colonies were indistinguishable, indicating that there is not increased variation in relatedness in small colonies. These results suggest that kin selection does not play a significant role in the maintenance of grey seal fostering behaviour.
Dispersal, philopatry, and genetic relatedness in a social carnivore: comparing males and females
Authors: GOMPPER M. E. , GITTLEMAN J. L. , WAYNE R. K.
Published: March 2003

A balance must be maintained between the proportion of individuals dispersing and the proportion remaining philopatric such that inbreeding and resource competition are minimized. Yet the relative importance of dispersal and philopatric behaviour is uncertain, especially for species with complex social systems. We examine the influence of dispersal on genetic relationships of a white‐nosed coati (Nasua narica: Procyonidae) population from Panama. Field studies of the coati indicate a social system in which all females are highly philopatric and live in bands while all adult males become solitary at maturity, but do not disperse from the home range of their natal band. Based on analyses of multilocus DNA fingerprints, we confirm that female philopatry is the rule, long‐distance dispersal is rare, and that relatedness between most bands is low. However, some new bands result from fission events and these bands retain relatively high relatedness to one another for several years. Adult males inhabiting the home range of a band are closely related to band members. In contrast, males and band members whose ranges do not overlap are unrelated or only slightly related. Adult males are also more closely related to other males whose home ranges they overlap extensively than to males whose home ranges they overlap only slightly. These results indicate that males initially disperse from their natal bands to reduce resource competition and not to avoid inbreeding. Inbreeding avoidance, if it occurs, results from more extensive range movements by males during the mating season.
Mitochondrial DNA variability in the Canary Islands honeybees (Apis mellifera L.)
Authors: DE LA RÚA P. , SERRANO J. , GALIÁN J.
Published: March 2003

The mitochondrial DNA (mtDNA) of individuals from 79 colonies of Apis mellifera from five Canary Islands was studied using the DraI test based on the restriction of PCR products of the tRNAleu–COII intergenic region. Five haplotypes of the African (A) lineage and one of the west European (C) lineage were found. The haplotypes A14 and A15 are described for the first time. These haplotypes have a new P sequence named P1. The wide distribution and high frequency of haplotype A15 suggest that it is characteristic of the Canarian Archipelago. Sources of haplotype variability of honeybee mtDNA in the Canary Islands (waves of colonization from Africa, queen importations, habitat diversification) are discussed.
Genetic analysis of the population structure of socially organized oystercatchers (Haematopus ostralegus) using microsatellites
Authors: VAN TREUREN R. , BIJLSMA R. , TINBERGEN J. M. , HEG D. , VAN DE ZANDE L.
Published: March 2003

On the island of Schiermonnikoog (The Netherlands), the breeding population of oystercatchers can be divided into two groups: ‘residents’ and ‘leapfrogs’, based on their distinct social characteristics and limited probabilities of status change between breeding seasons. In order to investigate whether this social organization has caused local genetic differentiation, leapfrogs and residents were compared at eight polymorphic microsatellite loci. No significant genetic subdivision between residents and leapfrogs was observed (Θ = 0.0000; 95% confidence interval (CI), –0.0027–0.0033), indicating that the oystercatcher population on the island of Schiermonnikoog has to be considered as one panmictic unit. Investigation of three additional locations in the northern part of The Netherlands did not reveal significant genetic population subdivision either (Θ = – 0.0005; 95% CI, – 0.0045–0.0037), despite the fact that adult oystercatchers show extreme fidelity to their breeding localities. These results indicate panmixis and considerable levels of gene flow within the northern part of The Netherlands. Thus, the results from genetical analyses do not seem to be in agreement with observational data on the dispersal behaviour of breeding individuals. It is argued that the lack of population structure, locally on Schiermonnikoog as well as across larger geographical distances, is to be attributed to high levels of gene flow through dispersal of juvenile birds.
Genetic diversity and microgeographic differentiation of Yushan cane (Yushania niitakayamensis; Poaceae) in Taiwan
Authors: HSIAO J. Y. , LEE S. M.
Published: March 2003

Yushan cane (Yushania niitakayamensis) is distributed in southeast Asia. In Taiwan, the species occurs in mountains 1000–3600 m above sea level. The species appears to spread mainly by rhizomes and flowers only rarely. Nine locations across its distribution range in Taiwan were sampled. Locations at higher altitudes generally consist of grassland and forest undergrowth habitats while those of lower altitudes generally consist of forest undergrowth only. Thus two sampling sites (montane grassland and forest undergrowth) were selected from each location at higher altitudes while only one sampling site was selected from each location at lower altitudes, resulting in a total of 13 sampling sites. Within each sampling site, 20 individual plants were sampled. The results of the cluster analysis and the principal coordinate analysis based on random amplified polymorphic DNA (RAPD) indicated that the populations are generally differentiated according to geographical separation and altitudinal differences that interrupt gene flow. The populations at higher altitudes, where the species is distributed somewhat contiguously, were found to be more similar genetically. Analysis of molecular variance (AMOVA) revealed that the among‐location, between sampling sites within location, and among individuals within sampling site components accounted for 15.27%, 4.80% and 79.93% of the total variance, respectively. For locations with two sampling sites, two‐level AMOVA revealed that the diversities between sampling sites (sun and shade habitats) within locations ranged from 2.91% to 7.99% of the total diversity. Random permutation tests revealed that these diversities were significant, implying that there is microgeographic differentiation due to habitat differences.
The extent of clonality and genetic diversity in the Santa Cruz Island ironwood, Lyonothamnus floribundus
Authors: BUSHAKRA J. M. , HODGES S. A. , COOPER J. B. , KASKA D. D.
Published: March 2003

Lyonothamnus floribundus, or island ironwood, is a relictual endemic species found on only four of the eight California Channel Islands. It has been suggested that this species is capable of clonal growth, although the extent of clonality has not been determined. We have used random amplified polymorphic DNA (RAPD) analysis to examine clonality and genetic diversity in L. floribundus. We found that groves are largely genetically distinct clones, indicating that they are not remnants of a once larger clonal forest. Our data also indicate that the population size of L. floribundus on Santa Cruz Island is closer to 1125 individuals, rather than 32 000 based on the number of trunks. The extensive clonality in this species may have a severe impact on its ability to reproduce sexually owing to limitation of pollinator movements among flowers within a single individual. In addition, our data indicate that the two subspecies of L. floribundus are very closely related rather than being two distinct lineages dating to the Miocene, as indicated by the fossil record.
Microsatellite markers and multiple paternity in the garter snake Thamnophis sirtalis
Authors: Mccracken G. F. , Burghardt G. M. , Houts S. E.
Published: March 2003

Data from four microsatellite loci developed for the common garter snake, Thamnophis sirtalis, show that multiple paternity is common in a natural population on Beaver Island, Michigan. Six of eight litters tested, and all litters with five or more neonates, were multiply sired. At least triple paternity was documented in the largest litter examined (n = 13 neonates). Inheritance patterns and genotype frequencies in the wild population indicate the presence of null allele(s) at one of the microsatellite loci. Garter snakes are widely used in quantitative genetics research, and paternity testing is essential in studies that rely on sibling analysis.
Phylogeographical population structure of tiger quolls Dasyurus maculatus (Dasyuridae: Marsupialia), an endangered carnivorous marsupial
Authors: Firestone K. B. , Elphinstone M. S. , Sherwin W. B. , Houlden B. A.
Published: March 2003

Tiger quolls, Dasyurus maculatus, are the largest carnivorous marsupials still extant on the mainland of Australia, and occupy an important ecological niche as top predators and scavengers. Two allopatric subspecies are recognized, D.m. gracilis in north Queensland, and D.m. maculatus in the southeast of the mainland and Tasmania. D.m. gracilis is considered endangered while D.m. maculatus is listed as vulnerable to extinction; both subspecies are still in decline. Phylogeographical subdivision was examined to determine evolutionarily significant units (ESUs) and management units (MUs) among populations of tiger quolls to assist in the conservation of these taxa. Ninety‐three tiger quolls from nine representative populations were sampled from throughout the species range. Six nuclear microsatellite loci and the mitochondrial DNA (mtDNA) control region (471 bp) were used to examine ESUs and MUs in this species. We demonstrated that Tasmanian tiger quolls are reciprocally monophyletic to those from the mainland using mtDNA analysis, but D.m. gracilis was not monophyletic with respect to mainland D.m. maculatus. Analysis of microsatellite loci also revealed significant differences between the Tasmanian and mainland tiger quolls, and between D.m. gracilis and mainland D.m. maculatus. These results indicate that Tasmanian and mainland tiger quolls form two distinct evolutionary units but that D.m. gracilis and mainland D.m. maculatus are different MUs within the same ESU. The two marker types used in this study revealed different male and female dispersal patterns and indicate that the most appropriate units for short‐term management are local populations. A revised classification and management plan are needed for tiger quolls, particularly in relation to conservation of the Tasmanian and Queensland populations.
Preserving genes, species, or ecosystems? Healing the fractured foundations of conservation policy
Authors: Bowen Brian W.
Published: March 2003

The scientific foundations of conservation policy are the subject of a recent tripolar debate, with systematists arguing for the primacy of phylogenetic rankings, ecologists arguing for protection at the level of populations or ecosystems, and evolutionary biologists urging more attention for the factors that enhance adaptation and biodiversity. In the field of conservation genetics, this controversy is manifested in the diverse viewpoints of molecular systematists, population biologists, and evolutionary (and quantitative) geneticists. A resolution of these viewpoints is proposed here, based on the premise that preserving particularobjects(genes, species, or ecosystems) is not the ultimate goal of conservation. In order to be successful, conservation efforts must preserve theprocessesof life. This task requires the identification and protection of diverse branches in the tree of life (phylogenetics), the maintenance of life‐support systems for organisms (ecology), and the continued adaptation of organisms to changing environments (evolution). None of these objectives alone is sufficient to preserve the threads of life across time. Under this temporal perspective, molecular genetic technologies have applications in all three conservation agendas; DNA sequence comparisons serve the phylogenetic goals, population genetic markers serve the ecological goals, quantitative genetics and genome explorations serve the evolutionary goals.
Molecular genetic analysis among subspecies of two Eurasian sturgeon species, Acipenser baerii and A. stellatus
Authors: Doukakis P. , Birstein V. J. , Ruban G. I. , DeSalle R.
Published: March 2003

Two species, the Siberian sturgeon, Acipenser baerii, and stellate sturgeon, A. stellatus, were studied using mitochondrial DNA (mtDNA) (D‐loop, cytochrome b (cyt‐b) and ND5/6 genes) sequencing to determine whether traditionally defined subspecies correspond to taxonomic entities and conservation management units. Initially, several mtDNA regions for each taxon (A. baerii: 737 bp D‐loop, 750 bp ND5, 200 bp ND6, and 790 bp cyt‐b;A. stellatus: 737 bp D‐loop and 600 bp ND5) were examined. The D‐loop was the most variable region and was sequenced for 35 A. baerii and 82 A. stellatus individuals. No fixed, diagnostic differences were found between any of the subspecies. Geographical structuring of haplotypes was observed within A. baerii, and gene flow estimates suggest isolation of the A. baerii baicalensis subspecies and the Yenisie and Lena River populations. No intraspecific subdivisioning was found within the genetic data for A. stellatus. The use of the phylogenetic criterion (fixed diagnostic differences) for identifying conservation units is compared to the rationale and results of other methods. Overall, morphologically and geographically based subspecies designations within Acipenseridae may not directly correspond to the biological entities appropriate for management and should not be used for conservation programmes without genetic support.
The genetics of amphibian declines: population substructure and molecular differentiation in the Yosemite Toad, Bufo canorus (Anura, Bufonidae) based on single‐strand conformation polymorphism analysis (SSCP) and mitochondrial DNA sequence data
Authors: Shaffer H. Bradley , Fellers Gary M. , Magee Allison , Voss S. Randal
Published: March 2003

We present a comprehensive survey of genetic variation across the range of the narrowly distributed endemic Yosemite toad Bufo canorus, a declining amphibian restricted to the Sierra Nevada of California. Based on 322 bp of mitochondrial cytochrome b sequence data, we found limited support for the monophyly of B. canorus and its closely related congener B. exsul to the exclusion of the widespread western toad B. boreas. However, B. exsul was always phylogenetically nested within B. canorus, suggesting that the latter may not be monophyletic. SSCP (single‐strand conformation polymorphism) analysis of 372 individual B. canorus from 28 localities in Yosemite and Kings Canyon National Parks revealed no shared haplotypes among these two regions and lead us to interpret these two parks as distinct management units for B. canorus. Within Yosemite, we found significant genetic substructure both at the level of major drainages and among breeding ponds. Kings Canyon samples show a different pattern, with substantial variation among breeding sites, but no substructure among drainages. Across the range of B. canorus as well as among Yosemite ponds, we found an isolation‐by‐distance pattern suggestive of a stepping stone model of migration. However, in Kings Canyon we found no hint of such a pattern, suggesting that movement patterns of toads may be quite different in these nearby parklands. Our data imply that management for B. canorus should focus at the individual pond level, and effective management may necessitate reintroductions if local extirpations occur. A brief review of other pond‐breeding anurans suggests that highly structured populations are often the case, and thus that our results for B. canorus may be general for other species of frogs and toads.
Postsealing genetic variation and population structure of two species of fur seal (Arctocephalus gazella and A. tropicalis)
Authors: Wynen Louise P. , Goldsworthy Simon D. , Guinet Christophe , Bester Marthán N. , Boyd Ian L. , Gjertz Ian , Hofmeyr Greg J. G. , White Robert W. G. , Slade Rob
Published: March 2003

Commercial sealing in the 18th and 19th centuries had a major impact on the Antarctic and subantarctic fur seal populations (Arctocephalus gazella and A. tropicalis) in the Southern Ocean. The intensive and unrestricted nature of the industry ensured substantial reductions in population sizes and resulted in both species becoming locally extinct at some sites. However, both species are continuing to recover, through the recolonization of islands across their former range and increasing population size. This study investigated the extent and pattern of genetic variation in each species to examine the hypothesis that higher levels of historic sealing in A. gazella have resulted in a greater loss of genetic variability and population structure compared with A. tropicalis. A 316‐bp section of the mitochondrial control region was sequenced and revealed nucleotide diversities of 3.2% and 4.8% for A. gazella and A. tropicalis, respectively. There was no geographical distribution of lineages observed within either species, although the respective ΦST values of 0.074 and 0.19 were significantly greater than zero. These data indicate low levels of population structure in A. gazella and relatively high levels in A. tropicalis. Additional samples screened with restriction endonucleases were incorporated, and the distribution of restriction fragment length polymorphism (RFLP) and sequence haplotypes were examined to identify the main source populations of newly recolonized islands. For A. tropicalis, the data suggest that Macquarie Island and Iles Crozet were probably recolonized by females from Marion Island, and to a lesser extent Ile Amsterdam. Although there was less population structure within A. gazella, there were two geographical regions identified: a western region containing the populations of South Georgia and Bouvetøya, which were the probable sources for populations at Marion, the South Shetland and Heard Islands; and an eastern region containing the panmictic populations of Iles Kerguelen and Macquarie Island. The latter region may be a result of a pronounced founder effect, or represent a remnant population that survived sealing at Iles Kerguelen.
Postglacial recolonization routes for Picea abies K. in Italy as suggested by the analysis of sequence‐characterized amplified region (SCAR) markers
Authors: Scotti I. , Vendramin G. G. , Matteotti L. S. , Scarponi C. , Sari‐Gorla M. , Binelli G.
Published: March 2003

The routes through which Norway spruce recolonized the Alps after the last ice age were investigated at the genetic level. Seven populations along the Alpine range plus one Apennine population were characterized for seven sequence‐characterized amplified region (SCAR) loci, detecting an overall FST = 0.118. This rather high value for forest species reflects an uneven distribution of genetic variability, and was analysed through different statistical methods. Alternative hypotheses were tested under the isolation‐by‐distance model and using the analysis of molecular variance (
amova) frame. We conclude that the hypothesis of the existence of a glacial refugium in the Apennines should be rejected, while a putative relict population is identified in the Maritime Alps. The Alpine range of Norway spruce appears to be split in two parts across a north–south line. The results are discussed in comparison with data based on morphological markers, isozymes, chloroplast microsatellites and mitochondrial markers.
Matrilineal history of the endangered Cape Sable seaside sparrow inferred from mitochondrial DNA polymorphism
Authors: Nelson William S. , Dean Tylan , Avise John C.
Published: March 2003

Restriction analyses were conducted on mitochondrial DNA (mtDNA) amplified by long‐PCR from an endangered bird, the Cape Sable seaside sparrow. The first of several successful mtDNA amplifications was accomplished using the partially digested tissue remains of a transmitter‐monitored bird retrieved from the gut of a snake. As many as 91 mtDNA restriction fragments produced by 18 endonucleases were compared in this and four other Cape Sable specimens against mtDNA similarly amplified by long‐PCR from other taxonomic forms in the seaside sparrow complex. Results indicate that the Cape Sable birds belong to an ‘Atlantic’ matrilineal clade, and are highly divergent from other seaside sparrows along the Gulf of Mexico.
Genetic variation and structure in sixRhododendronspecies (Ericaceae) with contrasting local distribution patterns in Hong Kong, China
Authors: Ng Sai‐Chit , Corlett Richard T.
Published: March 2003

Genetic variability of six rhododendrons with contrasting local distribution patterns in Hong Kong was assessed by starch gel electrophoresis.Rhododendron championiae,R. hongkongenseandR. simiarumare locally rare with disjunct distributions,R. moulmainenseis restricted andR. farreraeandR. simsiiare common. For each species, 13–18 allozyme loci representing 12–16 enzyme systems were scored. The six species showed similar levels of genetic variations (HTranged from 0.209 to 0.386 andATranged from 2.4 to 4.1) which are high compared to plants with similar life history traits. Genetic structure, in contrast, varied greatly between species, withFSTranging from 0.056 to 0.393. The three rarest species had high genetic differentiation (FSTandFPT) and distinct geographical patterns, while the other three had low differentiation and little or no geographical structure. These differences are attributed to both present distributions and historical changes following deforestation within the last 1000 years. The conservation implications of these results are discussed.
Comparative avian phylogeography of Cameroon and Equatorial Guinea mountains: implications for conservation
Authors: Smith T. B. , Holder K. , Girman D. , O’Keefe K. , Larison B. , Chan Y.
Published: March 2003

We illustrate the use of Faith’s ‘Phylogenetic Diversity’ measure to compare the phylogeographic structure of two bird species with patterns of avian endemism across six mountains in Cameroon and Equatorial Guinea. The Mountain Greenbul and Cameroon Blue‐headed Sunbird showed phylogeographic patterns that together defined three biogeographic regions: Bioko, Mt. Cameroon, and the northern mountains of Cameroon. In contrast, the distributions of endemic species were largely a function of geographical distance, with close mountains sharing more endemic species than distant mountains. Moreover, for both species, populations on Mt. Cameroon were distinctive with respect to the ecologically relevant character bill size. Our results, while preliminary, illustrate the utility of a comparative approach for identifying geographical regions that harbour evolutionarily distinct populations and caution against using only the distributional patterns of endemics to prioritize regions for conservation. Results show that patterns of endemism may not be concordant with patterns of phylogenetic diversity nor morphological variation in a character important in fitness. While incorporation of additional species from unrelated taxa will be necessary to draw definitive conclusions about evolutionarily distinct regions, our preliminary results suggest a conservation approach for the Afromontane region of the Gulf of Guinea that would: (i) emphasize protection of both Bioko and Mt. Cameroon, thereby maximizing preservation of within–species phylogenetic and morphologic diversity; (ii) emphasize protection within the northern mountains to further conserve intraspecific phylogenetic diversity and maximize protection of endemic species.
Genetic evidence for a family structure in stable social aggregations of the Australian lizard Egernia stokesii
Authors: Gardner M. G. , Bull C. M. , Cooper S. J. B. , Duffield G. A.
Published: March 2003

In this study we used data from six unlinked microsatellite loci to examine stable aggregations of Egernia stokesii, from a population in the southern Flinders Ranges of South Australia. We show that these aggregations are comprised of breeding partners, their offspring from two or more cohorts, and related adults, providing the first genetic evidence of a family structure in any lizard species. Despite this high level of relatedness within aggregations, most breeding pairs were unrelated and partners were less closely related to each other than they were to other potential within‐group partners. Where individuals dispersed, both sexes usually moved to social groups close to their natal group. Although both sexes showed natal philopatry, there was some evidence that females in groups were more related than males in groups. These data suggest that an active choice of unrelated partners and male‐biased dispersal may be the mechanisms used by E. stokesii to avoid inbreeding within groups.
Mitochondrial DNA, ecology and morphology: interpreting the phylogeography of the Nesotes (Coleoptera: Tenebrionidae) of Gran Canaria (Canary Islands)
Authors: Rees D. J. , Emerson B. C. , Oromí P. , Hewitt G. M.
Published: March 2003

The genus Nesotes (Coleoptera: Tenebrionidae) is represented in the Canary Islands by 19 endemic species, the majority of which are single island endemics. Nesotes conformis and N. fusculus are described on four and three islands, respectively, but each forms a paraphyletic assemblage between Gran Canaria and the other islands. The other described species for Gran Canaria are N. quadratus, N. lindbergi and N. piliger. Thirty‐six individuals representing the five species on Gran Canaria have been sequenced for 675 bp of the mitochondrial DNA (mtDNA) cytochrome oxidase II gene. Neighbour‐joining analysis of maximum likelihood distances resulted in five distinct mtDNA lineages for N. quadratus, two of which also include mitotypes of N. conformis. Each of the other three species is found on only one mtDNA lineage. We propose from the molecular data that differentiation in a widespread N. quadratus‐type ancestor was followed by morphological adaptation to coastal, pine and laurel forest habitats.
Haplotype variation in a mitochondrial tandem repeat of Norway spruce (Picea abies) populations suggests a serious founder effect during postglacial re‐colonization of the western Alps
Authors: Gugerli Felix , Sperisen Christoph , Büchler Urs , Magni Federica , Geburek Thomas , Jeandroz Sylvain , Senn Josef
Published: March 2003

Populations from 13 elevational transects of Norway spruce [Picea abies (L.) Karst] across the Alpine range were sampled to elucidate the geographical pattern of genetic variation in relation to postglacial re‐colonization and to study elevational effects on haplotypic diversity. We assessed fragment length variation in a tandem repeat region of the mitochondrial (mt) nad1 intron 2. This maternally inherited genetic marker is suited to infer migration as it is dispersed by seed only. A total of 10 haplotypes was found, most of which were due to repeat copy number variation. An analysis of molecular variance (amova) showed that overall population differentiation was high (FST = 0.41), and it revealed a significant differentiation between monomorphic western and moderately to highly variable eastern Alpine populations. This phylogeographic pattern may be explained by a founder effect during postglacial re‐colonization. An early arriving haplotype, assumed to originate from a western Carpathian refugium, could expand into suitable habitats, reducing the chances for establishment of subsequently arriving haplotypes. On the other hand, the high variation in populations within an Italian transect of the south‐eastern Alps may be the consequence of merging migration pathways from and close distance to putative glacial refugia, most likely those assumed in the Carpathian mountains and on the Balkan peninsula or possibly in the central plains of Italy. An effect of elevation on haplotypic diversity was not evident, though a low, but significant, partition of total genetic variation was attributed to among‐population variation in one Italian transect. Various factors, such as vertical seed dispersal and forest management, may account for blurring an otherwise established pattern of genetic variation on a small geographical scale.
Resolution of natural groups using iterative assignment tests: an example from two species of Australian native rats (Rattus)
Authors: VÁzquez‐Domínguez E. , Paetkau D. , Tucker N. , Hinten G. , Moritz C.
Published: March 2003

Sympatric individuals of Rattus fuscipes and Rattus leucopus, two Australian native rats from the tropical wet forests of north Queensland, are difficult to distinguish morphologically and are often confused in the field. When we started a study on fine‐scale movements of these species, using microsatellite markers, we found that the species as identified in the field did not form coherent genetic groups. In this study, we examined the potential of an iterative process of genetic assignment to separate specimens from distinct (e.g. species, populations) natural groups. Five loci with extensive overlap in allele distributions between species were used for the iterative process. Samples were randomly distributed into two starting groups of equal size and then subjected to the test. At each iteration, misassigned samples switched groups, and the output groups from a given round of assignment formed the input groups for the next round. All samples were assigned correctly on the 10th iteration, in which two genetic groups were clearly separated. Mitochondrial DNA sequences were obtained from samples from each genetic group identified by assignment, together with those of museum voucher specimens, to assess which species corresponded to which genetic group. The iterative procedure was also used to resolve groups within species, adequately separating the genetically identified R. leucopus from our two sampling sites. These results show that the iterative assignment process can correctly differentiate samples into their appropriate natural groups when diagnostic genetic markers are not available, which allowed us to resolve accurately the two R. leucopus and R. fuscipes species. Our approach provides an analytical tool that may be applicable to a broad variety of situations where genetic groups need to be resolved.
Idengification of the origin of an Atlantic salmon (Salmo salar L.) population in a recently recolonized river in the Baltic Sea
Authors: Vasemägi A. , Gross R. , Paaver T. , Kangur M. , Nilsson J. , Eriksson L.‐O.
Published: March 2003

The founder event in a recently recolonized salmon population in the Baltic Sea (Gulf of Finland) was investigated. To idengify the origin of the founders, four wild populations and two hatchery stocks were analysed using six microsatellite loci. The results of assignment tests and factorial correspondence analysis suggest that the initial recolonizers of the river Selja originated from the geographically nearest (7 km) wild population (river Kunda) but as the result of stocking activities, interbreeding between recolonizers and hatchery individuals has occurred in subsequent years. Although the hatchery releases are outnumbering the wild salmon recruitment in the Baltic Sea at present, our results suggest that the native populations may still have an important role in colonization processes of the former salmon rivers.
Evidence of low gene flow in a neotropical clustered tree species in two rainforest stands of French Guiana
Authors: Dutech C. , Seiter J. , Petronelli P. , Joly H. I. , Jarne P.
Published: March 2003

The spatial genetic structure of the neotropical, clustered tree speciesVouacapoua americana(Aublet) was studied in two natural forest stands (Paracou and Nouragues) in French Guiana. Using eight microsatellite loci,V. americanais characterized by a marked genetic structure at small spatial distances (under 30–60 m), in agreement with the limited seed dispersal by rodent species. Gene flow through pollen is also shown to be mainly restricted to less than 100 m. This result suggests that most pollination events (mediated through small insects) are probably limited to within‐patches of individuals, which might explain the high genetic differentiation among patches (FST = 0.11) separated by less than 2 km. We also assume that stronger genetic structure in Paracou is likely to be due to lower seed dispersal by rodents, large spatial distances separating patches, or a recent recolonization event.
The genetic structure of the rare lagoonal sea anemone,Nematostella vectensisStephenson (Cnidaria; Anthozoa) in the United Kingdom based on RAPD analysis
Authors: Pearson C. V. M. , Rogers A. D. , Sheader M.
Published: March 2003

The sea anemoneNematostella vectensisoccurs in lagoons in the United States and along the southern and eastern coasts of the United Kingdom. In the United Kingdom it is considered rare and is threatened, principally through the destruction of lagoonal habitat. Random amplified polymorphic DNA (RAPD) data from populations across most of the rane ofN. vectensisin the United Kingdom revealed that 61% of individuals had an identical genotype, the frequency of which varied from 0.01 to 1.00. These data provide strong evidence for predominantly clonal reproduction and for the existence of a ‘general‐purpose genotype’ in the UK populations. Alternatively, the low levels of genetic variation observed in someN. vectensispopulations may have resulted if they were founded from very few successful individuals from the United States. Analysis of molecular variance (amova) showed significant genetic differentiation between lagoons with no large‐scale pattern of geographical variation. This result is consistent with occasional passive or anthropogenic dispersal of low numbers of individuals between lagoons followed by asexual proliferation of immigrants. Transplantation of individuals of the predominant (general‐purpose) genotype, for conservation purposes, will probably stand a good chance of survival given its prevalence throughout the United Kingdom.
Nestmate relatedness and population genetic structure of the Australian social crab spiderDiaea ergandros(Araneae: Thomisidae)
Authors: Evans Theodore A. , Goodisman Michael A. D.
Published: March 2003

We characterized the population genetic structure of the Australian social spiderDiaea ergandrosusing polymorphic allozyme markers. Our main objectives were to understand the social organization ofD. ergandrosand discern patterns of gene flow across distantly separated geographical areas. Spiders were sampled from nests located within 100 m wide locales, which were distributed within larger 50 km wide regions. Our results indicated that nestmates could have been produced by a single mother and father in 88.9% ofD. ergandrosnests. The remainder of nests contained spiders that were probably produced by polyandrous females or were immigrants from foreign nests. Nestmate relatedness was relatively high (r = 0.44) and did not differ significantly between the sexes or among juvenile, subadult and adult life stages. We also discovered thatD. ergandrospopulations were highly structured, with significant differentiation detected among locales (FLR = 0.23) and regions (FRT = 0.081). Spiders within locales were also substantially inbred (FIL = 0.15). Overall, our data show that significant population subdivision exists inD. ergandrospopulations, and we suggest that the poor dispersal ability ofDiaeaspiders can account for the observed genetic structure.
Population genetics of wolf spiders of fragmented habitat in the wheat belt of New South Wales
Authors: Colgan D. J. , Brown S. , Major R. E. , Christie F. , Gray M. R. , Cassis G.
Published: March 2003

Possible effects of habitat fragmentation on the population genetics of a species of wolf spider (Lycosidae) from remnantCallitriswoodland in the wheat belt of central western New South Wales in Australia are examined. Single‐strand conformational analysis of mitochondrial cytochrome oxidase (subunit 1) was used to characterize the haplotypes of 295 spiders in six blocks each of four woodland sites. DNA sequences were collected from 119 of these spiders to confirm haplotype scoring, allow phylogeny estimation and permit calculation of sequence‐based statistics. Intra‐block tests do not suggest widespread effects of fragmentation. Genetic diversity is high in all blocks, with 25 haplotypes being identified. Nucleotide diversity is relatively low, as all of the haplotypes are closely related. One block had a significantly low value for the Ewens/Watterson test of neutrality and one block's value was nearly significantly high. Two blocks had nearly significant values of the Harpending Raggedness Index testing for recent population bottlenecks. No other intrablock tests approach significance. Interpopulation comparisons show significant nonhomogeneity of haplotype frequencies globally and in all pairwise comparisons. Relationships between woodland blocks based on haplotype frequencies are discordant with geographical proximity. Haplotype distribution patterns suggest that population structuring existed prior to fragmentation. We develop two measures of genetic distinctiveness to identify subpopulations of interest for conserving evolutionary processes in a species’ regional population. One is based on the sum of pairwiseFSTvalues and one on the spatial distribution of genetic variation. High values of the measure suggest a subpopulation might have been recently perturbed and low values that it is relatively undisturbed. The two measures identify different blocks as being of particular interest.
Polymerase chain reaction–single strand conformation polymorphism analyses of nuclear and chloroplast DNA provide evidence for recombination, multiple introductions and nascent speciation in the Caulerpa taxifolia complex
Authors: Meusnier I. , Valero M. , Destombe C. , Godé C. , Desmarais E. , Bonhomme F. , Stam W. T. , Olsen J. L.
Published: March 2003

Independent lines of evidence support an Australian origin for the Mediterranean populations of the tropical alga Caulerpa taxifolia. To complement previous biogeographical studies based on nuclear rDNA internal transcribed spacer (ITS), a new chloroplast marker was developed — the cp 16S rDNA intron‐2. Sequence variability for both nuclear and chloroplast markers were assessed in 110 individuals using single strand conformation polymorphism. Comparison of intrapopulation genetic diversity between invasive Mediterranean and ‘native’ Australian populations revealed the occurrence of two divergent and widespread clades. The first clade grouped nontropical invasive populations with inshore‐mainland populations from Australia, while the second clustered all offshore‐island populations studied so far. Despite our finding of nine distinct nuclear and five distinct chloroplast profiles, a single nucleocytoplasmic combination was characteristic of the invasive populations and sexual reproduction was found to be very rare. C. taxifolia is clearly a complex of genetically and ecologically differentiated sibling species or subspecies.