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Ricardo L. Palma

Bio: Ricardo L. Palma is an academic researcher from Museum of New Zealand Te Papa Tongarewa. The author has contributed to research in topics: Philopteridae & Menoponidae. The author has an hindex of 21, co-authored 115 publications receiving 2371 citations. Previous affiliations of Ricardo L. Palma include Wellington Management Company & University of Glasgow.
Topics: Philopteridae, Menoponidae, Louse, Genus, Ischnocera


Papers
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Journal ArticleDOI
TL;DR: The author has had the unfortunate experience of having to examine type specimens mounted in polyvinyl alcohol which showed marked signs of deterioration after only 15 years, and has led the author to publish the basic Canada balsam technique in the hope that it will facilitate good standardised results by workers in this field.
Abstract: (1978). Slide-mounting of Lice: a Detailed Description of the Canada Balsam technique. New Zealand Entomologist: Vol. 6, No. 4, pp. 432-436.

200 citations

Journal ArticleDOI
TL;DR: Perfect congruence between phylogenies is not found in this association, probably as a result of occasional host switching by the lice, thus emphasizing the need for improved cophylogenetic methodologies.
Abstract: Lice in the genus Pectinopygus parasitize a single order of birds (Pelecaniformes). To examine the degree of congruence between the phylogenies of 17 Pectinopygus species and their pelecaniform hosts, sequences from mitochondrial 12S rRNA, 16S rRNA, COI, and nuclear wingless and EF1-alpha genes (2290 nucleotides) and from mitochondrial 12S rRNA, COI, and ATPases 8 and 6 genes (1755 nucleotides) were obtained for the lice and the birds, respectively. Louse data partitions were analyzed for evidence of incongruence and evidence of long-branch attraction prior to cophylogenetic analyses. Host-parasite coevolution was studied by different methods: TreeFitter, TreeMap, ParaFit, likelihood-ratio test, data-based parsimony method, and correlation of coalescence times. All methods agree that there has been extensive cospeciation in this host-parasite system, but the results are sensitive to the selection of different phylogenetic hypotheses and analytical methods for evaluating cospeciation. Perfect congruence between phylogenies is not found in this association, probably as a result of occasional host switching by the lice. Errors due to phylogenetic reconstruction methods, incorrect or incomplete taxon sampling, or to different loci undergoing different evolutionary histories cannot be rejected, thus emphasizing the need for improved cophylogenetic methodologies.

103 citations


Cited by
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TL;DR: Given the complexity of processes that underlie biological invasions, it is argued against a simple relationship between enemy ‘release’ and the vigour, abundance or impact of NIS.
Abstract: A recent trend in invasion ecology relates the success of non-indigenous species (NIS) to reduced control by enemies such as pathogens, parasites and predators (i.e. the enemy release hypothesis, ERH). Despite the demonstrated importance of enemies to host population dynamics, studies of the ERH are split – biogeographical analyses primarily show a reduction in the diversity of enemies in the introduced range compared with the native range, while community studies imply that NIS are no less affected by enemies than native species in the invaded community. A broad review of the invasion literature implies at least eight non-exclusive explanations for this enigma. In addition, we argue that the ERH has often been accepted uncritically wherever (i) NIS often appear larger, more fecund, or somehow ‘better’ than either congeners in the introduced region, or conspecifics in the native range; and (ii) known enemies are conspicuously absent from the introduced range. However, all NIS, regardless of their abundance or impact, will lose natural enemies at a biogeographical scale. Given the complexity of processes that underlie biological invasions, we argue against a simple relationship between enemy ‘release’ and the vigour, abundance or impact of NIS.

1,198 citations

Journal ArticleDOI
04 Jan 2013-Science
TL;DR: A global map of zoogeographic regions is generated by combining data on the distributions and phylogenetic relationships of 21,037 species of amphibians, birds, and mammals, and it is shown that spatial turnover in the phylogenetic composition of vertebrate assemblages is higher in the Southern than in the Northern Hemisphere.
Abstract: Modern attempts to produce biogeographic maps focus on the distribution of species, and the maps are typically drawn without phylogenetic considerations. Here, we generate a global map of zoogeographic regions by combining data on the distributions and phylogenetic relationships of 21,037 species of amphibians, birds, and mammals. We identify 20 distinct zoogeographic regions, which are grouped into 11 larger realms. We document the lack of support for several regions previously defined based on distributional data and show that spatial turnover in the phylogenetic composition of vertebrate assemblages is higher in the Southern than in the Northern Hemisphere. We further show that the integration of phylogenetic information provides valuable insight on historical relationships among regions, permitting the identification of evolutionarily unique regions of the world.

1,014 citations

01 Nov 2011
TL;DR: The Communication program emphasizes theory, research, and application to examine the ways humans communicate, verbally and non-verbally, across a variety of levels and contexts, to understand ourselves, the authors' media, their relationships, their culture and how these things connect.
Abstract: The Communication program emphasizes theory, research, and application to examine the ways humans communicate, verbally and non-verbally, across a variety of levels and contexts. This is particularly important as communication shapes our ideas and values, gives rise to our politics, consumption and socialization, and helps to define our identities and realities. Its power and potential is inestimable. From the briefest of text messages to the grandest of public declarations, we indeed live within communication and invite you to join us in appreciating its increasing importance in contemporary society. From Twitter and reality television to family relationships and workplace dynamics, communication is about understanding ourselves, our media, our relationships, our culture and how these things connect.

822 citations

Journal ArticleDOI
TL;DR: The emphasis for future research must shift from pattern description to the elucidation of the processes responsible for the structure and diversity of parasite faunas, and a better integration of ecological and historical approaches to the study of parasite diversity should make this objective possible.
Abstract: Parasitism is one of the most successful modes of life displayed by living organisms, as measured by how often it evolved and how many parasitic species are presently in existence. Studying the diversity of parasites is particularly relevant because sympatric diversification may be important in some parasite taxa, and because of the opportunity for independent tests of evolutionary hypotheses in the many separate lineages in which parasitism evolved. Our incomplete knowledge of existing parasite species--the result of a range of phenomena that includes inadequate sampling effort or the lumping of different cryptic species under one name--is not always a major obstacle for the study of parasite diversity. Patterns in the diversity of parasites may be associated with either host or parasite characteristics. The distribution of parasite diversity among host taxa does not simply reflect the species diversity of the host taxa themselves; life history and ecological traits of hosts appear to play important roles. These may determine the likelihood that hosts are colonized by parasite species over evolutionary time. It is not yet clear whether some host traits also favor intrahost speciation and diversification of parasites, and the formation of new parasite species. Certain features of parasites may also be associated with speciation and diversification. Only parasite body size has received much attention; the patterns observed are not greatly different from those of free-living species, with small-bodied parasite taxa being more speciose than related large-bodied taxa. Epidemiological parameters such as the basic reproductive rate of parasites, or R0, can also generate predictions regarding the distribution or evolution of parasite diversity. For instance, parasite taxa characterized by high R0 values may be more speciose than related taxa with lower values of R0; such predictions remain untested. Large-scale biogeographical patterns of diversity have only been well studied for metazoan parasites of marine fish; for these parasites, latitudinal patterns can be explained by effects of temperature on speciation rates and epidemiological variables, though other causes are possible. The emphasis for future research must shift from pattern description to the elucidation of the processes responsible for the structure and diversity of parasite faunas. A better integration of ecological and historical (or phylogenetic) approaches to the study of parasite diversity should make this objective possible.

565 citations

Journal ArticleDOI
TL;DR: A phylogenetic (cladistic) analysis of 150 taxa of Neornithes, including exemplars from all non-passeriform families, and subordinal representatives of Passeriformes, confirmed the topology among outgroup Theropoda and achieved robust resolution at virtually all levels of the NeornIthes.

506 citations