Immunology and Infectious Disease Commons^™

Worldwide Host Associations Of The Tick Genus Ixodes Suggest Relationships Based On Environmental Sharing Rather Than On Co-Phylogenetic Events, Agustín Estrada-Peña, Alberto A. Guglielmone, Santiago Nava

Harold W. Manter Laboratory: Library Materials

Abstract

Background

This study aims to capture how ticks of the genus Ixodes gained their hosts using network constructs. We propose two alternative hypotheses, namely, an ecological background (ticks and hosts sharing environmentally available conditions) and a phylogenetic one, in which both partners co-evolved, adapting to existing environmental conditions after the association took place.

Methods

We used network constructs linking all the known pairs of associations between each species and stage of ticks with families and orders of hosts. Faith’s phylogenetic diversity was used to evaluate the phylogenetic distance of the hosts of each species and changes occurring in the …

Circling The Drain: The Extinction Crisis And The Future Of Humanity, Rodolfo Dirzo, Gerardo Ceballos, Paul R. Ehrlich

Harold W. Manter Laboratory: Library Materials

Humanity has triggered the sixth mass extinction episode since the beginning of the Phanerozoic. The complexity of this extinction crisis is centered on the intersection of two complex adaptive systems: human culture and ecosystem functioning, although the significance of this intersection is not properly appreciated. Human beings are part of biodiversity and elements in a global ecosystem. Civilization, and perhaps even the fate of our species, is utterly dependent on that ecosystem’s proper functioning, which society is increasingly degrading. The crisis seems rooted in three factors. First, relatively few people globally are aware of its existence. Second, most people who …

Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction, Gerardo Ceballos, Paul R. Ehrlich, Peter H. Raven

Harold W. Manter Laboratory: Library Materials

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in …

Novel Information On The Morphology, Phylogeny And Distribution Of Camallanid Mematodes From Marine And Freshwater Hosts In South Africa, Including The Description Of Camallanus Sodwanaensis N. Sp., Roman Svitin, Marliese Truter, Olena Kudlai, Nico J. Smit, Louis Du Preez

Harold W. Manter Laboratory: Library Materials

Four species of previously known nematodes from the family Camallanidae were found from different hosts in South Africa: Batrachocamallanus xenopodis from the frog Xenopus muelleri, Paracamallanus cyathopharynx, and Procamallanus pseudolaeviconchus from the catfish Clarias gariepinus and Spirocamallanus daleneae from the catfish Synodontis zambezensis. In the material collected from various marine fishes, several specimens of nematodes from the genus Camallanus clearly differed from all previously known species. Based on morphological differences these specimens are assigned to a new species, C. sodwanaensis. Molecular data of 18S and 28S rDNA and COI sequences are provided for the collected species …

Some Aspects Of The Biology Of Monogenean (Platyhelminth) Parasites Of Marine And Freshwater Fishes, Graham C. Kearn

Harold W. Manter Laboratory: Library Materials

Müller was the first to describe a monogenean, collected from the skin of the halibut (Hippoglossus hippoglossus). However, he regarded the parasite as a leech and named it Hirudo hippoglossi. It was not until 1858 that its status as a monogenean was established by van Beneden and named Epibdella (now Entobdella) hippoglossi. Van Beneden published a detailed and accurate description of the parasite and one of his excellent illustrations is reproduced here. Entobdella hippoglossi is one of the largest monogeneans, measuring up to 2 cm in length. It has a smaller relative, measuring 5 to …

Evolutionary History Of Assassin Bugs (Insecta: Hemiptera: Reduviidae): Insights From Divergence Dating And Ancestral State Reconstruction, Wei Song Hwang, Christiane Weirauch

Harold W. Manter Laboratory: Library Materials

Assassin bugs are one of the most successful clades of predatory animals based on their species numbers (~ 6,800 spp.) and wide distribution in terrestrial ecosystems. Various novel prey capture strategies and remarkable prey specializations contribute to their appeal as a model to study evolutionary pathways involved in predation. Here, we reconstruct the most comprehensive reduviid phylogeny (178 taxa, 18 subfamilies) to date based on molecular data (5 markers). This phylogeny tests current hypotheses on reduviid relationships emphasizing the polyphyletic Reduviinae and the blood-feeding, diseasevectoring Triatominae, and allows us, for the first time in assassin bugs, to reconstruct ancestral states …

How Birds Combat Ectoparasites, Dale H. Clayton, Jennifer A. H. Koop, Christopher W. Harbison, Brett R. Moyer, Sarah E. Bush

Harold W. Manter Laboratory: Library Materials

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 significance 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 …