Evolutionary Parasitology

Author(s):  
Paul Schmid-Hempel

Parasites are ubiquitous and shape almost every aspect of their hosts, including physiology, behaviour, life histories, the structure of the microbiota, and entire communities. Hence, parasitism is one of the most potent forces in nature and, without parasites, the world would look very different. The book gives an overview over the parasite groups and the diversity of defences that hosts have evolved, such as immune systems. Principles of evolutionary biology and ecology analyse major elements of host–parasite interactions, including virulence, infection processes, tolerance, resistance, specificity, memory, polymorphisms, within-host dynamics, diseases spaces, and many other aspects. Genetics is always one of the key elements in these topics. Modelling, furthermore, can predict best strategies for host and parasites. Similarly, the spread of an infectious disease in epidemiology combines with molecular data and genomics. Furthermore, parasites have evolved ways to overcome defences and to manipulate their hosts. Hosts and parasites, therefore, continuously co-evolve, with changes sometimes occurring very rapidly, and sometimes requiring geological times. Many infectious diseases of humans have emerged from a zoonotic origin, in processes governed by the basic principles discussed in the different sections. Hence, this book integrates different fields to study the diversity of host–parasite processes and phenomena. It summarizes the essential topics for the study of evolutionary parasitology and will be useful for a broad audience.

Crustaceana ◽  
2016 ◽  
Vol 89 (11-12) ◽  
pp. 1243-1446 ◽  
Author(s):  
Lourelle A. M. Neethling ◽  
Annemariè Avenant-Oldewage

This is a compendium of current knowledge about the crustacean subclass Branchiura Thorell, 1864. An overview of the group is presented, starting from the first species description, and reports of taxonomic changes. It also provides a condensed retrospect of each genus and includes the characteristics of each genus, the geographical distribution of each species arranged according to occurrence per continent; and aspects of the anatomy, physiology, host-parasite interactions and phylogeny are discussed. In order to condense the information available on members of the subclass, additional literature sources on each aspect are tabulated. The species lists provided by the World Register of Marine Species (WoRMS) were used as a starting point as these were the most comprehensive currently available.


2011 ◽  
Vol 51 ◽  
pp. 161-175 ◽  
Author(s):  
Christopher M. Ryan ◽  
Natalia de Miguel ◽  
Patricia J. Johnson

Trichomonas vaginalis is a sexually transmitted obligate extracellular parasite that colonizes the human urogenital tract. Despite being of critical importance to the parasite's survival relatively little is known about the mechanisms employed by T. vaginalis to establish an infection and thrive within its host. Several studies have focused on the interaction of the parasite with host cells and extracellular matrix, identifying multiple suspected T. vaginalis adhesins. However, with the exception of its surface lipophosphoglycan, the evidence supporting a role in adhesion is indirect or controversial for many candidate molecules. The availability of the T. vaginalis genome sequence paved the way for genomic analyses to search for proteins possibly involved in host–parasite interactions. Several proteomic analyses have also provided insight into surface, soluble and secreted proteins that may be involved in Trichomonas pathogenesis. Although the accumulation of molecular data allows for a more rational approach towards identifying drug targets and vaccine candidates for this medically important parasite, a continued effort is required to advance our understanding of its biology. In the present chapter, we review the current status of research aimed at understanding T. vaginalis pathogenesis. Applied experimental approaches, an overview of significant conclusions drawn from this research and future challenges are discussed.


Author(s):  
Michael Ruse

In recent years, philosophers have come to realize that the relationship between science and values raises questions which are both important and not readily answered. It is true that the major figures in that tradition known as ‘logical empiricism’ appreciated that science always exceeds its empirical grasp and that it is necessary for scientists to be guided and constrained by so-called ‘epistemic values,’ these being values (in the words of one supporter) ‘presumed to promote the truth-like character of science, its character as the most secure knowledge available to us of the world we seek to understand.’ However, these values — such things as internal and external consistency, simplicity, predictive accuracy and fertility, unificatory power (consilience) — were considered special. Inasmuch as they could not be reduced to basic principles of logic — and there were attempts to do this — they were still thought of, in some sense, as beyond the vagaries of human emotion. Their importance was not a function of the individual’s personal inclinations, nor of those of the group, whether this group be understood as a closely knit band of researchers or even up to a complete society.


Parasitology ◽  
2013 ◽  
Vol 141 (4) ◽  
pp. 462-474 ◽  
Author(s):  
ALEXANDRE BUDRIA ◽  
ULRIKA CANDOLIN

SUMMARYHost-parasite interactions are an integral part of ecosystems that influence both ecological and evolutionary processes. Humans are currently altering environments the world over, often with drastic consequences for host-parasite interactions and the prevalence of parasites. The mechanisms behind the changes are, however, poorly known. Here, we explain how host-parasite interactions depend on two crucial steps – encounter rate and host-parasite compatibility – and how human activities are altering them and thereby host-parasite interactions. By drawing on examples from the literature, we show that changes in the two steps depend on the influence of human activities on a range of factors, such as the density and diversity of hosts and parasites, the search strategy of the parasite, and the avoidance strategy of the host. Thus, to unravel the mechanisms behind human-induced changes in host-parasite interactions, we have to consider the characteristics of all three parts of the interaction: the host, the parasite and the environment. More attention should now be directed to unfold these mechanisms, focusing on effects of environmental change on the factors that determine encounter rate and compatibility. We end with identifying several areas in urgent need of more investigations.


2021 ◽  
Vol 95 ◽  
Author(s):  
Yuri Willkens ◽  
Adriano Penha Furtado ◽  
Jeannie Nascimento dos Santos ◽  
Francisco Tiago de Vasconcelos Melo

Abstract The genus Oswaldocruzia Travassos, 1917 includes approximately 90 species that are parasitic on amphibians and reptiles around the world, of which 43 occur in the neotropical region. However, molecular data supporting the taxonomic status of most species of the genus are scarce, and their phylogenetic relationships remain unknown. Using specimens of four molineid taxa (Oswaldocruzia belenensis Santos, Giese, Maldonado Jr. and Lanfredi, 2008; Oswaldocruzia chabaudi Ben Slimane & Durette-Desset, 1996, Oswaldocruzia chambrieri Ben Slimane & Durette-Desset, 1996 and Kentropyxia hylae Feitosa, Furtado, Santos and Melo, 2015) from amphibian hosts collected in different regions of Pará, Brazil, we conducted morphological studies, molecular analyses and phylogenies (maximum likelihood and Bayesian inference) using the cytochrome c oxidase subunity I (Cox1) gene. The newly generated sequences were compared with those of ten publicly available Cox1 sequences of Oswaldocruzia from Mexico. Our findings demonstrated significant differences between the sequences of amazonian specimens and sequences from specimens collected in Mexico, and we suggest that host–parasite cospeciation or habitat use might be related to molineid evolution in amphibian hosts. Additionally, this work presents new hosts and new geographical records for species of Oswaldocruzia from the neotropics.


Author(s):  
Pauline Ezanno ◽  
Elisabeta Vergu ◽  
Michel Langlais ◽  
Emmanuelle Gilot-Fromont

Think India ◽  
2019 ◽  
Vol 22 (2) ◽  
pp. 463-466
Author(s):  
TUMMALA. SAI MAMATA

A river flows serenely accepting all the miseries and happiness that it comes across its journey. A tree releases oxygen for human beings despite its inner plights. The sun is never tired of its duty and gives sunlight without any interruption. Why are all these elements of nature so tuned to? Education is knowledge. Knowledge comes from learning. Learning happens through experience. Familiarity is the master of life that shapes the individual. Every individual learns from nature. Nature teaches how to sustain, withdraw and advocate the prevailing situations. Some dwell into the deep realities of nature and nurture as ideal human beings. Life is a puzzle. How to solve it is a million dollar question that can never be answered so easily. The perception of life changes from individual to individual making them either physically powerful or feeble. Society is not made of only individuals. Along with individuals it has nature, emotions, spiritual powers and superstitious beliefs which bind them. Among them the most crucial and alarming is the emotions which are interrelated to others. Alone the emotional intelligence is going to guide the life of an individual. For everyone there is an inner self which makes them conscious of their deeds. The guiding force should always force the individual to choose the right path.  Writers are the powerful people who have rightly guided the society through their ingenious pen outs.  The present article is going to focus on how the major elements bound together are dominating the individual’s self through Rabindranath Tagore’s Home and the World (1916)


Sign in / Sign up

Export Citation Format

Share Document