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Sensory and Cognitive Adaptations to Social Living in Insect Societies Tom Wenseleersa,1 and Jelle S
COMMENTARY COMMENTARY Sensory and cognitive adaptations to social living in insect societies Tom Wenseleersa,1 and Jelle S. van Zwedena A key question in evolutionary biology is to explain the solitarily or form small annual colonies, depending upon causes and consequences of the so-called “major their environment (9). And one species, Lasioglossum transitions in evolution,” which resulted in the pro- marginatum, is even known to form large perennial euso- gressive evolution of cells, organisms, and animal so- cial colonies of over 400 workers (9). By comparing data cieties (1–3). Several studies, for example, have now from over 30 Halictine bees with contrasting levels of aimed to determine which suite of adaptive changes sociality, Wittwer et al. (7) now show that, as expected, occurred following the evolution of sociality in insects social sweat bee species invest more in sensorial machin- (4). In this context, a long-standing hypothesis is that ery linked to chemical communication, as measured by the evolution of the spectacular sociality seen in in- the density of their antennal sensillae, compared with sects, such as ants, bees, or wasps, should have gone species that secondarily reverted back to a solitary life- hand in hand with the evolution of more complex style. In fact, the same pattern even held for the socially chemical communication systems, to allow them to polymorphic species L. albipes if different populations coordinate their complex social behavior (5). Indeed, with contrasting levels of sociality were compared (Fig. whereas solitary insects are known to use pheromone 1, Inset). This finding suggests that the increased reliance signals mainly in the context of mate attraction and on chemical communication that comes with a social species-recognition, social insects use chemical sig- lifestyle indeed selects for fast, matching adaptations in nals in a wide variety of contexts: to communicate their sensory systems. -
Timeline of the Evolutionary History of Life
Timeline of the evolutionary history of life This timeline of the evolutionary history of life represents the current scientific theory Life timeline Ice Ages outlining the major events during the 0 — Primates Quater nary Flowers ←Earliest apes development of life on planet Earth. In P Birds h Mammals – Plants Dinosaurs biology, evolution is any change across Karo o a n ← Andean Tetrapoda successive generations in the heritable -50 0 — e Arthropods Molluscs r ←Cambrian explosion characteristics of biological populations. o ← Cryoge nian Ediacara biota – z ← Evolutionary processes give rise to diversity o Earliest animals ←Earliest plants at every level of biological organization, i Multicellular -1000 — c from kingdoms to species, and individual life ←Sexual reproduction organisms and molecules, such as DNA and – P proteins. The similarities between all present r -1500 — o day organisms indicate the presence of a t – e common ancestor from which all known r Eukaryotes o species, living and extinct, have diverged -2000 — z o through the process of evolution. More than i Huron ian – c 99 percent of all species, amounting to over ←Oxygen crisis [1] five billion species, that ever lived on -2500 — ←Atmospheric oxygen Earth are estimated to be extinct.[2][3] Estimates on the number of Earth's current – Photosynthesis Pong ola species range from 10 million to 14 -3000 — A million,[4] of which about 1.2 million have r c been documented and over 86 percent have – h [5] e not yet been described. However, a May a -3500 — n ←Earliest oxygen 2016 -
Studies of the Laboulbeniomycetes: Diversity, Evolution, and Patterns of Speciation
Studies of the Laboulbeniomycetes: Diversity, Evolution, and Patterns of Speciation The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:40049989 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA ! STUDIES OF THE LABOULBENIOMYCETES: DIVERSITY, EVOLUTION, AND PATTERNS OF SPECIATION A dissertation presented by DANNY HAELEWATERS to THE DEPARTMENT OF ORGANISMIC AND EVOLUTIONARY BIOLOGY in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Biology HARVARD UNIVERSITY Cambridge, Massachusetts April 2018 ! ! © 2018 – Danny Haelewaters All rights reserved. ! ! Dissertation Advisor: Professor Donald H. Pfister Danny Haelewaters STUDIES OF THE LABOULBENIOMYCETES: DIVERSITY, EVOLUTION, AND PATTERNS OF SPECIATION ABSTRACT CHAPTER 1: Laboulbeniales is one of the most morphologically and ecologically distinct orders of Ascomycota. These microscopic fungi are characterized by an ectoparasitic lifestyle on arthropods, determinate growth, lack of asexual state, high species richness and intractability to culture. DNA extraction and PCR amplification have proven difficult for multiple reasons. DNA isolation techniques and commercially available kits are tested enabling efficient and rapid genetic analysis of Laboulbeniales fungi. Success rates for the different techniques on different taxa are presented and discussed in the light of difficulties with micromanipulation, preservation techniques and negative results. CHAPTER 2: The class Laboulbeniomycetes comprises biotrophic parasites associated with arthropods and fungi. -
A Critique of Phanerozoic Climatic Models Involving Changes in The
Earth-Science Reviews 56Ž. 2001 1–159 www.elsevier.comrlocaterearscirev A critique of Phanerozoic climatic models involving changes in the CO2 content of the atmosphere A.J. Boucot a,), Jane Gray b,1 a Department of Zoology, Oregon State UniÕersity, CorÕallis, OR 97331, USA b Department of Biology, UniÕersity of Oregon, Eugene, OR 97403, USA Received 28 April 1998; accepted 19 April 2001 Abstract Critical consideration of varied Phanerozoic climatic models, and comparison of them against Phanerozoic global climatic gradients revealed by a compilation of Cambrian through Miocene climatically sensitive sedimentsŽ evaporites, coals, tillites, lateritic soils, bauxites, calcretes, etc.. suggests that the previously postulated climatic models do not satisfactorily account for the geological information. Nor do many climatic conclusions based on botanical data stand up very well when examined critically. Although this account does not deal directly with global biogeographic information, another powerful source of climatic information, we have tried to incorporate such data into our thinking wherever possible, particularly in the earlier Paleozoic. In view of the excellent correlation between CO2 present in Antarctic ice cores, going back some hundreds of thousands of years, and global climatic gradient, one wonders whether or not the commonly postulated Phanerozoic connection between atmospheric CO2 and global climatic gradient is more coincidence than cause and effect. Many models have been proposed that attempt to determine atmospheric composition and global temperature through geological time, particularly for the Phanerozoic or significant portions of it. Many models assume a positive correlation between atmospheric CO2 and surface temperature, thus viewing changes in atmospheric CO2 as playing the critical role in r regulating climate temperature, but none agree on the levels of atmospheric CO2 through time. -
Plasticity‐Led Evolution: a Survey of Developmental Mechanisms and Empirical Tests
DOI: 10.1111/ede.12309 PERSPECTIVE Plasticity‐led evolution: A survey of developmental mechanisms and empirical tests Nicholas A. Levis | David W. Pfennig Department of Biology, University of North Carolina, Chapel Hill, Abstract North Carolina Recent years have witnessed increased interest in evaluating whether phenotypic plasticity can precede, facilitate, and possibly even bias adaptive Correspondence “ ‐ ” Nicholas A. Levis, Department of Biology, evolution. Despite accumulating evidence for plasticity led evolution (i.e., CB#3280, University of North Carolina, “PLE”), critical gaps remain, such as: how different developmental Chapel Hill, NC 27599. mechanisms influence PLE; whether some types of traits and taxa are Email: [email protected] especially prone to experience PLE; and what studies are needed to drive the field forward. Here, we begin to address these shortcomings by first speculating about how various features of development—modularity, flexible regulation, and exploratory mechanisms—mightimpactand/orbias whether and how PLE unfolds. We then review and categorize the traits and taxa used to investigate PLE. We do so both to identify systems that may be well‐suited for studying developmental mechanisms in a PLE context and to highlight any mismatches between PLE theory and existing empirical tests of this theory. We conclude by providing additional suggestions for future research. Our overarching goal is to stimulate additional work on PLE and thereby evaluate plasticity’s role in evolution. 1 | INTRODUCTION 2011; West‐Eberhard, 2003). Under this view, novel traits start out evolutionarily as environmentally The environment has long been viewed as crucial in induced phenotypic variants. Later, they come under both selecting on phenotypes and in creating those genetic control through selection on developmental phenotypes in the first place (e.g., Baldwin, 1896, processes. -
Gene-Culture Coevolution, Group Selection, and the Evolution of Cooperation
EC_2018_A12 Gene-Culture coevolution, group selection, and the evolution of Cooperation The Evolution of Cooperation How can altruism / cooperation evolve? 1 EC_2018_A12 Levels of Selection "although a high standard of morality gives but a slight or no advantage to each individual man and his children over the other men of the same tribe (...) an advancement in the standard of morality will certainly give an immense advantage to one tribe over another.” (C. Darwin, Descent of Man, 1871) Levels of Selection Individuals (“basic” [Neo]Darwinism) Genes (“Selfish-gene” Sociobiology) Groups? Multilevel selection? Higher-level adaptations? Genetic Group Selection? “Naïve group selectionism”: The probability of survival of individual living things, or of populations, increases with the degree with which they harmoniously adjust themselves to each other and to their environment. This principle is basic to the concept of the balance of nature, orders the subject matter of ecology and evolution, underlies organismic and developmental biology, and is the foundation for all sociology. (Allee et al. 1949) “The good of the species” (Wynne-Edwards) 2 EC_2018_A12 Levels of Selection Migration, genetic drift, etc: Intergroup effects weaker than intragroup, interindividual selection. Intra x intergroup differences X Wilson DS & Wilson EO (2007) Rethinking the theoretical foundation of sociobiology Multi-level selection/ limits in kin selection theory/ “major transitions” Eusociality: Kin Selection X Individual selection + preadaptations. (communal nests) Nowak, Tarnita & Wilson, “The Evolution of Eusociality”, Nature 2010 (X Abbot et al [+100!], Nature 2011) “Major Transitions” in Evolution Maynard Smith & Szathmáry 1997 “Apart from the evolution of the genetic code, all these transitions involve the coming together of previously independent replicators, to cooperate in a higher-level assembly that reproduces as a single unit.” 3 EC_2018_A12 Natural selection & the evolution of cooperation Cooperation is needed for evolution to construct new levels of organization. -
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2 State of the World’s Fungi State of the World’s Fungi 2018 2. Fungal tree of life Ester Gayaa , Pepijn W. Kooija , Bryn T. M. Dentingerb, Igor V. Grigorievc, László G. Nagyd, Jason Stajiche, Timothy Cokera, Ilia J. Leitcha a Royal Botanic Gardens, Kew, UK; b Natural History Museum of Utah & School of Biological Sciences, University of Utah, USA; c U.S. Department of Energy Joint Genome Institute, USA; d Biological Research Centre, Hungarian Academy of Sciences, Hungary; e University of California-Riverside, USA 12 Describing the world’s fungi Fungal tree of life How are different species of fungi related to each other? What do we know about the major steps in fungal evolution and when they occurred? What are we doing about filling the knowledge gaps in the fungal tree of life? stateoftheworldsfungi.org/2018/fungal-tree-of-life.html Fungal tree of life 13 DNA data are providing new insights into the major steps that have taken place over the last 1 BILLION YEARS of fungal evolution 14 Describing the world’s fungi phyla[5], which we follow in this volume. In addition, these HOW ARE DIFFERENT SPECIES RELATED data are providing new insights into the major steps that have TO EACH OTHER? THIS SIMPLE YET taken place over the last 1 billion years of fungal evolution[5–7] (see Figure 1). CRITICALLY IMPORTANT QUESTION, 1. The earliest fungi. The earliest fungi are thought to have WHICH IS ROUTINELY ASKED ABOUT evolved around 1 billion years ago and to have been simple, single-celled organisms living in water and reproducing using SPECIES IN ALL KINGDOMS OF LIFE, motile asexual spores (zoospores) propelled by a posterior IS ONE OF THE MOST DIFFICULT TO whip-like structure called the flagellum[8,9]. -
Diversity of Entomopathogens Fungi: Which Groups Conquered
bioRxiv preprint doi: https://doi.org/10.1101/003756; this version posted April 4, 2014. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Diversity of entomopathogens Fungi: Which groups conquered the insect body? João P. M. Araújoa & David P. Hughesb aDepartment of Biology, Penn State University, University Park, Pennsylvania, United States of America. bDepartment of Entomology and Department of Biology, Penn State University, University Park, Pennsylvania, United States of America. [email protected]; [email protected]; Abstract The entomopathogenic Fungi comprise a wide range of ecologically diverse species. This group of parasites can be found distributed among all fungal phyla and as well as among the ecologically similar but phylogenetically distinct Oomycetes or water molds, that belong to a different kingdom (Stramenopila). As a group, the entomopathogenic fungi and water molds parasitize a wide range of insect hosts from aquatic larvae in streams to adult insects of high canopy tropical forests. Their hosts are spread among 18 orders of insects, in all developmental stages such as: eggs, larvae, pupae, nymphs and adults exhibiting completely different ecologies. Such assortment of niches has resulted in these parasites evolving a considerable morphological diversity, resulting in enormous biodiversity, much of which remains unknown. Here we gather together a huge amount of records of these entomopathogens to comparing and describe both their morphologies and ecological traits. These findings highlight a wide range of adaptations that evolved following the evolutionary transition to infecting the most diverse and widespread animals on Earth, the insects. -
Identification of Culture-Negative Fungi in Blood and Respiratory Samples
IDENTIFICATION OF CULTURE-NEGATIVE FUNGI IN BLOOD AND RESPIRATORY SAMPLES Farida P. Sidiq A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2014 Committee: Scott O. Rogers, Advisor W. Robert Midden Graduate Faculty Representative George Bullerjahn Raymond Larsen Vipaporn Phuntumart © 2014 Farida P. Sidiq All Rights Reserved iii ABSTRACT Scott O. Rogers, Advisor Fungi were identified as early as the 1800’s as potential human pathogens, and have since been shown as being capable of causing disease in both immunocompetent and immunocompromised people. Clinical diagnosis of fungal infections has largely relied upon traditional microbiological culture techniques and examination of positive cultures and histopathological specimens utilizing microscopy. The first has been shown to be highly insensitive and prone to result in frequent false negatives. This is complicated by atypical phenotypes and organisms that are morphologically indistinguishable in tissues. Delays in diagnosis of fungal infections and inaccurate identification of infectious organisms contribute to increased morbidity and mortality in immunocompromised patients who exhibit increased vulnerability to opportunistic infection by normally nonpathogenic fungi. In this study we have retrospectively examined one-hundred culture negative whole blood samples and one-hundred culture negative respiratory samples obtained from the clinical microbiology lab at the University of Michigan Hospital in Ann Arbor, MI. Samples were obtained from randomized, heterogeneous patient populations collected between 2005 and 2006. Specimens were tested utilizing cetyltrimethylammonium bromide (CTAB) DNA extraction and polymerase chain reaction amplification of internal transcribed spacer (ITS) regions of ribosomal DNA utilizing panfungal ITS primers. -
Genetic Accommodation and the Role of Ancestral Plasticity in the Evolution of Insect Eusociality Beryl M
© 2018. Published by The Company of Biologists Ltd | Journal of Experimental Biology (2018) 221, jeb153163. doi:10.1242/jeb.153163 COMMENTARY Genetic accommodation and the role of ancestral plasticity in the evolution of insect eusociality Beryl M. Jones1,* and Gene E. Robinson1,2,3,4 ABSTRACT novel genetic combinations and phenotypes (Carroll, 2008). ‘ ’ For over a century, biologists have proposed a role for phenotypic Mutation-first evolution (see Glossary), where a new mutation ‘ ’ plasticity in evolution, providing an avenue for adaptation in addition provides novel phenotypes that can be screened by natural to ‘mutation-first’ models of evolutionary change. According to the selection, is easily studied when the mutation can be directly linked various versions of this idea, the ability of organisms to respond to the phenotype. Even without knowledge of the phenotypic adaptively to their environment through phenotypic plasticity may consequences of alleles, mutation-first evolution studies can be lead to novel phenotypes that can be screened by natural selection. If initiated in both natural populations and laboratories simply by these initially environmentally induced phenotypes increase fitness, documenting changes in allele frequencies over time. then genetic accommodation can lead to allele frequency change, However, novel traits are also suggested to originate independent influencing the expression of those phenotypes. Despite the long of new mutations, via the environmental and developmental history of ‘plasticity-first’ models, the importance of genetic induction of phenotypes. One of the first biologists to emphasize accommodation in shaping evolutionary change has remained this was Baldwin, who at the turn of the 20th century suggested a ‘ ’ controversial – it is neither fully embraced nor completely discarded process of organic selection by which fitness differences arising by most evolutionary biologists. -
Enforcement Is Central to the Evolution of Cooperation
REVIEW ARTICLE https://doi.org/10.1038/s41559-019-0907-1 Enforcement is central to the evolution of cooperation J. Arvid Ågren1,2,6, Nicholas G. Davies 3,6 and Kevin R. Foster 4,5* Cooperation occurs at all levels of life, from genomes, complex cells and multicellular organisms to societies and mutualisms between species. A major question for evolutionary biology is what these diverse systems have in common. Here, we review the full breadth of cooperative systems and find that they frequently rely on enforcement mechanisms that suppress selfish behaviour. We discuss many examples, including the suppression of transposable elements, uniparental inheritance of mito- chondria and plastids, anti-cancer mechanisms, reciprocation and punishment in humans and other vertebrates, policing in eusocial insects and partner choice in mutualisms between species. To address a lack of accompanying theory, we develop a series of evolutionary models that show that the enforcement of cooperation is widely predicted. We argue that enforcement is an underappreciated, and often critical, ingredient for cooperation across all scales of biological organization. he evolution of cooperation is central to all living systems. A major open question, then, is what, if anything, unites the Evolutionary history can be defined by a series of major tran- evolution of cooperative systems? Here, we review cooperative evo- Tsitions (Box 1) in which replicating units came together, lost lution across all levels of biological organization, which reveals a their independence and formed new levels of biological organiza- growing amount of evidence for the importance of enforcement. tion1–4. As a consequence, life is organized in a hierarchy of coop- By enforcement, we mean an action that evolves, at least in part, to eration: genes work together in genomes, genomes in cells, cells in reduce selfish behaviour within a cooperative alliance (see Box 2 for multicellular organisms and multicellular organisms in eusocial the formal definition). -
Insects with Similar Social Complexity Show Convergent Patterns Of
www.nature.com/scientificreports OPEN Insects with similar social complexity show convergent patterns of adaptive molecular Received: 13 December 2017 Accepted: 22 June 2018 evolution Published: xx xx xxxx Kathleen A. Dogantzis1, Brock A. Harpur 1,2, André Rodrigues3, Laura Beani4, Amy L. Toth5 & Amro Zayed 1 Eusociality has independently evolved multiple times in the hymenoptera, but the patterns of adaptive molecular evolution underlying the evolution and elaboration of eusociality remain uncertain. Here, we performed a population genomics study of primitively eusocial Polistes (paper wasps), and compared their patterns of molecular evolution to two social bees; Bombus (bumblebees), and Apis (honey bees). This species triad allowed us to study molecular evolution across a gradient of social complexity (Polistes < Bombus < Apis) and compare species pairs that have similar (i.e. Polistes and Bombus) or diferent (i.e. Polistes and Apis) life histories, while controlling for phylogenetic distance. We found that regulatory genes have high levels of positive selection in Polistes; consistent with the prediction that adaptive changes in gene regulation are important during early stages of social evolution. Polistes and Bombus exhibit greater similarity in patterns of adaptive evolution including greater overlap of genes experiencing positive selection, and greater positive selection on queen-biased genes. Our fndings suggest that either adaptive evolution of a few key genes underlie the evolution of simpler forms of eusociality, or that the initial stages of social evolution lead to selection on a few key traits orchestrated by orthologous genes and networks. Understanding the origin and elaboration of eusociality is a major goal of evolutionary biology.