Progress and Competition in Macroevolution
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Alfred Russel Wallace and the Darwinian Species Concept
Gayana 73(2): Suplemento, 2009 ISSN 0717-652X ALFRED RUSSEL WALLACE AND THE Darwinian SPECIES CONCEPT: HIS paper ON THE swallowtail BUTTERFLIES (PAPILIONIDAE) OF 1865 ALFRED RUSSEL WALLACE Y EL concepto darwiniano DE ESPECIE: SU TRABAJO DE 1865 SOBRE MARIPOSAS papilio (PAPILIONIDAE) Jam ES MA LLET 1 Galton Laboratory, Department of Biology, University College London, 4 Stephenson Way, London UK, NW1 2HE E-mail: [email protected] Abstract Soon after his return from the Malay Archipelago, Alfred Russel Wallace published one of his most significant papers. The paper used butterflies of the family Papilionidae as a model system for testing evolutionary hypotheses, and included a revision of the Papilionidae of the region, as well as the description of some 20 new species. Wallace argued that the Papilionidae were the most advanced butterflies, against some of his colleagues such as Bates and Trimen who had claimed that the Nymphalidae were more advanced because of their possession of vestigial forelegs. In a very important section, Wallace laid out what is perhaps the clearest Darwinist definition of the differences between species, geographic subspecies, and local ‘varieties.’ He also discussed the relationship of these taxonomic categories to what is now termed ‘reproductive isolation.’ While accepting reproductive isolation as a cause of species, he rejected it as a definition. Instead, species were recognized as forms that overlap spatially and lack intermediates. However, this morphological distinctness argument breaks down for discrete polymorphisms, and Wallace clearly emphasised the conspecificity of non-mimetic males and female Batesian mimetic morphs in Papilio polytes, and also in P. -
Unit-V Evolution of Horse
UNIT-V EVOLUTION OF HORSE Horses (Equus) are odd-toed hooped mammals belong- ing to the order Perissodactyla. Horse evolution is a straight line evolution and is a suitable example for orthogenesis. It started from Eocene period. The entire evolutionary sequence of horse history is recorded in North America. " Place of Origin The place of origin of horse is North America. From here, horses migrated to Europe and Asia. By the end of Pleis- tocene period, horses became extinct in the motherland (N. America). The horses now living in N. America are the de- scendants of migrants from other continents. Time of Origin The horse evolution started some 58 million years ago, m the beginning of Eocene period of Coenozoic era. The modem horse Equus originated in Pleistocene period about 2 million years ago. Evolutionary Trends The fossils of horses that lived in different periods, show that the body parts exhibited progressive changes towards a particular direction. These directional changes are called evo- lutionary trends. The evolutionary trends of horse evolution are summarized below: 1. Increase in size. 2. Increase in the length of limbs. 3. Increase in the length of the neck. 4. Increase in the length of preorbital region (face). 5. Increase in the length and size of III digit. 6. Increase in the size and complexity of brain. 7. Molarization of premolars. Olfactory bulb Hyracotherium Mesohippus Equus Fig.: Evolution of brain in horse. 8. Development of high crowns in premolars and molars. 9. Change of plantigrade gait to unguligrade gait. 10. Formation of diastema. 11. Disappearance of lateral digits. -
Genomics and the Evolutionary History of Equids Pablo Librado, Ludovic Orlando
Genomics and the Evolutionary History of Equids Pablo Librado, Ludovic Orlando To cite this version: Pablo Librado, Ludovic Orlando. Genomics and the Evolutionary History of Equids. Annual Review of Animal Biosciences, Annual Reviews, 2021, 9 (1), 10.1146/annurev-animal-061220-023118. hal- 03030307 HAL Id: hal-03030307 https://hal.archives-ouvertes.fr/hal-03030307 Submitted on 30 Nov 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Annu. Rev. Anim. Biosci. 2021. 9:X–X https://doi.org/10.1146/annurev-animal-061220-023118 Copyright © 2021 by Annual Reviews. All rights reserved Librado Orlando www.annualreviews.org Equid Genomics and Evolution Genomics and the Evolutionary History of Equids Pablo Librado and Ludovic Orlando Laboratoire d’Anthropobiologie Moléculaire et d’Imagerie de Synthèse, CNRS UMR 5288, Université Paul Sabatier, Toulouse 31000, France; email: [email protected] Keywords equid, horse, evolution, donkey, ancient DNA, population genomics Abstract The equid family contains only one single extant genus, Equus, including seven living species grouped into horses on the one hand and zebras and asses on the other. In contrast, the equine fossil record shows that an extraordinarily richer diversity existed in the past and provides multiple examples of a highly dynamic evolution punctuated by several waves of explosive radiations and extinctions, cross-continental migrations, and local adaptations. -
Evolution Activity, Grade 11
Evolution Activity, Grade 11 Evolution Activities for Grade 11 Students at the Toronto Zoo 1 Evolution Activity, Grade 11 Table of Contents Pre-Zoo Activity 3-8 • Think, Pair, Share – Animals in Society and Role of Zoos 3-5 o Description 3 o Materials 3 o Four Corners Activity 6 o Background Information 7-8 Zoo Activity 9-19 • Teacher’s Notes 9-13 o General Information, Curriculum expectations, 9-10 materials, procedure o Evaluation Rubrics 11-12 o Glossary 13 • Student Assignment 14-19 o Part 1 – Mission Preparation at the Zoo 15-16 (Observation Sheets) o Part 2 – Scientific Notes 17 o Part 3 – Documentation: The Story 18 o Appendix – Animal signs 19 Evaluation 20 2 Evolution Activity, Grade 11 Suggested Pre-zoo activity Time needed : 35 minutes (or more) Type of activity : pair-share, small-group (approximately 2-3 students) Objective : encourage students to think about and evaluate the roles of animals in our society and the purposes of zoos along with their own attitudes or stands toward zoos Materials needed : a set of 8-16 statements and a mode of ranking (either above the line-below the line or diamond style ranking system) Special note : In order to manage time, teacher can chose to use any number of the statements as long as the 4 core statements listed bellow are included. Task : students work together to rank the statements about the treatment of animals. They should work together and try to negotiate a consensus, but if this is impossible they can either leave out the particular statement or write down a few lines in their notes as to why they would place them in a different category. -
Countershading in Zebrafish Results from an Asip1 Controlled
www.nature.com/scientificreports OPEN Countershading in zebrafsh results from an Asip1 controlled dorsoventral gradient of pigment Received: 1 October 2018 Accepted: 12 February 2019 cell diferentiation Published: xx xx xxxx Laura Cal1, Paula Suarez-Bregua1, Pilar Comesaña1, Jennifer Owen2, Ingo Braasch3, Robert Kelsh 2, José Miguel Cerdá-Reverter4 & Josep Rotllant1 Dorso-ventral (DV) countershading is a highly-conserved pigmentary adaptation in vertebrates. In mammals, spatially regulated expression of agouti-signaling protein (ASIP) generates the diference in shading by driving a switch between the production of chemically-distinct melanins in melanocytes in dorsal and ventral regions. In contrast, fsh countershading seemed to result from a patterned DV distribution of diferently-coloured cell-types (chromatophores). Despite the cellular diferences in the basis for counter-shading, previous observations suggested that Agouti signaling likely played a role in this patterning process in fsh. To test the hypotheses that Agouti regulated counter-shading in fsh, and that this depended upon spatial regulation of the numbers of each chromatophore type, we engineered asip1 homozygous knockout mutant zebrafsh. We show that loss-of-function asip1 mutants lose DV countershading, and that this results from changed numbers of multiple pigment cell-types in the skin and on scales. Our fndings identify asip1 as key in the establishment of DV countershading in fsh, but show that the cellular mechanism for translating a conserved signaling gradient into a conserved pigmentary phenotype has been radically altered in the course of evolution. Most vertebrates exhibit a dorso-ventral pigment pattern characterized by a light ventrum and darkly colored dorsal regions. Tis countershading confers UV protection against solar radiation, but also is proposed to pro- vide anti-predator cryptic pigmentation. -
Skeleton of the Oligocene (30 Million-Year-Old) Horse, Mesohippus, Is a Featured Exhibit at the New North Dakota Cowboy Hall of Fame in Medora
Skeleton of the Oligocene (30 million-year-old) horse, Mesohippus, is a featured exhibit at the new North Dakota Cowboy Hall of Fame in Medora By John W. Hoganson Developers of the recently opened North Dakota Cowboy Hall of Fame contacted me about having a fossil exhibit in the new Hall in Medora. Of course, what would be more appropriate than an exhibit interpreting the evolution of the horse? Most people are under the false impression that horses did not inhabit North America until they were introduced by the Spaniards during the early days of conquest. But horses are indigenous to North America. Fossil remains of the earliest horse, referred to as Hyracotherium (or sometimes Eohippus), have been recovered from early Eocene (about 50 million years old) rocks in North America. In fact, they were some of the most abundant mammals that lived during that time. The fossil record of horses in North Dakota extends back to the Oligocene, about 30 million years ago, when the diminutive horse, Mesohippus roamed western North Dakota. Mesohippus was tiny, about the size of a sheep. The adults were only about 20 inches tall at the shoulder. They also had three toes on each foot compared to the modern horse Equus that has one. Mesohippus was also probably more of a browsing herbivore compared to the modern grazing horse. We have found many Mesohippus fossils in North Dakota but no complete skeletons. Consequently, the Mesohippus skeleton on exhibit at the Cowboy Hall of Fame is an exact cast replica. We have also found the remains of 50,000-year-old horses in North Dakota indicating that horses lived here during the last Ice Age. -
Convergent Evolution of Seasonal Camouflage in Response to Reduced Snow Cover Across the Snowshoe Hare Range
ORIGINAL ARTICLE doi:10.1111/evo.13976 Convergent evolution of seasonal camouflage in response to reduced snow cover across the snowshoe hare range Matthew R. Jones,1,2 L. Scott Mills,3,4 Jeffrey D. Jensen,5 and Jeffrey M. Good1,3,6 1Division of Biological Sciences, University of Montana, Missoula, Montana 59812 2E-mail: [email protected] 3Wildlife Biology Program, University of Montana, Missoula, Montana 59812 4Office of Research and Creative Scholarship, University of Montana, Missoula, Montana 59812 5School of Life Sciences, Arizona State University, Tempe, Arizona 85281 6E-mail: [email protected] Received January 22, 2020 Accepted April 2, 2020 Determining how different populations adapt to similar environments is fundamental to understanding the limits of adaptation under changing environments. Snowshoe hares (Lepus americanus) typically molt into white winter coats to remain camouflaged against snow. In some warmer climates, hares have evolved brown winter camouflage—an adaptation that may spread in re- sponse to climate change. We used extensive range-wide genomic data to (1) resolve broad patterns of population structure and gene flow and (2) investigate the factors shaping the origins and distribution of winter-brown camouflage variation. Incoastal Pacific Northwest (PNW) populations, winter-brown camouflage is known to be determined by a recessive haplotype atthe Agouti pigmentation gene. Our phylogeographic analyses revealed deep structure and limited gene flow between PNW and more north- ern Boreal populations, where winter-brown camouflage is rare along the range edge. Genome sequencing of a winter-brown snowshoe hare from Alaska shows that it lacks the winter-brown PNW haplotype, reflecting a history of convergent phenotypic evolution. -
The Molecular Basis of Phenotypic Convergence
ES45CH10-Rosenblum ARI 15 October 2014 11:31 The Molecular Basis of Phenotypic Convergence Erica Bree Rosenblum,1 Christine E. Parent,1,2 and Erin E. Brandt1 1Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720; email: [email protected], [email protected] 2Department of Biological Sciences, University of Idaho, Moscow, Idaho 83844; email: [email protected] Annu. Rev. Ecol. Evol. Syst. 2014. 45:203–26 Keywords First published online as a Review in Advance on convergent evolution, parallelism, genetics, nonmodel species September 29, 2014 The Annual Review of Ecology, Evolution, and Abstract Systematics is online at ecolsys.annualreviews.org Understanding what aspects of evolution are predictable, and repeatable, is a This article’s doi: central goal of biology. Studying phenotypic convergence (the independent 10.1146/annurev-ecolsys-120213-091851 evolution of similar traits in different organisms) provides an opportunity to Copyright c 2014 by Annual Reviews. address evolutionary predictability at different hierarchical levels. Here we All rights reserved focus on recent advances in understanding the molecular basis of conver- Annu. Rev. Ecol. Evol. Syst. 2014.45:203-226. Downloaded from www.annualreviews.org Access provided by University of California - Berkeley on 01/30/15. For personal use only. gence. Understanding when, and why, similar molecular solutions are used repeatedly provides insight into the constraints that shape biological diver- sity. We first distinguish between convergence as a phenotypic pattern and parallelism as a shared molecular basis for convergence. We then address the overarching question: What factors influence when parallel molecular mechanisms will underlie phenotypic convergence? We present four core determinants of convergence (natural selection, phylogenetic history, pop- ulation demography, and genetic constraints) and explore specific factors that influence the probability of molecular parallelism. -
(Non)Parallel Evolution 3 4 Daniel I. Bolnick1,2*, Rowan Barrett3, Krista
1 2 3 (Non)Parallel Evolution 4 5 Daniel I. Bolnick1,2*, Rowan Barrett3, Krista Oke3,4 , Diana J. Rennison5 , Yoel E. Stuart1 6 7 1 Department of Integrative Biology, University of Texas at Austin, Austin TX 78712, USA; 8 [email protected]; [email protected] 9 2 Department of Ecology and Evolution, University of Connecticut, Storrs CT 06268, USA (as of 10 07/2018) 11 3 Redpath Museum, McGill University, Montreal, Quebec, Canada; [email protected] 12 4 Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa 13 Cruz, CA, 95060, USA; [email protected] 14 5 Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland; 15 [email protected] 16 17 * Corresponding author: Email: [email protected] Telephone: +011 (512) 471-2824 18 19 20 Running title: “(Non)Parallel Evolution” 21 22 1 23 Abstract 24 Parallel evolution across replicate populations has provided evolutionary biologists with iconic 25 examples of adaptation. When multiple populations colonize seemingly similar habitats, they 26 may evolve similar genes, traits, or functions. Yet, replicated evolution in nature or in the lab 27 often yields inconsistent outcomes: some replicate populations evolve along highly similar 28 trajectories, whereas other replicate populations evolve to different extents or in atypical 29 directions. To understand these heterogeneous outcomes, biologists are increasingly treating 30 parallel evolution not as a binary phenomenon but rather as a quantitative continuum ranging 31 from nonparallel to parallel. By measuring replicate populations’ positions along this 32 “(non)parallel” continuum, we can test hypotheses about evolutionary and ecological factors that 33 influence the likelihood of repeatable evolution. -
Convergent Evolution
Exploring the KU Natural History Museum Convergent Evolution Target Audience: Middle school and above Differentiated Instruction Summary Strategy Levels Content/Process/Product Grouping(s) Learning modalities Whole group • Level 1 – Visual (spatial) Small groups Process Cubing Level 2 – Kinesthetic (physical) Peer partners • Product • Level 3 – Verbal (linguistic) Homogeneous Heterogeneous * Varied grouping options can be used for this activity, depending on student needs and chaperone ability. Objectives: Explore examples of convergent evolution in vertebrates. Pre-assessment/Prior Knowledge: Prior to their visit, students should be familiar with the idea of convergent evolution, overall evolutionary relationships/classification of vertebrate groups and basic anatomy of those groups. Activity Description: Students explore the idea of convergent evolution through museum exhibits through different learning modalities. Materials Needed: • Student o Cubes (three levels, see attached) o Paper and pencils (alternatively you could use flipchart paper and markers, whiteboards and dry erase markers) o Optional (cell phones or other recording device for visual or kinesthetic levels) Note: Format to record/present findings determined by individual teacher. Provide clear instructions about expectations for documenting participation, particularly for verbal/spatial and body/kinesthetic levels (e.g. stage direction, audio/video recording). • Teacher o Content Outline o Cube labels o Cube template Content: Convergence Overview Convergent evolution refers to the similarities in biological traits that arise independently in organisms that are not closely related, e.g. wings in birds, bats and insects. Similarity among organisms and their structures that was not inherited from a common ancestor is considered to be homoplasy. This can be contrasted with homology, which refers to similarity of traits due to common ancestry. -
The Genetic Causes of Convergent Evolution
Nature Reviews Genetics | AOP, published online 9 October 2013; doi:10.1038/nrg3483 REVIEWS The genetic causes of convergent evolution David L. Stern Abstract | The evolution of phenotypic similarities between species, known as convergence, illustrates that populations can respond predictably to ecological challenges. Convergence often results from similar genetic changes, which can emerge in two ways: the evolution of similar or identical mutations in independent lineages, which is termed parallel evolution; and the evolution in independent lineages of alleles that are shared among populations, which I call collateral genetic evolution. Evidence for parallel and collateral evolution has been found in many taxa, and an emerging hypothesis is that they result from the fact that mutations in some genetic targets minimize pleiotropic effects while simultaneously maximizing adaptation. If this proves correct, then the molecular changes underlying adaptation might be more predictable than has been appreciated previously. (FIG. 1) Fitness Different species often evolve similar solutions to envi introgression . It is worth distinguishing between The potential evolutionary ronmental challenges. Insects, birds and bats evo these scenarios because each provides evidence for a dif success of a genotype, defined lved wings, and octopi, vertebrates and spiders ferent evolutionary path3. The first case, the independent as the reproductive success or evolved focusing eyes. Phenotypic convergence provides origin and spread of mutations, has been called parallel the proportion of genes that an individual leaves in the gene compelling evidence that ecological circumstances can genetic evolution. I suggest that the evolution of alleles 1,2 pool of the next generation in a select for similar evolutionary solutions . -
Phylogeny of the Procyonidae (Mammalia: Carnivora): Molecules, Morphology and the Great American Interchange
Molecular Phylogenetics and Evolution 43 (2007) 1076–1095 www.elsevier.com/locate/ympev Phylogeny of the Procyonidae (Mammalia: Carnivora): Molecules, morphology and the Great American Interchange a, b c a Klaus-Peter KoepXi ¤, Matthew E. Gompper , Eduardo Eizirik , Cheuk-Chung Ho , Leif Linden a, Jesus E. Maldonado d, Robert K. Wayne a a Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA b Department of Fisheries and Wildlife Sciences, University of Missouri, Colombia, MO 65211, USA c Faculdade de Biociencias, PUCRS, Av. Ipiranga, 6681, Predio 12, Porto Alegre, RS 90619-900, Brazil d Smithsonian Institution, NMNH/NZP—Genetic Program, 3001 Connecticut Avenue NW, Washington, DC 20008, USA Received 10 June 2006; revised 22 September 2006; accepted 2 October 2006 Available online 11 October 2006 Abstract The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morpho- logical characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. SpeciWcally, the highly arboreal and frugivorous kinkajou (Potos Xavus) and olingos (Bassaricyon) deWne one clade, whereas the more terrestrial and omnivorous coatis (Nasua), raccoons (Procyon), and ringtails (Bassariscus) deWne another clade, with the similar-sized Nasua and Procyon joined as sister taxa in this latter group. These relationships, however, have not been tested with molecu- lar sequence data. We examined procyonid phylogenetics based on combined data from nine nuclear and two mitochondrial gene seg- ments totaling 6534 bp.