DOCSLIB.ORG

Evolution in Four Dimensions Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life Eva Jablonka and Marion J

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Evolution in Four Dimensions Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life Eva Jablonka and Marion J Book review Evolution in four dimensions Genetic, epigenetic, behavioral, and symbolic variation in the history of life Eva Jablonka and Marion J. Lamb The MIT Press. Cambridge, Massachusetts, USA. 2005. 472 pp. $34.95. ISBN: 0-262-10107-6 (hardcover). Reviewed by Mike Benton University of Bristol, Bristol, United Kingdom. E-mail: [email protected]. In Evolution in four dimensions: genetic, epi- with genes for loss of cross veins; the heat impinge on evolution through assimilation. genetic, behavioral, and symbolic variation in shocking was irrelevant. Genetic assimila- Their take on the cream-drinking tits is that the history of life, Eva Jablonka and Marion J. tion was Lamarckism under a new name. learned behavior can become innate if it is Lamb make a concerted effort to expand on Studies of behavior also brought chal- selectively important. If survival through evolutionary theory. The book is one of the lenges. Another study done in Britain in the winter depends on cream drinking, tits best written that I have read in years: clear, the 1940s suggested Lamarckism. Great tits that learn fast would survive best. It would succinct, thoroughly signposted, and with and blue tits “learned” to pick open the foil then be the propensity to learn fast that is ample summaries and reviews of difficult tops of milk bottles and drink the cream selected for. Over time, the authors suggest, areas. The illustrations by Anna Zeligowski on top. The habit spread throughout the what is learned is learned faster and faster are excellent. The care in writing and the country and passed from generation to gen- through the generations until it becomes attractive format should not, however, eration, so it was, in a loose sense, inherited. encoded in the genotype. But how? No one mask the fact that the authors are attempt- Some analysts have since characterized such has yet shown that assimilation happens — ing something revolutionary — a complete behavioral transmission as a kind of evolu- how can it be distinguished from selection rethinking of evolutionary theory. tion, where the behavioral trait is termed a for learning fast or having no cross veins? Lamarckism is alive and well — or is it? meme. In memetics, transmission of such This is where the authors’ thesis seems to Jean-Baptiste Lamarck (1744–1829) is behavior is Lamarckian: it was acquired by fall down. Their case studies can be explained remembered for only a small part of his one or more birds during their lifetimes, and by simple natural selection. Behavior is part writings on evolution, what we now call the the meme was then passed down. of the phenotype, as are developmental inheritance of acquired characters. Lamarck As Jablonka and Lamb point out, the con- pathways and some fundamental aspects of believed that giraffes strove to reach higher cepts of memes and memetics are nonsense, the human ability to learn language. So the leaves, resulting in elongated necks over time. bearing no relation to genes and genetics. “four dimensions” become one again. Modern Darwinian evolutionary theory does Genes are real entities, copied and transmit- Other authors have tried to expand on not allow for such transmission of acquired ted through generations. The meme for bot- evolution before, yet their efforts have rarely characters. Increasing numbers of observa- tle opening by tits is a chance observation; met with enthusiasm for long. The late Steve tions and intuitions, however, seem to point its bounds are determined by the observer. Gould sought to expand on evolution by to something Lamarckian in evolution. There is no concrete entity, nothing to be adding new hierarchical levels, especially in Jablonka and Lamb begin by discussing copied and transmitted. Milk bottles with the realm of macroevolution. I believed him genetic assimilation, proposed in 1942 by foil tops are rare in Britain now, but some for a while because I, like Gould, am a pale- British geneticist and embryologist C.H. birds still filch the cream. Has the meme ontologist, and it was encouraging to believe Waddington. Waddington treated the pupae survived, or have birds reinvented the behav- that the long time scales offered uniquely of fruit flies with heat shock, causing many ior from time to time? These are interesting by the fossil record allowed us to detect new of the flies to have abnormal wings lacking questions, but wrapping the behavior up as kinds of evolutionary phenomena. But the cross veins. Waddington bred these flies, a meme is neither here nor there. critics were right; in theory, species selection repeating the treatments for generations, Jablonka and Lamb, however, hang onto could happen, but an example has yet to be and eventually found that flies without Waddington’s concept of genetic assimi- convincingly demonstrated. Likewise, I have cross veins emerged from pupae that had lation and extend it to develop ideas of to conclude that though the experiments are not been heat treated. He then argued that “behavioral assimilation” and “symbolic fascinating and the case studies intriguing, an acquired character had been assimilated assimilation.” The four dimensions in the none of them indicates that natural selection into the genetic code of the flies, thereby title of the book refer to evolution as quad- has to admit epigenetic, behavioral, and sym- breaking the neo-Darwinian rule that there ripartite: genetic, epigenetic (developmen- bolic inheritance as separate, let alone quasi- can be no information transmission from tal), behavioral, and symbolic (linguistic). equal, processes. I loved the book, admire phenotype to genotype. Strict Darwinians Jablonka and Lamb argue that develop- the authors intensely, and wish I could agree argued that Waddington had selected flies mental, behavioral, and linguistic attributes with their thesis. The Journal of Clinical Investigation http://www.jci.org Volume 115 Number 11 November 2005 2961.
Load more

Recommended publications
  • On Good Memories and Group-Living Meerkats
    Arbeitsberichte 91 Eva Jablonka On Good Memories and Group-Living Meerkats Eva Jablonka was born in Poland in 1952 and immi- grated to Israel in 1957. She studied for her B.Sc. at Birkbeck College, University of London and Ben Gurion University, Israel, and obtained an M.Sc. in microbiology from Ben Gurion University. Research for a Ph.D. in molecular genetics was carried out at the Hebrew University, Jerusalem. Post-doctoral studies in developmental biology and the philosophy of science followed. Since 1993, she has been a ten- ured Senior Lecturer in the Department of the His- tory and Philosophy of Science, Tel-Aviv University, teaching evolutionary biology, genetics, the philoso- phy of biology, and the history of genetics. Major publications: Epigenetic Inheritance and Evolution: the Lamarckian Dimension 1995, OUP (with Marion Lamb); The History of Heredity 1994 (The Broad- casting University, TA); Evolution 1994–1997 (A textbook in evolutionary biology for the Open Uni- versity of Israel, Open University Press, Israel). Research interests: evolutionary biology, genetics, behavioural ecology, the history and philosophy of biology. – Address: The Cohn Institute for the His- tory and Philosophy of Science and Ideas, Tel Aviv University, Ramat Aviv, 69978 Tel-Aviv, Israel. As I sit here in my office in the Villa Jaffé trying to write this report, I look out of the window, beyond the blue screen of my computer, wondering how I can convey the complex and rich experiences that I have had here. New intellectual terrains opened up, new friendships blossomed. A red squirrel jumps through the green foliage of the oak tree just next to the window, the sun shines through the leaves, and my room is full of light and dancing shadows.
    [Show full text]
  • Transformations of Lamarckism Vienna Series in Theoretical Biology Gerd B
    Transformations of Lamarckism Vienna Series in Theoretical Biology Gerd B. M ü ller, G ü nter P. Wagner, and Werner Callebaut, editors The Evolution of Cognition , edited by Cecilia Heyes and Ludwig Huber, 2000 Origination of Organismal Form: Beyond the Gene in Development and Evolutionary Biology , edited by Gerd B. M ü ller and Stuart A. Newman, 2003 Environment, Development, and Evolution: Toward a Synthesis , edited by Brian K. Hall, Roy D. Pearson, and Gerd B. M ü ller, 2004 Evolution of Communication Systems: A Comparative Approach , edited by D. Kimbrough Oller and Ulrike Griebel, 2004 Modularity: Understanding the Development and Evolution of Natural Complex Systems , edited by Werner Callebaut and Diego Rasskin-Gutman, 2005 Compositional Evolution: The Impact of Sex, Symbiosis, and Modularity on the Gradualist Framework of Evolution , by Richard A. Watson, 2006 Biological Emergences: Evolution by Natural Experiment , by Robert G. B. Reid, 2007 Modeling Biology: Structure, Behaviors, Evolution , edited by Manfred D. Laubichler and Gerd B. M ü ller, 2007 Evolution of Communicative Flexibility: Complexity, Creativity, and Adaptability in Human and Animal Communication , edited by Kimbrough D. Oller and Ulrike Griebel, 2008 Functions in Biological and Artifi cial Worlds: Comparative Philosophical Perspectives , edited by Ulrich Krohs and Peter Kroes, 2009 Cognitive Biology: Evolutionary and Developmental Perspectives on Mind, Brain, and Behavior , edited by Luca Tommasi, Mary A. Peterson, and Lynn Nadel, 2009 Innovation in Cultural Systems: Contributions from Evolutionary Anthropology , edited by Michael J. O ’ Brien and Stephen J. Shennan, 2010 The Major Transitions in Evolution Revisited , edited by Brett Calcott and Kim Sterelny, 2011 Transformations of Lamarckism: From Subtle Fluids to Molecular Biology , edited by Snait B.
    [Show full text]
  • A Role for Genetic Accommodation in Evolution? Christian Braendle1* and Thomas Flatt2
    What the papers say A role for genetic accommodation in evolution? Christian Braendle1* and Thomas Flatt2 Summary lowered. Third, selection in the presence of the environmental Whether evolutionary change can occur by genetic factor enriches the previously cryptic alleles determining assimilation, or more generally by genetic accommoda- tion, remains controversial. Here we examine some of the the trait. Eventually, these alleles become so frequent that experimental evidence for both phenomena. Several the expression of the trait overcomes the higher threshold in experiments in Drosophila suggest that assimilation is the absence of the environmental stimulus.(9,20) Thus, genetic (1) possible, and a new paper shows that a color poly- assimilation transforms an environmentally induced (pheno- phenism in the tobacco hornworm, Manduca sexta, can typically plastic) trait into a phenotype which is stably evolve by genetic accommodation. We argue that genetic accommodation, including assimilation, is a plausible expressed without the eliciting environmental stimulus: the mechanism in evolution; however, more work is required genetically assimilated phenotype is no longer plastic, but to test how this mechanism acts and how often it is exhibits a genetically fixed response independent of the involved in evolutionary change. BioEssays 28:868– environmental conditions,(2,9,14,16) a phenomenon called 873, 2006. ß 2006 Wiley Periodicals, Inc. canalization.(20) Genetic assimilation is a special case of a more general Genetic assimilation and accommodation phenomenon, called genetic accommodation, most promi- (2–9) Whether the processes of genetic assimilation and nently proposed by Mary Jane West-Eberhard in 2003.(10) This (1,10) accommodation can explain evolutionary change and scenario of phenotypic evolution posits that (1) a mutation or phenotypic novelty is a controversial issue among evolutionary environmental change triggers the expression of a novel, herit- biologists (for example Refs 11–16).
    [Show full text]
  • From So Simple a Beginning... the Expansion of Evolutionary Thought
    From So Simple A Beginning... The Expansion Of Evolutionary Thought #1 #2 From So Simple A Beginning... The Expansion Of Evolutionary Thought Compiled and Edited by T N C Vidya #3 All rights reserved. No parts of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior permission of the publisher. c Indian Academy of Sciences 2019 Reproduced from Resonance–journal of science education Published by Indian Academy of Sciences Production Team: Geetha Sugumaran, Pushpavathi R and Srimathi M Reformatted by : Sriranga Digital Software Technologies Private Limited, Srirangapatna. Printed at: Lotus Printers Pvt. Ltd., Bengaluru #4 Foreword The Masterclass series of eBooks brings together pedagogical articles on single broad top- ics taken from Resonance, the Journal of Science Education, that has been published monthly by the Indian Academy of Sciences since January 1996. Primarily directed at students and teachers at the undergraduate level, the journal has brought out a wide spectrum of articles in a range of scientific disciplines. Articles in the journal are written in a style that makes them accessible to readers from diverse backgrounds, and in addition, they provide a useful source of instruction that is not always available in textbooks. The sixth book in the series, ‘From So Simple A Beginning... The Expansion Of Evolu- tionary Thought’, is a collection of Resonance articles about scientists who made major con- tributions to the development of evolutionary biology, starting with Charles Darwin himself, collated and edited by Prof. T. N. C.
    [Show full text]
  • Degeneracy and Genetic Assimilation in RNA Evolution Reza Rezazadegan1* and Christian Reidys1,2
    Rezazadegan and Reidys BMC Bioinformatics (2018) 19:543 https://doi.org/10.1186/s12859-018-2497-3 RESEARCH ARTICLE Open Access Degeneracy and genetic assimilation in RNA evolution Reza Rezazadegan1* and Christian Reidys1,2 Abstract Background: The neutral theory of Motoo Kimura stipulates that evolution is mostly driven by neutral mutations. However adaptive pressure eventually leads to changes in phenotype that involve non-neutral mutations. The relation between neutrality and adaptation has been studied in the context of RNA before and here we further study transitional mutations in the context of degenerate (plastic) RNA sequences and genetic assimilation. We propose quasineutral mutations, i.e. mutations which preserve an element of the phenotype set, as minimal mutations and study their properties. We also propose a general probabilistic interpretation of genetic assimilation and specialize it to the Boltzmann ensemble of RNA sequences. Results: We show that degenerate sequences i.e. sequences with more than one structure at the MFE level have the highest evolvability among all sequences and are central to evolutionary innovation. Degenerate sequences also tend to cluster together in the sequence space. The selective pressure in an evolutionary simulation causes the population to move towards regions with more degenerate sequences, i.e. regions at the intersection of different neutral networks, and this causes the number of such sequences to increase well beyond the average percentage of degenerate sequences in the sequence space. We also observe that evolution by quasineutral mutations tends to conserve the number of base pairs in structures and thereby maintains structural integrity even in the presence of pressure to the contrary.
    [Show full text]
  • Soft Inheritance: Challenging the Modern Synthesis
    Genetics and Molecular Biology, 31, 2, 389-395 (2008) Copyright © 2008, Sociedade Brasileira de Genética. Printed in Brazil www.sbg.org.br Review Article Soft inheritance: Challenging the Modern Synthesis Eva Jablonka1 and Marion J. Lamb2 1The Cohn Institute for the History and Philosophy of Science and Ideas, Tel-Aviv University, Tel-Aviv, Israel. 211 Fernwood, Clarence Road, London, United Kingdom. Abstract This paper presents some of the recent challenges to the Modern Synthesis of evolutionary theory, which has domi- nated evolutionary thinking for the last sixty years. The focus of the paper is the challenge of soft inheritance - the idea that variations that arise during development can be inherited. There is ample evidence showing that phenotypic variations that are independent of variations in DNA sequence, and targeted DNA changes that are guided by epigenetic control systems, are important sources of hereditary variation, and hence can contribute to evolutionary changes. Furthermore, under certain conditions, the mechanisms underlying epigenetic inheritance can also lead to saltational changes that reorganize the epigenome. These discoveries are clearly incompatible with the tenets of the Modern Synthesis, which denied any significant role for Lamarckian and saltational processes. In view of the data that support soft inheritance, as well as other challenges to the Modern Synthesis, it is concluded that that synthesis no longer offers a satisfactory theoretical framework for evolutionary biology. Key words: epigenetic inheritance, hereditary variation, Lamarckism, macroevolution, microevolution. Received: March 18, 2008; Accepted: March 19, 2008. Introduction 1. Heredity occurs through the transmission of germ- There are winds of change in evolutionary biology, line genes.
    [Show full text]
  • Sociogenomics on the Wings of Social Insects Sainath Suryanarayanan
    HoST - Journal of History of Science and Technology Vol. 13, no. 2, December 2019, pp. 86-117 10.2478/host-2019-0014 SPECIAL ISSUE ANIMALS, SCIENCE AND TECHNOLOGY: MULTISPECIES HISTORIES OF SCIENTIFIC AND SOCIOTECHNICAL KNOWLEDGE-PRACTICES The Social Evolving: Sociogenomics on the Wings of Social Insects Sainath Suryanarayanan University of Wisconsin-Madison [email protected] Abstract: This paper excavates the epistemological and ontological foundations of a rapidly emerging field called sociogenomics in relation to the development of social insects as models of social behavior. Its center-stage is “the genome,” where social and environmental information and genetic variation interact to influence social behavior through dynamic shifts in gene expression across multiple bodies and time-scales. With the advent of whole-genome sequencing technology, comparative genomics, and computational tools for mining patterns of association across widely disparate datasets, social insects are being experimented with to identify genetic networks underlying autism, novelty-seeking and aggression evolutionarily shared with humans. Drawing on the writings of key social insect biologists, and historians and philosophers of science, I investigate how the historical development of social insect research on wasps, ants and bees shape central approaches in sociogenomics today, in particular, with regards to shifting understandings of “the individual” in relation to “the social.” Keywords: sociogenomics; social insect; sociobiology; postgenomics; biology and society © 2019 Sainath Suryanarayanan. This is an open access article licensed under the Creative Commons Attribution-NonCommercial-NoDerivs License (http://creativecommons.org/licenses/by-nc-nd/3.0/). Sainath Suryanarayanan 87 Introduction …I believe that the difficulty in studying the genetic basis of social behavior demands a bold, new initiative, which I call sociogenomics.
    [Show full text]
  • Dancing with DNA and Flirting with the Ghost of Lamarck
    Biology and Philosophy (2007) 22:439–451 Ó Springer 2006 DOI 10.1007/s10539-006-9034-x Book review Dancing with DNA and flirting with the ghost of Lamarck MARY JANE WEST-EBERHARD Smithsonian Tropical Research Institute, c/o Escuela de Biologı´a, Cı`udad Unı`versitaria, Costa Rica (e-mail: [email protected]; phone: +506-228-0001; fax: +506-228-0001) Review of: Evolution in Four Dimensions, Eva Jablonka and Marion J. Lamb, 2005, MIT Press, Cambridge, Massachusetts Evolution in Four Dimensions, by Eva Jablonka and Marion Lamb, is a dis- armingly good-humored book that challenges the overly gene-centered ‘Neo- Darwinian’ (mid-20th-Century-Synthesis) view of evolution via selection on phenotypes affected by random changes in DNA. Their remedy, more palat- able by the end of the book than I expected at the beginning, is to propose that we revise and expand our ‘‘unidimensional’ vision of heredity. Heredity, they argue, occurs in four dimensions: genetic inheritance, the conventionally rec- ognized mode of inheritance via transmission of DNA; epigenetic inheritance, or transmission of non-genetic information from parental cells to daughter cells, as in the cytoplasm of an egg; behavioral inheritance, or cultural trans- mission of learned traits; and symbolic transmission of information by means of abstract representation, especially language in humans. All four modes of inheritance provide variants on which natural selection can act. Therefore they portray evolution as occurring in four dimensions, corresponding to the four dimensions of inheritance. The style of the book makes it accessible to an educated lay reader. The text has been unburdened by removal of bibliographic citations to a single section of notes at the end of the book, and by a series of dialogues with a make-believe Devil’s advocate named Ifcha Mistabra (in Aramaic, ‘‘The opposite conjecture’’), where the authors anticipate and answer potential confusions and objections to their main points.
    [Show full text]
  • Genetic Assimilation: a Review of Its Potential Proximate Causes and Evolutionary Consequences
    Annals of Botany Page 1 of 11 doi:10.1093/aob/mcv130, available online at www.aob.oxfordjournals.org REVIEW: PART OF A SPECIAL ISSUE ON DEVELOPMENTAL ROBUSTNESS AND SPECIES DIVERSITY Genetic assimilation: a review of its potential proximate causes and evolutionary consequences Ian M. Ehrenreich1,* and David W. Pfennig2,* 1Molecular and Computational Biology Section, University of Southern California, Los Angeles, CA 90089, USA and 2Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA *For correspondence. E-mail [email protected] or [email protected] Downloaded from Received: 25 March 2015 Returned for revision: 7 May 2015 Accepted: 29 June 2015 Background Most, if not all, organisms possess the ability to alter their phenotype in direct response to changes in their environment, a phenomenon known as phenotypic plasticity. Selection can break this environmental sensi- tivity, however, and cause a formerly environmentally induced trait to evolve to become fixed through a process called genetic assimilation. Essentially, genetic assimilation can be viewed as the evolution of environmental http://aob.oxfordjournals.org/ robustness in what was formerly an environmentally sensitive trait. Because genetic assimilation has long been suggested to play a key role in the origins of phenotypic novelty and possibly even new species, identifying and characterizing the proximate mechanisms that underlie genetic assimilation may advance our basic understanding of how novel traits and species evolve. Scope This review begins by discussing how the evolution of phenotypic plasticity, followed by genetic assimila- tion, might promote the origins of new traits and possibly fuel speciation and adaptive radiation. The evidence implicating genetic assimilation in evolutionary innovation and diversification is then briefly considered.
    [Show full text]
  • Lamarckian Mechanisms As Developmental Bias and Their Darwinian Base – Descriptive Versus Explanatory Biology (Full Version) Andrzej Gecow [email protected]
    Lamarckian mechanisms as developmental bias… (full v.) A.Gecow [email protected] Sep. 29, 2020 1 Lamarckian mechanisms as developmental bias and their Darwinian base – descriptive versus explanatory biology (full version) Andrzej Gecow [email protected] Abstract The article points out the main obstacles in the discussion of Lamarckian mechanisms, resulting from overly persisted beliefs, habits and understatement. The aim of the article is not to show new biological observation, but to indicate the need to change methodology. ‘Lamarckian mechanisms’ are those that create ‘non-random’ changes (in the aspect of adaptation), and even ‘resulting from instruction’, and these changes become evolutionary. It is part of ‘developmental biases’. To avoid widespread prejudices a permanent stress is needed that such ‘Lamarckian mechanisms’ are an effect of Darwinian mechanisms but this stress is not enough visible. The term ‘Lamarckism’ has two meanings unreasonably connected. The correct meaning is, that adaptive evolutionary changes can be induced by environment and next they are inherited, but typically it is understood as irrational believing that evolutionary changes are adaptive without necessity of help of Darwinian mechanisms. In this case the terms ‘Lamarckian mechanisms’ and ‘Lamarckism’ are not coherent which leads to misunderstanding. Such irrational Lamarckism has small base in Lamarck’s view, it arisen from too shallow interpretation of Lamarck. In the theme ‘inheritance of acquired characters’ a few steps to evolutionary change is indicated, which typically are omitted in the description. Old such descriptions need rebuilding in a new coherent system of notions but to create such system a theory is necessary. The Lamarckian dimension of evolution protrudes beyond the basics of Modern Synthesis however necessity to change the name of the synthesis to Extended Evolutionary Synthesis is discretionary decision.
    [Show full text]
  • Can Heritable Epigenetic Variation Aid Speciation?
    Hindawi Publishing Corporation Genetics Research International Volume 2012, Article ID 698421, 9 pages doi:10.1155/2012/698421 Review Article Environmental Heterogeneity and Phenotypic Divergence: Can Heritable Epigenetic Variation Aid Speciation? Ruth Flatscher,1, 2 Bozoˇ Frajman,1 Peter Schonswetter,¨ 1 and Ovidiu Paun2 1 Institute of Botany, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria 2 Department of Systematic and Evolutionary Botany, University of Vienna, Rennweg 14, 1030 Vienna, Austria Correspondence should be addressed to Ovidiu Paun, [email protected] Received 22 August 2011; Revised 7 November 2011; Accepted 23 November 2011 Academic Editor: Christina L. Richards Copyright © 2012 Ruth Flatscher et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The dualism of genetic predisposition and environmental influences, their interactions, and respective roles in shaping the phenotype have been a hot topic in biological sciences for more than two centuries. Heritable epigenetic variation mediates between relatively slowly accumulating mutations in the DNA sequence and ephemeral adaptive responses to stress, thereby providing mechanisms for achieving stable, but potentially rapidly evolving phenotypic diversity as a response to environmental stimuli. This suggests that heritable epigenetic signals can play an important role in evolutionary
    [Show full text]
  • Evolution in Four Dimensions by Eva Jablonka and Marion J. Lamb
    Book Review Evolution in Four Dimensions jecture’’) and the authors. The final chapter contains a ‘‘last Eva Jablonka and Marion J. Lamb. dialogue’’ that helps to review, flesh out, and extend ques­ tions that had or had not been presented by Ifcha in previous MIT Press, Cambridge, MA, 2005. chapters. Copious endnotes, containing the more specialized The basic claim of Jablonka and Lamb is that ‘‘biological information, are organized on a page-by-page basis at the end thinking about heredity and evolution is undergoing a revo­ of the book. An extensive bibliography occupies pages 417– lutionary change. What is emerging is a new synthesis which 446, followed by a well-documented index. Quaint drawings challenges the gene-centered version of neo-Darwinism that are peppered throughout the text to help the reader visualize has dominated biological thought for the last fifty years.’’ the concepts presented therein. They argue in the Prologue that Natural selection requires heritable sources of phenotypic variation to be effective. The most commonly known source � there is more to heredity than genes; of phenotypic variation is the genetically based differences � some hereditary variations are nonrandom in origin; between organisms in a population. The first three chapters � some acquired information is inherited; and review how Darwinism has been transformed by new discov­ � evolutionary change can result from instruction as well as eries, especially those emanating from molecular biology and selection. developmental biology. In addition to gene mutations, this The subtitle of the book is Genetic, Epigenetic, Behavioral, section outlines three additional sources of heritable diversity and Symbolic Variation in the History of Life;thus, thefour produced through sexual reproduction: (1) offspring receive dimensions of the title.
    [Show full text]