On Human Nature. Biology, Psychology, Ethics, Politics, and Religion

763 Pages·2016·32.699 MB·English

by  Michel Tibayrenc, Francisco J. Ayala

On Human Nature
Biology, Psychology, Ethics,
Politics, and Religion
Edited by
Michel Tibayrenc
Institut de Recherche pour le De´veloppement,
Montpellier, France
Francisco J. Ayala
Department of Ecology and Evolutionary Biology,
Ayala School of Biological Sciences,
University of California, Irvine, CA, United States
AMSTERDAM lBOSTON lHEIDELBERGlLONDON lNEWYORK lOXFORD lPARIS
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List of Contributors
J. Alcock Arizona State University, Tempe, AZ, United B. Dubreuil Québec (Québec), Canada
States
M.W.FeldmanStanfordUniversity,Stanford,CA,United
K. Aoki Meiji University, Tokyo, Japan States
G. Arunkumar SASTRA University, Thanjavur, India C.E. Finch University of Southern California, Los
Angeles, CA, United States
S.N. Austad University of Alabama at Birmingham,
Birmingham, AL, United States M.V.FlinnUniversityofMissouri,Columbia,MO,United
States
F.J. Ayala University of California, Irvine, CA, United
States M.FumagalliUniversityCollegeLondon,London,United
Kingdom
D.H. Bailey University of California, Irvine, CA, United
States P. Gagneux University of California at San Diego, La
Jolla, CA, United States
F. Balloux University College London, London, United
Kingdom S. Gaudieri University of Western Australia, Nedlands,
WA, Australia; Vanderbilt University, Nashville, TN,
O.Bar-YosefHarvardUniversity,Cambridge,MA,United
United States; Murdoch University, Murdoch, WA,
States
Australia
H.C. Barrett UCLA, Los Angeles, CA, United States
L.F. Greer University of California, Irvine, CA, United
W.M.BaumUniversityofNewHampshire,Durham,NH,
States
United States; University of California, Davis, CA,
S. Hameroff The University of Arizona, Tucson, AZ,
United States
United States
A. Bilbao Leis University of Heidelberg, Mannheim,
M. Henneberg TheUniversity ofAdelaide, Adelaide,SA,
Germany
Australia
T. Borchert University of Vermont, Burlington, VT,
A.K. Hill University of Washington, Seattle, WA, United
United States
States
E.BoyleGeorgeWashingtonUniversity,Washington,DC,
M. John Murdoch University, Murdoch, WA, Australia
United States
A. Kingstone University of British Columbia, Vancouver,
L.G. Cabral University of California, Irvine, CA, United
BC, Canada
States
A.L. Canfield University of Chicago, Chicago, IL, United M. Kronfeldner Central European University, Budapest,
Hungary
States
K.E.W. Laidlaw University of British Columbia,
C.J.Cela-CondeUniversityoftheBalearicIslands,Palma
Vancouver, BC, Canada
de Mallorca, Spain
D. Lordkipanidze Georgian National Museum, Tbilisi,
B.G. Cervantes University of California, Irvine, CA,
Georgia
United States
S. Mallal Vanderbilt University School of Medicine,
T.W. Deacon University of California, Berkeley, CA,
Nashville, TN, United States; Murdoch University,
United States
Murdoch, Western Australia
J. DeGregori University of Colorado School of Medicine,
R. McDermott Brown University, Providence, RI, United
Aurora, CO, United States
States
xvii
xviii List of Contributors
K. McKenzie University of Toronto, Toronto, ON, A.I. Rozhok University of Colorado School of Medicine,
Canada; Center for Addiction and Mental Health, Aurora, CO, United States
Toronto, ON, Canada; CEO Wellesley Institute,
F. Rühli Institute of Evolutionary Medicine, University of
Toronto, ON, Canada
Zürich, Zürich, Switzerland
K.R. Monroe University of California, Irvine, CA, United
M. Ruse Florida State University, Tallahassee, FL, United
States
States
J. Murphy Ulster University, Derry, Northern Ireland
G.A.RutledgeUniversityofCalifornia,Irvine,CA,United
E.NasiopoulosUniversityofBritishColumbia,Vancouver, States
BC, Canada
M. Stoneking Max Planck Institute for Evolutionary
B. Oakley Oakland University, Rochester, MI, United Anthropology, Leipzig, Germany
States
A.R. Templeton Washington University, St. Louis, MO,
T. Peters GTU/CTNS, Berkeley, CA, United States United States; University of Haifa, Haifa, Israel
R.M. Pitchappan Chettinad Academy of Research & M. Tibayrenc Maladies Infectieuses et Vecteurs
Education, Chennai, India Ecologie,Génétique,EvolutionetContrôle,MIVEGEC
(IRD 224-CNRS 5290-UM1-UM2), IRD Center,
T.M.PreussEmoryUniversity,Atlanta,GA,UnitedStates
Montpellier, Cedex 5, France
D.A. Puts The Pennsylvania State University, University
A. Varki University of California at San Diego, La Jolla,
Park, PA, United States
CA, United States
M. Reimers Michigan State University, East Lansing, MI,
G.M. Verschuuren Genesis P.C., LLC, Atkinson, NH,
United States
United States
E.F.RiskoUniversityofWaterloo,Waterloo,ON,Canada
J.Y. Wakano Meiji University, Tokyo, Japan
A. Roland National Psychological Association for
B. Wood George Washington University, Washington,
Psychoanalysis, New York, NY, United States
DC, United States
M.R. Rose University of California, Irvine, CA, United
F. Zampieri University of Padua, Padua, Italy
States
J.RoughgardenTheHawai’iInstituteofMarineBiology,
Kane’ohe, HI, United States; Stanford University,
Stanford, CA, United States
Editors’ Biographies
MichelTibayrenc,MD,PhD,hasworkedontheevolution
of infectious diseases for more than 35years. He is a
director of research emeritus at the French Institut de
Recherche pour le Développement (IRD), the founder and
editor-in-chief of Infection, Genetics and Evolution (Elsev-
ier),witha2014impactfactorof3.015,andthefounderand
principalorganizeroftheinternationalcongressesMEEGID
(molecular epidemiology and evolutionary genetics of
infectious diseases). He is the author of more than 200
internationalpapers.HehasworkedforoneyearinAlgeria
(as a general practitioner), oneyear in French Guiana,
sevenyears in Bolivia, fiveyears in the United States, and
threeyearsinThailand.Hehasbeentheheadoftheunitof
research “genetics and evolution of infectious diseases” at
theIRDresearchcenterinMontpellier,France,for20years.
With his collaborator Jenny Telleria, he is the founder and
scientificadviseroftheBolivianSocietyofHumanGenetics
(2012). He has won the prize of the Belgian Society of
tropicalmedicine(1985),themedaloftheInstitutoOswaldo
Cruz, Rio de Janeiro (2000), for his work on Chagas
disease,andheisa fellowoftheAmerican Associationfor
the Advancement of Science (1993).
Francisco J. Ayala is University Professor and Donald
Bren Professor of Biological Sciences and Professor of
Philosophy attheUniversityofCalifornia,Irvine.OnJune
12,2002,PresidentGeorgeW.Bushawardedhimthe2001
NationalMedalofScienceattheWhiteHouse.OnMay5,
2010,hereceivedthe2010TempletonPrizeforexceptional
contribution to affirming life’s spiritual dimension from
HRH Prince Philip, Duke of Edinburgh, at a private cere-
mony in Buckingham Palace, London.
BorninMadrid,Spain,hehaslivedintheUnitedStates
since 1961, and became a US citizen in 1971. He has
published more than 1100 articles and is the author or
editor of 50 books, including Essential Readings in
EvolutionaryBiology(2014),TheBigQuestions:Evolution
(2012), Am Ia Monkey? (2010),Human Evolution (2007),
and Darwin’s Gift to Science and Religion (2007).
He is a member of the U.S. National Academy of
Sciences,theAmericanAcademyofArtsandSciences,and
the American Philosophical Society, a Fellow of the
Linnean Society of London, Foreign Member of the
xix
xx Editors’ Biographies
Russian Academy of Sciences, the Royal Academy of Gold Medal of the Stazione Zoologica of Naples, the
Sciences of Spain, the Accademia Nazionale dei Lincei President’s Award of the American Institute of Biological
(Italy), the Mexican Academy of Sciences, and other Sciences, the Scientific Freedom and Responsibility
international academies. Award from the AAAS, the Medal of the College of
Ayala has received the Gold Honorary Gregor Mendel France, and numerous other recognitions and awards. He
Medal from the Czech Academy of Sciences, the Gold hasalsoreceivedhonorarydegreesfrom24universitiesin
Medal of the Accademia Nazionale dei Lincei, the 10 countries.
Foreword
Science has evolved through the centuries by the entan- One result is the production of ever farther-reaching syn-
glement of two very different modes of creative inquiry. theses such as the one presented in this book, which dares
The first mode is the straightforward discovery of new to take biology deeper into the humanities, and the hu-
phenomena, typically made more likely by technological manities deeper into biology.
advance. For example, researchers are now able to deter- The contribution of the present work, On Human Na-
mine the age of most fossil and archaeological remains by ture:Biology,Psychology,Ethics,Politics,andReligion,is
the amount of radioactive decay measured within them. potentiallyprofound.Itisencyclopedicincoverage,written
Theycantracklocalbrainactivitywithfunctionalmagnetic by leaders in a large part of human biology rarely covered
resonance imaging. By shifting to frequencies higher than withinasinglevolume.Itsaim,according totheeditors,is
visiblelightontheelectromagneticspectrum,theyareable to evaluate “the present state of knowledge on human di-
tofindandstudymicroorganismstoosmalltobeseenwith versity and its adaptive significance through a broad se-
conventional light microscopy. And by discovering lection of representative chapters.” Its center is the
“missing link” species by whatever means, the researchers crossroads between biology and the human sciences.
candrawmoreaccurate,andoften surprising,evolutionary OnHumanNatureusesdetailedinformationtodisclose
family trees. howandwhenhumanityoriginated,whatwearetoday,and
Thesecondmodeofinquiryisthesynthesisofnewand why we behave the way we do in an increasingly fragile
old information across disciplines. Soon after the structure worldofourownmaking.Thecontentisfearless, tracking
of DNA was adduced, its base-pair code was broken, then change not just through the dawn of history in Neolithic
linked to the already well-established principles of partic- times, but much deeper into Paleolithic times, when our
ulateheredity.Thereensuedalinkagetothemotherlodeof physiological and emotional responses were programmed
established biochemistry and cell architecture. A major by genetic evolution.
consequence was the inauguration of molecular biology, From the same perspective it is entirely appropriate for
whoseachievementssufficetodesignatethesecondhalfof someoftheauthorsinthesymposium,aselsewhereamong
the 20th century as the golden age of modern biology. many scholars, to carry biological reasoning into subjects
As the veils of mystery in biology have been removed traditionally reserved for the humanities. It has become
one by one, the cause-and-effect explanations have drawn increasingly evidentdalthough far from conclusively
closer together. Hybrid disciplines became the rule in provendthatthebiologicalsciencesarenotseparatedfrom
biology, yielding, for example, behavioral ecology, physi- humanistic explanations of aestheticsandmoral reasoning,
ological ecology, biochemical physics, developmental at least not by the divide of seismic proportions formerly
biology, economic botany, neurobiology, population ge- accepted.Likeothertraitsofphysiologyandbehavior,they
netics, sociobiology, and a thicket of others, each attended are guided by emotional responses programmed from the
by its own journals and well-trained experts. start by genetic evolution. “Human nature” is a concept
At first thought this proliferation of specialties may appropriately applied to characterize traits of this bedrock
seem a symptom of the splintering of biological knowl- origin. Biological research is the truest way to track its
edge. But the opposite is true. The hybrid disciplines are influence, or lack of influence, during the evolutionary
better recognized as silos that researchers have built to transition from instinct to culture.
masterdetailedinformationandtherebytopromoteoriginal
Edward O. Wilson
discoveries. When biology is viewed as a whole, the
principles, the fundamentals, and even the styles of Museum of Comparative Zoology,
expression are seen as actually convergent. The overall Harvard University,
networkofbiologicalknowledgeitexpressesistightening. Cambridge, MA, United States
xxi
Preface
The late Nobel Prize winner Jacques Monod used to say The editors decidedthateachauthor woulddeliverher/
that the ultimate goal of science was to elucidate Human hischapterindependentlyfromotherauthors.Authorswere
Nature. Monod, a molecular biologist, had written the awareaboutthewholedesignandcontentofthebook,and
famous book Chance and Necessity, which expressed a oftheidentityofotherauthors.However,theydidnotread
striking neodarwinian, reductionist, and atheist view of the the other chapters of the book. Authors were only given a
living world. The properties of the genetic code, recently few basic indications about the concept of the book.
discovered at that time (the book was published in 1970) Chapterswerereviewedbytheeditorsonly,whointerfered
appearedtoMonodasevidencethatabsolutechancewasat aslittleaspossiblewiththefinaloutcome.Thegoalofthis
the root of evolution. It was not a hypothesis: it was a way of processing was to get the personal vision of each
certainty. For the author, blind natural selection (“Neces- authorabouther/hisownfield.Thewholedesignandsetof
sity”) was able to fully explain teleonomy (the obvious chapters has been extensively discussed between the two
purposefulness of living organisms’ features). editors,aswellastheselectionofauthors.Thetopicswere
We now know much more genetics and biology than selected before identifying authors. Once a topic was
Monod did. However, to the eyes of many, genetics and agreed on between the two editors, top authors were
evolutionary studies are far from being able to provide a selected either from personal contacts or through relevant
comprehensive and sophisticated view of human nature. databases.Theselectionoftopicsisareflectionofhowthe
These studies only bring some important parts of the puz- editors conceive what should not be a full synthesis about
zle,whilemany questionsremainunanswered.Thisisalso humannaturebutratheradiversifiedsampleofhowhuman
the thinking of the two editors and initiators of this book. intelligence approaches various facets of human nature.
This is why, when designing the project, we decided to Selection of topics and authors certainly is not beyond
coverasbroadarangeaspossibleofallfieldsofknowledge criticism. Moreover, the two editors are both Westerners
that would enlighten human nature. Controversies are and trained in the tradition of modern biology. A book on
neither avoided nor hidden. However, subjects that, in the human nature designed by Thai Buddhist monks or
view of the editorsdrightly or wrongly asserting their Amazonian forest native shamans would certainly have
decisionddo not meet the requirements of methodological been quite differentdand fascinating. Cultural and pro-
rigor (such as creationism and intelligent design) were not fessionalbiasesaswellasethnocentrismaresinssharedby
included in the project. Otherwise, the book presents a fair everyone on Earth. Nevertheless, the design of the book
balance between social, medical, and biological sciences. should be considered to be free of any deliberate bias or
Authors were asked to make their chapters accessible to a thematic imperialism.
broadrangeofreaders,includingstudents,teachers,andthe
educatedpublic.However,allchaptersarequiteuptodate Michel Tibayrenc
andincludeallrecentadvancesintheirfield,whichshould Francisco J. Ayala
make them highly relevant to specialists as well.
The book comprises three parts, intended to be com-
plementary to each other and purposely featuring some
overlap and redundancy:
Part I: Biological Basis of Human Diversity
Part II: Psychology, Behavior and Society
Part III: Ethics, Politics and Religious Considerations
xxiii
Chapter 1
The Advent of Biological Evolution and
Humankind: Chance or Necessity?
C.J. Cela-Conde1 and F.J. Ayala2
1UniversityoftheBalearicIslands,PalmadeMallorca,Spain;2UniversityofCalifornia,Irvine,CA,UnitedStates
CHANCE AND NECESSITY considereddecisiveinthehigherorganisms,whosesurvival
and reproduction depend above all upon their behavior.”
Chance and Necessity is the title of a book written by
(Monod, 1971, p. 121).
Jacques Monod which explains how DNA is expressed in The necessity expressed by the organism’s purposes
the enzymes and proteins determining the organism’s
may seem to lead us to a Lamarckian-like scheme. How-
phenotype. Monod holds that “[t]he initial elementary ever, “teleonomy” and “purpose” are related, in Monod’s
events which open the way to evolution in the intensely
analysisofthewholeprocessofevolution,totheresultsof
conservative systems called living beings are microscopic, everyorganism’sfightforsurvivalandreproduction.Atrue
fortuitous, and totally unrelated to whatever may be their
Lamarckianschemeshouldrelatetheteleonomicpurposeto
effectsuponteleonomicfunctioning”(Monod,1970,1971, the reproduction, ie, transmission of the organism’s
p.114).Morethanfourdecadeslater,wekeepinmindthe achievements in its fight for survival. Is this the case?
same view: evolution starts fortuitously, and unrelated to Monod’s work is an example of an anti-Lamarckian
effects or events. These microscopic events mean “nov-
interpretation of the links existing between proteins and
elties”that,asMonodsaid,“intheshapeofanalterationof nucleic acids. With his own words “there is no possible
the protein structure, will be tested before all else for its (Monod’semphasis)mechanismwherebythestructureand
compatibility with the whole of the system already bound performance of a protein could be modified, and these
by the innumerable controls commanding the execution of modificationstransmittedevenpartiallytoposterity,except
theorganism’sprojectivepurpose”(Monod,1971,p.115).
analterationoftheinstructionsrepresentedbyasegmentof
The word “purpose” obviously is polysemic, meaning DNA sequence” (Monod, 1971, p. 107e108).
desires, ends, goals, determinations, resoluteness, and de-
However, the lack of a mechanism for transmitting
signs, but also meaning practical results. The teleonomic protein modifications to the DNA does not preclude the
functioning that is affected by the initial, fortuitous events
existenceofotherkindofhereditylinkednottothegenetic
could be explained in any of these several levels of “pur-
material but to its development. This is the case of epige-
pose.”Environmentalsocounts:“Letussaythatthe‘initial
netic processes.
conditions’ of selection encountered by a new mutation
simultaneously and inseparably include both the environ- EPIGENETIC PROCESSES
ment surrounding it and the total structures and perfor-
mances of the teleonomic apparatus belonging to it.” We will take epigenetics as the “DNA sequence-
(Monod, 1971, p. 121). In the end, “It is obvious that the independent changes in chromosomal function that yield
partplayedbyteleonomicperformancesintheorientationof a stable and heritable phenotype” (Rissman and Adli,
selection becomes greater and greater, the higher the level 2014). Thephenotype may refer tothewhole organism, or
of organization and hence autonomy (Monod’s emphasis) toonlyparticularcellsortissues.Threeconditionsmustbe
of the organism with respect to its environmentdto the fulfilled for an epigenetic process, currently called trans-
point where teleonomic performance may indeed be generational epigenetic inheritance (TEI): (1) changes in
3
OnHumanNature.http://dx.doi.org/10.1016/B978-0-12-420190-3.00001-6
Copyright©2017ElsevierInc.Allrightsreserved.
4 PART | I BiologicalBasisofHumanDiversity
chromosomal function expressed in a different phenotype information appearing by means of well-known molecular
(different from parents’ phenotype); (2) independent from mechanisms. All TEI phenotypes are the result of genetic,
DNAsequences(neithercodedinthegenome,norlinkedto inheritablematerialthat,underexternaldenvironmental,at
parents’ germ cells alterationsdsee Choi and Mango, least relative to the cell or tissuedpressures, becomes
2014);(3)whichisheritable inastable way(persistingfor modified. TEI phenotypes are inherited because parents
at least three generations). As Choi and Mango say, “Both transmitnotonlyDNAtotheprogenybutalsobecausethe
invertebratesandvertebratesexhibitsuchinheritance,anda mother contributes with a whole set of cellular organs, as
range of environmental factors can act as a trigger.” The well as several kinds of ncRNA, included in the ovule.
challenge is to ascertain “what molecular mechanisms ac- Thischapterwillengagethesetwocomponents,hazard
count for inheritance of TEI phenotypes” (Choi and and necessity, of human evolution, exploring how they
Mango, 2014). participateandbecomeintegratedinthehumanphylogeny.
Mechanisms leading to TEI have been related to (see
Rissman and Adli, 2014): WHAT IS A HOMININ?
l DNA methylation (a biochemical process in which
We humans form an evolutionary lineage among those
methylchemicalgroupsarecovalentlyattachedtocyto-
belongingtotheorderPrimata.Accordingtothetraditional
sine residues by DNA methyltransferase enzymes); classification, the order Primata includes three suborders
l histonemodifications(posttranslationalmodificationsin
(Anthropoidea, Tarsioidea, and Prosimii). The suborder
histone proteins, mainly studied in organisms, such as
Anthropoideaincludestwoinfraorders,Catarrhini(African,
Caenorhabditis elegans, lacking DNA methylation);
European, and Asian monkeys) and Platyrrhini (American
l ncRNAs (noncoding RNA that alters chromatin struc-
monkeys), which diverged after continental drift separated
ture and DNA accessibility).
SouthAmericafromAfrica.Catarrhiniaredividedintotwo
Theneedforthesemechanismsseemsclear.Thoughall superfamilies:Cercopithecoidea(OldWorldmonkeys)and
cells share a common nuclear genome, the necessity for Hominoidea (apes and humans; hominoids in popular
genetic expression, from DNA to proteins, varies in the terms; see Table 1.1).
different tissues. Thus, a great part of the genome must be In the 1960s, with analyses of proteins in the blood
silenced,notleadingtocodifyanyproteinorenzyme.This serum of hominoids, Morris Goodman, a molecular
silencing strategy is reached during the ontogenetic devel- geneticistatWayneStateUniversityinDetroit,determined
opment, ie, by means of epigenetic episodes. Several fac- that humans, chimpanzees, and gorillas are closer to each
tors, including environmental conditions and parental care, other than any of them is to orangutans (Goodman, 1962,
seem to affect epigenetics. If the alterations provoked are 1963; Goodman et al., 1960). According to Goodman’s
inherited, we are facing a TEI phenotype. results the evolution of hominoids proceeded very differ-
Chance has a great role in the phylogenetic appearance entlyfromwhatSimpson’staxonomyimplied.Thelineage
of any new organism. As we know, paleontology is a his- leadingtoorangutanswasthefirsttosplit,thenthelineage
torical science: it does not consist of predictive laws. of gorillas split from the others, and, finally, the chimpan-
Rather, it describes the evolutionary changes that occurred zees and human lineages diverged from each other.
in evolution. These changes include processes such as Consequently, using the language of cladistics, lineages of
mutation, genetic recombination ensuing from sexual humans and chimpanzees are “sister groups.” They come
reproduction,andepigeneticeventspromptedbyparticular from a common ancestor and thus share remarkable simi-
environmental circumstances. What about necessity? It is larities.Regardingtheageofthesplitofthesesistergroups,
imposed by the environmental circumstances associated Vince Sarich and Alan Wilson (1967a,b) argued that the
with each evolutionary episode. Every population of or- rateofgeneticchangeinchimpanzeesandhumanswasfast,
ganisms must remain adapted to the demands of its and estimated that the divergence of the evolutionary
ecosystem or it will lose its biological fitness. branches of the last two hominoid lineages took place
Epigenetic processes become a kind of intermediate 4e5Ma (mega-annum, million years) ago.
expanse between absolute chancedthe fortuitous modifi- Here we will adopt a taxonomic classification which
cation of DNAdand required necessitydthe suitability of respectstheincreasingmolecularevidence.Wewilllargely
new proteins to adapt to environment. Epigenetics have follow Bernard Wood and Brian Richmond (2000;
been used sometimes as an argument against the neo- Table1.1).ThefamilyHominidaeembracesthesetofgreat
Darwinist approach to evolution. The fact that noncoding apes and humans. Orangutans constitute the subfamily
changes could be inherited has been claimed as something Ponginae and gorillas the subfamily Gorillinae, while
like a Lamarckian approach. However, no mysterious chimpanzees and humans form the subfamily Homininae.
process that might be achieved by an organism’s alleged Within the latter, chimpanzees belong to the tribe Panini
“will”exists.DNAsilencingobviouslydependsongenetic and humans to the tribe Hominini. The human lineage has