Toward a Natural History of Team Sports
Toward a Natural History of Team Sports
Kevin M. Kniffin 0 1
Michelle Scalise Sugiyama 0 1
Why Play in Teams? 0 1
0 S. C. Johnson College of Business, Dyson School of Applied Economics and Management, Cornell University , Ithaca, NY 14853 , USA
1 University of Oregon , Eugene, OR , USA
Team sports; Team play; Play fighting; eSports
Play and play fighting are human universals
, and certain types of
play appear to recur across human cultures regardless of social or technological
(Cooper 1949; Culin 1907; Murdock 1945)
. Despite this, little attention
has been paid to the question of whether these behaviors are adaptations or by-products.
Do these behaviors develop spontaneously, or are they learned? Do they exhibit
evidence of design and function, or do they emerge from the operation of physical
and psychological structures that evolved for other purposes? The articles in this special
issue of Human Nature are dedicated to piquing curiosity about and stimulating
research on these questions.
One clue to the nature of play is its ubiquity: play (including play fighting) occurs
across a broad range of taxa, suggesting that it is a deep part of our zoological heritage.
Thus, one potentially fruitful line of inquiry is cross-species comparison, which can be
used to tease out those aspects of play behavior that are unique to humans and those
that we share with other species. On this point, it has been noted that play tends to occur
in endothermic vertebrate species that exhibit postnatal parental care
(Bekoff and Byers
1998; Ficken 1977)
and tends to occur largely?although by no means exclusively
(Cordoni 2009; Logan and Longino 2013; Pellis and Iwaniuk 1999)
juvenile period (Fagen 1981). These patterns suggest a relationship between play and
ontogeny and inform the view in ethology that play is an adaptation that develops,
rehearses, and/or fine-tunes skills that provide fitness benefits later in the individual?s
(Fagen 1974, 1981)
. Others have noted that play provides opportunities for
comparative self-assessment, enabling individuals to track their progress toward
mastery of a given skill and their proficiency relative to that of their fellows (e.g.,
Thompson 1998). Onlookers, too, may assess the absolute and relative proficiency of
(e.g., Apostolou 2015; Apostolou and Zacharia 2015)
. The evaluative
opportunities presented by play may explain its persistence into adulthood, especially among
long-lived species that form cooperative alliances and/or exhibit dominance hierarchies.
One apparently unique feature of human play is play in teams. In nonhuman species,
play behavior is overwhelmingly dyadic. Even in gregarious taxa, group play appears
to be rare. When it does occur
(e.g., in bonobos; Behncke 2016)
, it tends to be polyadic
rather than coalitional: although several individuals may participate, their interactions
are one-on-one rather than group-on-group. With the possible exception of dolphins
(Scalise Sugiyama et al. 2018)
, humans are the only species known to play in teams
. Moreover, there are hints that this behavior is species-typical:
research indicates that team sports are pervasive across forager
(Scalise Sugiyama et al.
(Deaner and Smith 2013)
societies, suggesting that team play
is scaffolded by powerful motivational architecture.
Humans also appear to be the only species that play-fights in teams. Although
definitions of combative play vary somewhat
(Deaner and Smith 2013; Sipes 1973)
similarities between sports and fighting have long been noted
(e.g., Fenichel and
Rangell 1995; Lorenz 1966; Murdock 1949; Tiger 1970)
. As with play in general,
dyadic play fighting is common across a wide range of species
(Boulton and Smith
, but team play fighting is not, raising the question of why this particular form of
team play is so widespread across human groups. Another striking feature of combative
team play is the powerful emotional responses it evokes in non-participants. Human
interest in team contact sports goes well beyond a desire to participate: humans also
exhibit (i) a keen interest in watching teams play (spectatorship), (ii) a predilection for
(e.g., sports statistics, fantasy football, schoolyard picking; see Barbaro et al.
(e.g., trash-talking; Kniffin and Palacio 2018)
skills of players, (iii) strong and public preferences
(e.g., loyalties; Kruger et al. 2018)
for certain teams over others, and (iv) pronounced emotional and physiological
responses to perceived officiating bias
(e.g., Alvarado et al. 2018)
Whence the motivation for these behaviors? This question is a challenging one
because combative team play is a hybrid that combines motor play, strategic play, and
social play (i.e., play in which individuals interact with each other). Combative team
play requires that individuals coordinate their actions with their team members in ways
that are calculated to outmaneuver the opposing team, which in turn requires
anticipating the actions of opponents. This complex activity may thus engage psychological
structures associated with cooperation, planning, theory of mind, and
in-group/outgroup bias, among others. These components of combative team play are a logical
starting point for questions regarding design and function. For example, are the
cooperative challenges involved in team play fighting specific to this activity or are
they typical of cooperation in general? Is the strategic planning deployed in combative
team play applicable only in this context, or is it generalizable to other spheres of
human endeavor? As these questions suggest, the study of combative team play may
shed new light not only on play behavior but on the psychological phenomena involved
in its production.
We believe that team contact play merits more attention from evolutionary social
scientists and biologists. The present volume directs attention to some of the distinctive
aspects of this behavior and encourages future research aimed at a more nuanced and
holistic understanding of this zoologically unusual phenomenon. For example, the
common use of language such as ?combative sports?
(Deaner and Smith 2013:8)
in the play literature implies recognition of an
affinity between contact sports and warfare. This raises questions about the nature of
this relationship?i.e., the behavioral and contextual cues evoked by team contact play
that invite a comparison with combat, explored herein by Scalise Sugiyama et al.
(2018). Parallels between contact sports and combat may also be relevant to
understanding other findings reported in this issue, such as the hormonal profiles associated
with team sports participation and spectatorship
(Alvarado et al. 2018; McHale et al.
, preferences for more-proficient players as coalition members in combat
(Barbaro et al. 2018), and increased self-perceived mate value following victory in a
(Longman et al. 2018)
. Another parallel is suggested by the
observation that value systems related to war and sports ?tend to overlap and support
each other?s presence?
. This line of inquiry is developed in Pollack
et al.?s (2018) study of belief in supernatural assistance and its influence on combat
outcomes, as simulated through team contact play. Other contributions explore
nonphysical avenues and expressions of competition in sports, such as the use of ?trash
talk? to denigrate opponents
(Kniffin and Palacio 2018)
and the related phenomena of
team rivalry and fan loyalty
(Kruger et al. 2018)
(with the exception of
Scalise Sugiyama et al. 2018)
the studies in this issue focus on sports played in modern
nation-states, their findings invite us to imagine the challenges and opportunities
presented by ancestral human environments that have resulted in the development
and persistence of team contact play across human societies.
Sports Teams as Organizational Laboratories
This issue also calls attention to the value of using sports as a model domain for
studying evolutionary dynamics within and among teams. The contributions herein
point to a range of theoretical questions that can be profitably explored and tested
through the use of sports teams and related phenomena (e.g., spectatorship, intergroup
rivalries, virtual sports), as well as methodological innovations that are increasingly
showcased by the study of sports. The high number, diversity, and accessibility of
sports teams?as organizations unto themselves?offers a tremendous opportunity for
researchers interested in exploring how organizations work.
To date, sexual selection theory has been central to research on motivational
factors underlying sports participation and spectatorship. For example, using a
sample of male professional tennis players,
Farrelly and Nettle (2007)
prediction that if men are ultimately motivated
to succeed in sports
for the benefit of reproductive success, then marriage will tend to be associated
with a reduction in performance. Other research informed by this theoretical
perspective suggests that the substantially higher variance in reproductive fitness
available to men compared with women helps account for apparently higher
levels of male competitiveness, often manifested in the domain of team sports
(e.g., Apostolou and Lambrianou 2017; Balish et al. 2016; Deaner et al. 2012,
. Recent work replicates the overall between-sex difference in between-sex
competition but otherwise finds that women do tend to be as competitive as men
when competing against themselves
(Apicella et al. 2017)
. The increasing trend
toward coed sports competitions
(e.g., curling in the 2018 Winter Olympics had
a new mixed-gender competition [Costa 2018])
adds further dimensions to
explore using this theoretical framework.
Team sports also provide an arena for testing multilevel selection theory. For
Kniffin and Wilson (2005
, 2010) showcase this theory in relation to a field
study of rowing teams. Owing to the nature and rules of the sport, rowers exhibit
phenotypic uniformity with each other; consequently, they meet one of the primary
criteria needed for variation-and-selective-retention to occur at the organizational level
(as specified by Wilson and Sober 1994)
examined rowers in
support of his reductionist approach wherein team-level performance is universally
recognized as epiphenomenal artifacts of individual pursuits. Although the
levels-ofselection debate is prone to seemingly endless definitional arguments
(e.g., Wilson and
, team sports offer concrete opportunities for theory development and
hypothesis testing in relation to understanding the ways in which individuals interact
For application of both sexual and multilevel selection theoretical frameworks, team
sports provide dynamic ?organizational laboratories? replete with increasingly
accessible and progressively finer-grained data
(complementing Kahn?s 2000 recognition of
the sports industry as a ?labor market laboratory?)
. For example, taking advantage of
salary information that tends to be publicly available for high-profile sports (and for
which performance data is also available), numerous researchers have examined the
degree to which conflicts exist over how teams compensate members in relation to each
(e.g., Bloom 1999; Kniffin 2009; Trevor et al. 2012)
. At the individual level,
has found that people tend to be willing to trade relatively higher status in
exchange for relatively lower pay (and vice versa) when working as part of a close-knit
team. In light of this finding, it is sensible that current research is examining the
conditions under which (and the degree to which) teams can benefit as a function of
how individual members are compensated
(in money or other important currencies;
in relation to each other.
Fewell et al. (2012)
, for example, report that
NBA teams with more phenotypic uniformity in the distribution of ball-touches (an
important currency among players) tended to outperform teams whose plays tended to
rely disproportionately on a smaller number of higher-profile players. Given the wide
variety of rules and incentive structures across sports
, the lack of consensus
with respect to whether and how team-level allocation of resources might affect
teamlevel performance is not surprising. However, the fact remains that?as long as one
recognizes sport-specific rules and incentive structures?team sports offer public ?test
sites? for examining the relative importance of individual- and team-level interests.
The public nature of contemporary team sports also provides an arena for considering
the influence of ?nature? and ?nurture? in successful competitive behavior. Studies
regarding the social dynamics of sports typically treat biological variation as nonexistent.
For example, in a study comparing first-ballot Hall of Fame baseball players with other
Hall of Fame players,
Cotton et al. (2011)
find that players elected on the first ballot (i.e.,
elite among elite) tend to have richer developmental mentorship networks than the
comparison group. Although this finding is sensible and insightful, no consideration is
given to the possibility that biological differences exist between the two samples. Of
course, the application of biological perspectives to the study and management of team
sports has been muddled by now-discredited perspectives on race
contemporary work on the subject of gene-environment interactions is markedly more
sophisticated for questions focused on sports
(e.g., Epstein 2014)
as well as broader scopes
(e.g., Freese 2008; Freese and Shostak 2009)
. In this special issue, three of the
(Alvarado et al. 2018; Longman et al. 2018; McHale et al. 2018)
relationships between hormones and team sports participation and spectatorship,
generating insights that would obviously have been impossible if one were to assume that
biological variation is either nonexistent or irrelevant.
Team sports are attractive subjects of study because of their relative accessibility to
researchers and their naturalistic settings, but it is also true that the examination of sensitive
or carefully controlled questions benefits from the employment of field-based simulations
or laboratory experiments. Here,
Pollack et al. (2018)
Kruger et al. (2018)
findings from field-based simulations, and
Barbaro et al. (2018)
report findings from a lab
experiment. In all three cases, the research design entailed realistic scenarios where slight
but controlled variations allowed for between-subjects comparisons to conditions where
participants were randomly assigned. Pollack et al.?s test has relevance for any sports fan
who has watched elite players credit the supernatural for their success. Similarly, Kruger
et al. offer new perspectives on the dynamics that result when sports fans wear apparel
bearing the symbolically laden colors and logos of their favorite team.
The use of team sports as a model domain for studies of behavior and psychology
also provides an opportunity to demonstrate the value of evolutionary thinking for
contemporary commercial or applied purposes
(e.g., Roberts et al. 2012)
. Kruger et al.?s
study of the ways in which team-based apparel can influence the real-world interactions
of its wearers has both profit and safety implications. For example, although Kruger
et al. do not examine instances of rage or anger among fans, their findings offer
valuable baseline evidence for researchers and policymakers interested in better
understanding and preventing the kind of lethal violence that can occur when fans of a given
team are identified at a rival team?s home arena
(e.g., Swenson 2012)
Barbaro et al.?s findings, which examine the impact of video-game outcomes on
interpersonal decision-making, complement the massive and rapid growth of ?eSports.?
This development includes the growth of platforms, such as Twitch, that draw millions of
people to watch others play in various competitions. It also includes the emergence of
team-based virtual competitions: for example, the National Basketball Association has
commissioned its own ?mirror? league of teams that play a popular basketball video game
(Funk et al. 2018)
. As indicated by
Kasumovic et al.?s (2015
) application of evolutionary
perspectives to the perennial question of why people play violent video games, this type of
play is ripe for further investigation. The new frontier of virtual-team game play offers the
opportunity for substantial scaling and provides an arena for exploring issues of interest to
both academics and game developers
(e.g., increasing inclusivity across gender, class, and
ethnic barriers; see Mikulak 2015)
Two buzz-phrases commonly associated with the study of sports are ?sports
analytics? that utilize ?big data.? Typical topics for analytics include player evaluation
Kniffin et al. 2017; Lewis 2004)
, team-level strategy assessments
challenges to various concepts such as ?momentum?
(e.g., Kniffin and Mihalek 2014;
Tversky and Gilovich 1989)
. Both Kruger et al.?s and Barbaro et al.?s work can serve as
baselines for scaled-up research, and Kniffin and Palacio?s study of trash talk lends
itself to ?big data? collection, either through systematic collection and analysis of social
(e.g., Margolin and Liao 2018)
or through new technologies that would
allow unrestricted collection of audio communication among players.
study of tennis players is instructive: their use of ?machine learning?
methods, whereby players? emotions can be successfully classified on a play-by-play
basis through computer detection, highlights the unanticipated ways in which new
technology can benefit researchers as well as players and coaches. In sum, in alignment
with our overall goal to cultivate more consideration and analysis of sports from
multidisciplinary perspectives informed by evolutionary thinking, this special issue
showcases numerous windows for further explorations via the study of team sports that
employ a wide and growing array of methodological and analytical tools.
Acknowledgments The co-editors are grateful to each of the reviewers who kindly provided generous,
constructive feedback on the contributions to this issue. As co-authors of this Introduction, we also greatly
appreciate helpful communications with Louis Alvarado, Klaree Boose, Daniel Farrelly, Jane Lancaster,
Juneel Piper, and David Sloan Wilson.
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International
License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a
link to the Creative Commons license, and indicate if changes were made.
Kevin Kniffin has previously contributed to Human Nature, Evolution and Human Behavior, and American
Psychologist. Kniffin is a faculty member at Cornell University?s Dyson School of Applied Economics and
Management in the S. C. Johnson College of Business. His current streams of research focus on leadership and
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