ArticlePDF Available

Abstract and Figures

Play is an important aspect of dolphin life, perhaps even an essential one. Play provides opportunities for dolphin calves to practice and perfect locomotor skills, including those involved in foraging and mating strategies and behaviors. Play also allows dolphin calves to learn important social skills and acquire information about the characteristics and predispositions of members of their social group, particularly their peers. In addition to helping dolphin calves learn how to behave, play also provides valuable opportunities for them to learn how to think. The ability to create and control play contexts enables dolphins to create novel experiences for themselves and their playmates under relatively safe conditions. The behavioral variability and individual creativity that characterize dolphin play yield ample opportunities for individual cognitive development as well as social learning, and sometimes result in innovations that are reproduced by other members of the group. Although adults sometimes produce innovative play, calves are the primary source of such innovations. Calves are also more likely to imitate novel play behaviors than are adults, and so calves contribute significantly to both the creation and transmission of novel play behaviors within a group. Not unexpectedly, then, the complexity of dolphin play increases with the involvement of peers. As a result, the opportunity to observe and/or interact with other dolphin calves enhances the effects of play on the acquisition and maintenance of flexible problem solving skills, the emergence and strengthening of social and communicative competencies, and the establishment of social relationships. It seems that play may have evolved to help young dolphins learn to adapt to novel situations in both their physical and social worlds, the beneficial result being a set of abilities that increases the likelihood that an individual survives and reproduces.
Content may be subject to copyright.
Sciknow Publications Ltd. ABC 2014, 1(2):113-127
Animal Behavior and Cognition DOI: 10.12966/abc.05.03.2014
©Attribution 3.0 Unported (CC BY 3.0)
Why do Dolphins Play?
Stan A. Kuczaj1* and Holli C. Eskelinen2
1University of Southern Mississippi
2Dolphins Plus
*Corresponding author (Email: s.kuczaj@usm.edu)
Citation Kuczaj, S. A., & Eskelinen, H. C. (2014). Why do dolphins play? Animal Behavior and Cognition, 1(2),
113-127. doi: 10.12966/abc.05.03.2014
Abstract - Play is an important aspect of dolphin life, perhaps even an essential one. Play provides opportunities for
dolphin calves to practice and perfect locomotor skills, including those involved in foraging and mating strategies
and behaviors. Play also allows dolphin calves to learn important social skills and acquire information about the
characteristics and predispositions of members of their social group, particularly their peers. In addition to helping
dolphin calves learn how to behave, play also provides valuable opportunities for them to learn how to think. The
ability to create and control play contexts enables dolphins to create novel experiences for themselves and their
playmates under relatively safe conditions. The behavioral variability and individual creativity that characterize
dolphin play yield ample opportunities for individual cognitive development as well as social learning, and
sometimes result in innovations that are reproduced by other members of the group. Although adults sometimes
produce innovative play, calves are the primary source of such innovations. Calves are also more likely to imitate
novel play behaviors than are adults, and so calves contribute significantly to both the creation and transmission of
novel play behaviors within a group. Not unexpectedly, then, the complexity of dolphin play increases with the
involvement of peers. As a result, the opportunity to observe and/or interact with other dolphin calves enhances the
effects of play on the acquisition and maintenance of flexible problem solving skills, the emergence and
strengthening of social and communicative competencies, and the establishment of social relationships. It seems that
play may have evolved to help young dolphins learn to adapt to novel situations in both their physical and social
worlds, the beneficial result being a set of abilities that increases the likelihood that an individual survives and
reproduces.
Keywords - Dolphin play, Cognitive development, Social development, Moderately discrepant events, Flexible
problem solving
Play is notoriously difficult to define, regardless of the species that is playing (Burghardt, 2005;
Kuczaj & Horback, 2013). A determination of the precise reasons why animals play has also proven
evasive, perhaps because play serves a myriad of functions (see Bekoff & Allen, 1998; Burghardt, 2005;
Fagen, 1981; Groos & Baldwin, 1898; Kuczaj & Makecha, 2008; Pelligrini, 2011; Paulos, Trone, &
Kuczaj, 2010; Špinka, Newberry, & Bekoff, 2001). Despite the difficulty of defining and explaining play
to everyone’s satisfaction, it is usually easy to discriminate play and non-play behavior, and observations
and anecdotes concerning animal play abound in the literature.
Although play has been observed in many cetacean species (see Paulos et al., 2010, for a review
and summary), our focus in this paper will be on delphinid species, especially bottlenose dolphins
(Tursiops truncatus). The reason for this focus is simple. We know much more about play in dolphins
Kuczaj & Eskelinen 114
than we do about play in other cetaceans. Dolphins of all ages play, although play is more common in
young dolphins than in adult dolphins (Paulos et al., 2010). Does the fact that young dolphins play more
than older dolphins reflect developmental differences in the functions of play? Or do young dolphins
simply have more time and/or energy to play? In this paper, we examine possible reasons for
developmental differences in play among dolphins and for the prevalence of play in dolphins in general.
We conclude that play is an essential characteristic of dolphin life and that it serves a variety of functions
for dolphins. Some of these functions change with maturation while others remain constant throughout
the lifespan. But age is not the only factor that influences play in dolphins. Individual differences also
affect the amount and the types of play in which a dolphin engages. Consequently, it is necessary to
consider both ontogeny and personality in explanations of dolphin play.
What is dolphin play?
Dolphin play is multifaceted, and need not involve objects. Locomotor play occurs when dolphins
repeat or vary their own behavior (Paulos et al., 2010). Although aerial behaviors such as leaps, spins, and
breaches serve foraging and communicative functions (Lusseau, 2006; Würsig & Würsig, 1980), they
also occur in playful contexts in the wild (Bel’kovich, Ivanova, Kozarovitsky, Novikova, & Kharitonov,
1991; Würsig & Würsig, 1979, 1980) and in captivity (Trone, Kuczaj, & Solangi, 2005).
Dolphins do play with objects. In fact, as shown in Table 1, dolphins will play with virtually
anything. Dolphins maintained in captivity play with objects they are given (e.g., balls, buoys, and ropes),
objects they find (e.g., feathers, hats, and wallets), objects they create (bubbles and bubble rings), animals
they capture to use as toys (e.g., birds, fish, eels), prey items that are played with prior to being consumed
(fish and eels), and animals that are unwittingly and unwillingly treated as play objects (e.g., sea stars, sea
turtles, sharks). Humans rarely provide wild dolphins with toys, but wild dolphins will play with objects
that they happen upon (e.g., plastic, sea weed), objects they produce (bubbles), animals that will not be
consumed (birds, jelly fish, sperm whales), and prey animals that may or may not be eaten after the play
bout is completed (fish).
Table 1
Examples of Objects used in Play by Various Species in Captivity and in the Wild
Species
Wild
Captive
Amazon River dolphin
(Ina geoffrensis)
fish, seaweed, wood
bubbles, pool cleaning equipment
Atlantic spotted dolphin (Stenella frontalis)
bottlenose dolphin, bubbles, sea
turtle, seaweed
Bottlenose dolphin
(Tursiops truncatus)
bird, cape fur seal, fish, harbor
porpoise, humpback whale,
jellyfish, seaweed, sperm whale
balls, bird, bubbles, buckets, buoys,
coins, eel, feather, fish, gauze, hoops,
net, pool cleaning equipment, plastic
bag, ropes, rubber objects, sea lion,
seaweed, scarves, shark, skate/ray,
sunglasses, tape, wallet, water hose,
water spraying/spitting, wood
Kuczaj & Eskelinen 115
Common dolphin
(Delphinus delphis)
sea turtle
fish
Estuarine dolphin
(Sotalia fluviatilis)
seaweed, plastic bags, wood
Dusky dolphin
(Lagenorhynchus obscrus)
bird, seaweed, South American sea
lion, Southern right whale
False killer whale
(Pseudorca crassidens)
ball
Hawaiian spinner dolphin (Stenella longirostris)
Seaweed
towel
Harbor porpoise
(Phocoena phocoena)
sea star
Hector’s dolphin (Cephalorhynchus hectori)
Seaweed
Indo-Pacific dolphin
(Sousa chinensis)
sea turtle
Killer whale
(Orcinus orca)
birds, sea turtle
ball, birds
Long-beaked common dolphin
(Delphinus capensis)
sea turtle
Pacific white-sided dolphin
(Lagenorhynchus obliquidens)
sea turtle
feather
Pantropical spotted dolphin
(Stenella attenuata)
sea turtle
Pilot whale
(Globicephala)
bird, sea turtle
rubber tire
Rough-toothed dolphin
(Steno bredanensis)
artificial swim leg, fish, jellyfish,
plastic bag, puffer fish, sea turtle,
seaweed, sperm whale
buoy, hoop
Spinner dolphin
(Stenella longirostris)
sea turtle
Striped dolphin
(Stenella coeruleoalba)
sea turtle
Table 1 (cont.)
Kuczaj & Eskelinen 116
Figure 1. A five-month-old dolphin calf plays with a piece of sargassum (Sargassum muticum).
Dolphins also play with one another. In a longitudinal study of three dolphin calves, the relative
frequency and the complexity of social play were found to increase throughout the first year of life
(Mackey, Makecha, & Kuczaj, 2014). This pattern has also been observed in other species. For example,
kittens (Felis catus: West, 1974), Cuvier’s gazelles (Gazella cuvieri: Gomendio, 1988), and hyenas
(Hyaenidae: Drea, Hawk, & Glickman, 1996) all tend to engage in more interactive social play as they
mature. Mackey et al. (2014) found that the mother was typically a dolphin calf’s first social play partner.
However, calf social play became increasingly likely to involve another calf rather than the mother
shortly as calves matured. Calves also became more likely to seek out others for social play bouts with
increasing age and so were more likely to initiate social play interactions as they matured and less likely
to be solicited by other dolphins for a play bout. Young calves preferred to play with calves of similar
ages, but became more likely to play with older calves as they themselves grew older. Thus, a four-
month-old calf might prefer to interact with other calves close to its age, but the same calf at 10 months of
age might be equally likely to play with a 24 month old as with other 10 month olds. Playing with older
animals and attempting to mimic the older calves’ more advanced play behaviors are aspects of a more
general tendency for dolphin calves to increase the challenging aspects of their play as they mature
(Kuczaj, Makecha, Trone, Paulos, & Ramos, 2006).
So far, we have provided a brief overview of dolphin play in order to provide a general sense of
the characteristics of such play. More in depth considerations of dolphin play can be found in Kuczaj et
al. (2006), Kuczaj & Horback, 2013, Mackey et al. (2014), and Paulos et al. (2010), but our quick dip into
the pool of dolphin play is sufficient for us to turn to the main purpose of this paper attempting to
explain why dolphins play.
Kuczaj & Eskelinen 117
Why do dolphins play?
“Why do dolphins play?” seems like a simple question, but there is no simple answer. Dolphins
play for a number of reasons, and an explanation of dolphin play must take into account all of these
purposes.
Dolphins play because they are young. Adult dolphins play, so it is erroneous to conclude that
only young dolphins play. However, it is true that dolphin calves and juveniles play more than adult
dolphins (Paulos et al., 2010; Würsig & Würsig, 1979). Dolphins are similar to other species in this
regard (Burghardt, 2005; Pellegrini, 2011; Fagen, 1981). Although the negative correlation between age
and play does not explain why dolphins (young or old) play, it is nonetheless an important aspect of
dolphin play.
Given that young animals are more likely to play than are older animals, many theorists have
suggested that play is developmentally significant (Bjorklund & Pelligrini, 2010; Erikson, 1977; Kuczaj
et al., 2006; Kuczaj & Walker, 2012; Martin & Caro, 1985; Pellegrini, 2011; Piaget, 1962; Vygotsky,
1978). For example, play may help the young of a species to develop important social skills and
knowledge (Bekoff & Byers, 1981; Connoly & Doyle, 1984; Pellis & Pellis, 2007; Piaget, 1962;
Vygotsky, 1978). Determining one’s place in a social network, learning to identify and interact with
members of one’s group, and discovering how to regulate one’s own emotions and interpret the emotional
states of others are all important developmental accomplishments for social species, and play may benefit
the acquisition of these social skills (Bekoff & Byers, 1981; Fagen, 1981; Gottman, 1986; Kuczaj &
Horback, 2013; Martin & Caro, 1985; Pellis & Pellis, 2009).
Dolphins play because playing is fun and/or pleasurable. Early explanations of play
emphasized the pleasurable nature of play (Buhler, 1935; Buytendijk, 1933; Gilmore, 1966), the general
idea being that playing is fun. More recently, one of the leading scholars of animal play included the
“pursuit of pleasure” in his list of play functions (Burghardt, 2005). Animals, including dolphins, play
because doing so is fun. But even if dolphins are motivated to play because such activities are
pleasurable, the functions that play serves go beyond the simple pursuit of fun. Play may have evolved to
serve a wide range of functions, the pleasure that is associated with play insuring that animals (especially
young animals) do the homework that nature has assigned them by playing.
Although pleasure and play are intimately linked, it is not the case that play is always fun
(Burghardt, 2005). The veneer of pleasure that accompanies play is sometimes thin, and may vanish
altogether. A pleasurable play experience can quickly change into an experience that produces more
negative emotions (Burghardt, 2005). The following example was provided by Kuczaj and Horback
(2013):
We witnessed an example of solitary play changing from fun to surprise
when a young dolphin playing with a large crab had the tables turned on
him by the crab. The dolphin was grabbing the crab with its mouth,
carrying the crab for a distance, releasing the crab, and then catching the
crab before the crab settled to the bottom. This behavior continued until
the overly confident dolphin nonchalantly mouthed the crab and received
a pinch on its tongue for its efforts. This was immediately followed by a
dolphin yelp and the dolphin hurrying back to its mother. What had
started out as a pleasurable experience for the dolphin (but perhaps not
for the crab) became a painful one, at which time the play bout ended (p.
96).
Although the young dolphin in the above example may not have realized it was taking a risk with
the crab, dolphins do sometimes play in ways that suggest they are testing the boundaries of safety.
Kuczaj & Eskelinen 118
Deakos, Branstetter, Mazzuca, Fertl, and Mobley (2010) observed dolphins playing with humpback
whales (Megaptera novaeangliae) by swimming above a whale’s head until the whale lifted its head and a
dolphin out of the water, resulting in the dolphin sliding down the whale’s head into the water. This
behavior was repeated, suggesting that it was a form of play for the dolphins and perhaps even the whales.
This is certainly a risky play activity for the dolphins, and it may be this unusual risk that motivated the
behavior.
Similarly, we have observed dolphins housed in pools with ledges balancing on ledges that
separate pools or are the top of an exterior wall. This behavior is not encouraged by oceanarium staff
since dolphins that balance themselves on a thin ledge on an exterior wall are at risk of falling to the floor
of the outside area surrounding the pool, a fall that could injure the dolphin. We suspect that the challenge
of balancing oneself on a ledge is stimulating for the dolphins that engage in the balancing game, a
behavior that is certainly not part of their natural repertoire. However, just as playing with a humpback
whale places a dolphin at risk, dolphins that choose to balance on ledges risk injury if they lose their
balance and fall outside of their enclosure.
Social play also has the potential to become dangerous. Social play fights are common among
young animals, but play fights become more likely to escalate into actual fights with increasing age
(Burghardt, 2005; Kuczaj & Horback, 2013; Pellis & Pellis, 1996; Power, 2000; Sommer & Mendoza-
Granados, 1995). The sometimes sudden transition from play to aggression may reflect the multitude of
emotions that accompany play (Burghardt, 2005). Play provides a safe means for young animals to
experience a variety of emotions (Burghardt, 2005; Kuczaj & Horback, 2013; Singer & Singer, 1990;
Sutton-Smith, 2003, 2011), but emotional changes during a play bout can sometimes result in a playful
context being transformed into a more serious and sometimes dangerous one. Although we do not know
exactly how dolphins interpret the emotions of other dolphins, the nature of their social interactions
suggest that they are able to do so (Kuczaj, Highfill, Makecha, & Byerly, 2013). Learning more about the
manner in which young dolphins develop the skills necessary to interpret the emotions of others will
increase our understanding of both dolphin play and dolphin life in general.
Dolphins play to practice important behaviors. The notion that play provides opportunities for
animals to practice important skills is prevalent in the play literature (see Burghardt, 2005; Byers &
Walker, 1995; Fagen, 1981; Kuczaj & Horback, 2013; Kuczaj & Makecha, 2008) for more detailed
considerations of this hypothesis). For example, the exercise involved in locomotor play helps to
strengthen and condition a young animal’s developing body and so improves its overall physical
condition. Locomotor play also provides opportunities for animals to practice behaviors such as creeping,
sprinting and leaping, such play helping young prey animals develop essential anti-predator escape
behaviors and young predator animals to perfect their hunting skills (Byers & Walker, 1995; Caro, 1995;
Power, 2000; Špinka et al., 2001).
One form of solitary play that has rarely been studied in non-human animals concerns
communication systems. Young human children play with sounds, words, and word combinations as they
acquire their first language (Kuczaj, 1982, 1983; Weir, 1962), and it is possible that young dolphins might
play with sounds as they develop their acoustic repertoire (Kuczaj, in press; Kuczaj & Makecha, 2008).
Dolphin calves must learn to produce the sounds that will comprise the acoustic part of their
communicative system, and experience is an important component of this process (Fripp et al., 2005). We
strongly suspect that calves play with sounds and sound combinations as they consolidate the whistles,
barks, squawks, burst pulses and other sounds that they will use to communicate. They may even play
with echolocation clicks as they master this essential sensory system.
Social play also provides opportunities for young animals to practice behaviors that could prove
useful in later life. Physical play with conspecifics can facilitate the acquisition of behaviors used in
foraging, hunting, fleeing, courtship and mating, and fighting (Vieira & Sartorio, 2002). So even though
physical social play typically involves members of the same species, the behaviors that are practiced in
such play can influence interactions with members of other species as well as members of their own
social group.
Kuczaj & Eskelinen 119
It is important to remember that the practice that occurs during play is not forced repetition, but
instead spontaneous behavior that is typically quite exuberant. As Kuczaj and Horback (2013) noted,
The practice that occurs during play is neither mundane nor boring.
Instead, the play context provides an intrinsically reinforcing scenario in
which children and young animals enjoy the activities in which they are
engaging, the result being a much more efficient learning session than
one in which youngsters’ attention is being directed by others (p. 105).
As noted earlier, play can be dangerous. Animals must be aware of potential dangers in order to
avoid being injured or killed while practicing physical skills or play jousting with another. They must also
be sensitive to the emotional state of their play partner. Otherwise, a play fight could quickly transform
itself into something more serious. But the risk itself may be motivating in some cases, such as dolphins
balancing on a ledge or a young animal seeing just how far it can go in a play fight with an older animal
before the consequences become dangerous. We suspect that personality plays a role in this, with some
animals more likely to be reinforced by risk-taking than others.
Dolphins play because other dolphins are playing. Dolphin play is contagious. An object
becomes more interesting to dolphins if another dolphin plays with it. Dolphins of all ages become
interested in the objects with which other dolphins are interacting, even if the objects had been ignored by
these same dolphins prior to the play activity or are commonplace in their environment. Stimulus
enhancement of this sort is a form of observational learning and explanations of why dolphins’ interest in
objects is piqued by other dolphin’s play will likely involve considerations of social status, personality,
and social learning.
Figure 2. A young dolphin plays with an object it found on the seabed while another dolphin watches.
Kuczaj & Eskelinen 120
We do know that the play of dolphin calves is strongly influenced by other calves. Calves
produce play behaviors earlier in life if they have the opportunity to observe other (typically older) calves
engaging in the same behaviors (Kuczaj et al., 2006). Calves are also more likely to imitate novel play
behaviors produced by other calves than by those produced by adults, including their mothers (Kuczaj et
al., 2006). This preference for some models over others demonstrates that not all models are equally
interesting. Instead, some models are more salient than others, the saliency of a model reflecting the
characteristics of the model, the characteristics of the observer, and the context in which the modeled
behavior occurs.
The important point is that dolphin calves are neither indiscriminate observers of other dolphins’
behaviors nor mindless mimics of behaviors they witness. Their social learning is selective, and they
choose who to observe and who to imitate depending on the behavioral context (Kuczaj, Yeater, &
Higfill, 2012). Learning to forage is a critical survival skill for wild dolphins, and observing and
mimicking the foraging strategies of its mother increases a calf’s chances of surviving (Addink &
Smeenk, 2001; Bender, Herzing, & Bjorklund, 2009; Holmes & Neil, 2012; Krützen, Mann, Heithaus,
Connor, Bejder, & Sherwin, 2005; Lodi & Hetzel, 1999; Smeenk, Addink, & Richards, 1995). However,
the play context is different. Other calves that are playing are much more interesting than the calf’s
mother, and so calves are more likely to watch and imitate the play behaviors of other calves. Of course,
this depends on both a calf’s personality and the mother’s style (if the mother will let them play with
others; see Hill, Kuczaj, Greer, & Solangi, 2007, for a discussion of maternal styles in dolphins). Berger
(1980) found that bighorn sheep (Ovis canadensis) lambs that rarely left their mothers engaged in contact
play with other lambs at later ages than did lambs that were allowed to frolic with other youngsters at an
earlier age, and we suspect that the same patterns occur for dolphin calves. The extent to which a calf’s
independent behavior (or its lack) reflects its personality or its mother’s maternal style likely varies from
mother-calf pair to mother-calf pair.
Exploratory play appears to facilitate the imitation of novel behavior (Miklósi, 1999), and so
observing other dolphins playing may encourage calves to attempt to reproduce the play behaviors they
witness. Perhaps they are more likely to mimic other calves because calves are more similar to one
another in body size than are any calf and adult, this similarity making it easier to interpret, remember,
and reproduce the observed behavior (Kuczaj et al., 2006; Yando, Seitz, & Zigler, 1978). The tendency to
observe and mimic other calves’ play behaviors may have also evolved as a means to the increase the
social cohesiveness of a calf group (Kuczaj et al., 2006). Adult humans that are imitated are more likely
to be helpful and generous to others (not just the mimicker), suggesting that imitation may increase
prosocial behavior in a group (van Baaren, Holland, Kawakami, & Knippenberg, 2004). This led Kuczaj
and colleagues (Kuczaj et al., 2006) to speculate that dolphin calves may be predisposed to observe and
mimic other calves as a means to facilitate and maintain positive social interactions within the peer group.
Why are some calves more preferred models than others? Older calves are frequently imitated by
younger calves because the older calves produce behaviors that the young animals do not know, the
novelty of witnessing another dolphin almost its own size producing novel (to the young dolphin)
behaviors apparently increasing the saliency of the behaviors (Chirigin, 1987; Kuczaj et al., 2006;
Mackey et al., 2014). This supposition is supported by the finding that dolphin calves produce more
complex play behaviors at an earlier age if there are older calves in their social groups (Kuczaj et al.,
2006). Being able to observe older calves appears to motivate younger calves to attempt play behaviors at
an earlier age than they would otherwise, and also seems to increase the overall complexity of the young
calves’ play behavior repertoire. This pattern is not found in all species. For example, infant sable
antelopes (Hippotragus niger) prefer same age play partners (Thompson, 1996).
Although older calves are more likely to be mimicked than are same-age or younger peers, age is
not the sole factor that determines the saliency of a model. Dolphins have distinct individual personalities
(Highfill & Kuczaj, 2007, 2010; Kuczaj, Highfill & Byerly, 2012), and a dolphin’s personality influences
the extent to which other dolphins attend to and attempt to reproduce its behavior (Kuczaj, Yeater &
Highfill, 2012). The bolder and more curious dolphins are more likely to be observed and mimicked than
are the timid and cautious dolphins. For example, when dolphins first encountered a swimmer with an
Kuczaj & Eskelinen 121
artificial swim leg, the bolder calves and juveniles were the first to examine the leg, swimming close to it,
orienting and echolocating on it (Kuczaj et al., 2012). In contrast, the more cautious calves remained a
short distance behind the bolder animals, always kept the bold animal between themselves and the novel
object, and watched the bold calf’s behavior intently. The bold animals quickly became more
adventurous, gently mouthing and sometimes even lightly pulling on the leg. The cautious dolphins did
not interact with the leg until they had witnessed the bolder animals’ interactions with it, and the cautious
animals’ interactions were invariably attempts to replicate what they had observed the bolder animals
doing. These and similar results demonstrate that dolphin social learning is selective, and is influenced by
a number of factors: behavioral context, novelty of behavior and/or model, the social significance of the
model, and personality (Kuczaj et al., 2012).
As noted above, young dolphins may acquire important social skills during play and may
challenge themselves by playing with more competent peers or even adults. During social play, an older
and/or more adept animal may opt to handicap itself to both encourage playful interactions with a younger
animal and to avoid injuring the youngster. If the dolphins are playing a social game, such as play-
fighting or play-mating, the more dominant animal may play a subordinate role, such role reversals being
rarely observed outside of the play context.
A young or subordinate animal that wishes to play with a stronger or more dominate conspecific
must be certain that the other wants to play. Part of this assessment rests on an ability to correctly
ascertain the emotional state of the other dolphin (Kuczaj & Horback, 2013). This assessment is
simplified if there is a play signal that is used to signal willingness to play.
Social play is only possible if the players communicate with one another in order to establish
common “play frames” (Bateson, 1955, 1972; Sutton-Smith, 1980). Play signals are used to communicate
playful intent, helping to insure that behaviors that occur in a playful context are not interpreted as
seriously as they would be in a non-play context (Bateson, 1955, 1972). Such signals have been
discovered in numerous species (Burghardt, 2005; Kuczaj & Horback, 2013; Palagi, 2009; Pellis & Pellis,
2011), and it is possible that dolphins also use play signals.
One acoustic play signal has been observed in captive dolphins, and occurs during play-fight
contexts (Blomqvist, Mello, & Amundin, 2005). Play-fighting is a common context in which play signals
are observed, most likely because such play fights can escalate into real fights and it is important to
monitor the emotional state of one’s opponents in order to maintain and even repair the playful context
(Kuczaj & Horback, 2013). Another possible dolphin play signal was reported by Kuczaj and Makecha
(2008). They observed dolphin calves remaining stationary on the surface of the water, a behavior that
usually resulted in another young dolphin approaching the stationary animal and pushing it sideways
through the water. Kuczaj and Makecha proposed that the stationary floating behavior signaled
“willingness to be pushed” to other calves. This behavior was only produced during play contexts and
always resulted in the floating dolphin either being ignored by other dolphins or being pushed sideways
along the surface of the water. If the floating dolphin was pushed, it sometimes solicited another push by
assuming the surface floating position again. But in some cases, two dolphins took turns, alternating the
roles of “pusher” and “pushee. Cooperative play requires communication, and Kuczaj and Makecha
suggested that the surface floating behavior was an essential play signal for this dolphin game.
Play signals have not been observed in wild dolphins, but it seems likely that similar signals exist
in wild populations. Young dolphins engage in play fights in the wild as well as in captivity, and the need
to communicate playful intent is important in both contexts. Adult rough-toothed (Steno bredanensis)
dolphins play with younger animals (Kuczaj & Highfill, 2005), and it is possible that adults use a play
signal to encourage the younger animals’ participation.
Specific play signals are not used in all forms of social play, and so playful intent must be
communicated in other ways. If a species has evolved the ability to reliably interpret the emotional states
of others, the positive emotions associated with play may be the only information that is needed to
communicate a play context (Kuczaj & Horback, 2013). But dolphins may also use other cues such as the
overall social context to hazard guesses about other’s behavioral intentions. Chimpanzees (Pan
troglodytes) interpret the overall context as well as facial expressions in emotional scenarios (Kano &
Kuczaj & Eskelinen 122
Tomonaga, 2010), and Kuczaj and Horback (2013) suggested that animals might also use a variety of
cues to assess playfulness in others.
Dolphins play to challenge themselves. Dolphin play is dynamic and becomes more complex
with increasing age (Kuczaj et al., 2006; Kuczaj & Horback, 2013; Kuczaj & Makecha, 2008; Kuczaj &
Walker, 2012; McBride & Hebb, 1948; Tavolga, 1966). Kuczaj et al. (2006) suggested that dolphins
modify their play to keep it interesting and reinforcing. In one example they provided, a calf became
proficient at blowing bubbles while swimming upside-down near the bottom of the pool and then chasing
and biting each bubble before it reached the surface of the water. Once she was proficient at this, she
modified her behavior by varying the number of bubbles released and the depth at which she released
bubbles, her apparent goal being to catch the last bubble right before it reached the surface of the water.
At one point, she began to release bubbles while swimming closer and closer to the surface, eventually
being so close when she emitted bubbles that she could not catch a single bubble. Despite this failure, she
persisted releasing bubbles near the surface until she had determined the absolute closest she could be to
the surface and still catch and bite a bubble she produced. She also altered her swimming style while
releasing bubbles, one variation involving a fast spin-swim. Producing bubbles during a swim-spin
decreased her chances of biting all of the bubbles she released, but she practiced this behavior until she
could catch most of the released bubbles. Thus, the dolphin controlled the difficulty of the game, striving
to make it as difficult as possible yet still succeeding in biting all the bubbles she produced.
Observations of a dolphin calf at Dolphins Plus in Key Largo, Florida, yielded another example
of play becoming more complex over time for an individual animal. Animals at this facility are housed in
semi open ocean pens, which provide the dolphins with a variety of objects with which to play. Dolphin
calves begin playing with grass, seaweed, algae and mangrove seedpods during the first month of life,
typically by carrying the objects in their mouth. Detailed observations of one calf revealed that the young
male began playing with mangrove seedpods, leaves and other fauna by placing them in his mouth or on
the front of his rostrum. Around three months of age, he began to carry and balance the target objects on
the front of his pectoral fins or dorsal fin. Approximately two months later, the calf began transferring the
play object from one part of his body to another (e.g., from one pectoral fin to the other), as well as letting
it slide down the ventral side of his body and then hitting it with his fluke. What began as simple
exploratory play (mouthing objects) evolved into more complex forms of play is relatively short order.
Observations such as this led Kuczaj et al. (2006) to conclude that dolphins used play to create
moderately discrepant events. Piaget (1952) proposed that the moderately discrepant events created by
human children were essential aspects of their cognitive development because such events are both
familiar and novel. The familiar aspect is important because it provides the child (or dolphin) a basis for
interpreting the novel component of the situation, the successful interpretation of the novel aspect
resulting in cognitive growth. This in turn provides a slightly more complex familiar basis to help
interpret for a more complex event, a cycle that repeats itself throughout development to eventually yield
a mature cognitive system.
Play provides a context in which dolphins are free to create their own moderately discrepant
events, something they most likely do because challenging oneself is what keeps play interesting.
Repeating the same behavior over and over again becomes boring, as does playing any sort of game that
is too easy for one’s abilities. Boredom is aversive and occurs when an organism is unable to engage in a
satisfying activity (Eastwood, Frischen, Fenske, & Smilek, 2012; Kuczaj et al., 2002), and challenging
oneself during play enables that player to keep play satisfying. Kuczaj and Horback (2013) speculated
that evolution may have selected for individuals that sought the challenges afforded by increasing the
complexity of their play environments. As a result, even though dolphins do not intend this consequence,
the creation of moderately discrepant events during play enhances cognitive development, including the
ontogeny of flexible problem solving skills. Perhaps evolution has selected for individuals that seek the
challenges provided by increasing the complexity of their play environments, as suggested by Kuczaj and
Horback (2013).
Kuczaj & Eskelinen 123
The Significance of Play
Play serves a variety of important functions, ranging from the simple pursuit of pleasure to the
facilitation of cognitive skills (Burghardt, 2005). Play facilitates neuromuscular development, enhances
motor skills, increases adaptability and flexibility both behaviorally and cognitively, and provides
opportunities to practice and perfect social and communicative skills to be used in more serious affiliative
and agnostic contexts (Bekoff, 2001; Bekoff & Byers, 1981; Coelho & Bramblett, 1982; Kuczaj &
Horback, 2013; Kuczaj et al., 2006; Thompson, 1996; West, 1974). The social significance of play rests at
least in part on the experiences it provides for players to learn to produce appropriate emotional responses
in a variety of contexts (Bekoff, 2002; Colvin & Tissier, 1985; Fagen & Fagen, 2004; Kuczaj & Horback,
2013; Pellis & Pellis, 2009; Singer & Singer, 1990).
An important aspect of dolphin play concerns their predisposition to challenge themselves during
play. Why do dolphins make their play more difficult? One reason is that challenging themselves during
play keeps play interesting. Play provides a context in which dolphins can create their own moderately
discrepant events, and so insure that their play remains stimulating. In turn, this may facilitate the
ontogeny and maintenance of flexible problem solving skills. The presence of other playing animals is
another driving force for increasingly complex play. Although the presence of other calves is not
necessary for an individual calf’s play to become more complex, the opportunity to interact with and
observe other calves results in increasingly complex forms of play. This may occur because dolphin
calves attempt to reproduce complex behaviors that older calves model and/or because calves strive to
outdo one another (although there are undoubtedly individual differences in this regard), perhaps as they
try to establish their social rank within the group. However, it is not only dolphin calves that challenge
themselves during play. Adult dolphins also make their play more complex, and it is possible that dolphin
play helps to maintain cognitive functioning throughout the life span.
Dolphin interest in the play of others may help us to understand the processes involved in the
creation and maintenance of animal culture (Kuczaj et al., 2006). The transmission of cultural information
necessitates some form(s) of social learning (Boyd & Richerson, 1996; Rendell & Whitehead, 2001) and
so requires that an individual be able to learn via observation or teaching from another individual. Avital
and Jablonka (2000) suggested that much of the information that constitutes animal culture is acquired
during ontogeny. The existing data on dolphin play are consistent with this view, and highlight the role of
peers in cultural transmission and innovation (Kuczaj et al., 2006). Dolphin calves appear to be key
players in both the transmission and creation of the behaviors that comprise a group’s culture, and the
same may be true for the young of other social species. Additional research is needed to examine the
relative roles of peers and adults in the acquisition of various forms of behaviors in a variety of species
and contexts to determine the extent to which this hypothesis is true.
Conclusions
As we have seen, dolphins play for a variety of reasons. Dolphin calves play more than older
dolphins, but adult dolphins also play. The functions and types of play in which dolphins engage change
as dolphins mature. Locomotor play is more common in young dolphins than in adults. Such play
facilitates muscular growth and coordination, and so is more important for growing animals that are
learning about and testing the capacities of their bodies. Dolphin calves are also more likely to practice
behaviors during play than are adults, a difference that once again reflects the greater need for young
animals to perfect behaviors that will be used in foraging, mating, evading predators, and various forms of
social interactions. Adult dolphins have learned these skills, and so have little need to practice them
during play. Locomotor play by adult dolphins, although relatively rare compared to that of calves, may
help adults maintain their physical strength, stamina, and flexibility.
Another developmental difference in dolphin play concerns the behavioral contagion of play.
Young dolphins are very intrigued by the play of other dolphins, and are likely to either join in the play
activity or closely observe it. Although some adult dolphins join in the play activities of others, adults are
Kuczaj & Eskelinen 124
more likely to be unaffected by the play of others, the exception being when a novel object is involved.
This developmental difference may reflect the fact that young dolphins are in general more interested in
play than are adults. Or it might be due to adults having witnessed many types of play in their lives,
decreasing the chances that they will find the play of others noteworthy. This possibility is supported by
observations of adult dolphins attending to play that involves novel behaviors.
Dolphins of all ages challenge themselves during play, although this tendency appears to be more
prevalent in young dolphins. Creating moderately discrepant events facilitates the growth of flexible
problem solving skills, a crucial aspect of ontogeny for young dolphins. Adult dolphins that challenge
themselves during play may be helping themselves maintain the critical cognitive skills that were
acquired when they were young.
To sum up, play is an essential characteristic of dolphin life that serves a variety of functions.
Both age and personality influence amounts and types of dolphin play. Additional work is needed to
determine the manner in which individual differences affect the creativity of dolphin play, interest in the
play of other dolphins, and curiosity about novel objects throughout the lifespan.
References
Addink, M. J., & Smeenk, C. (2001). Opportunistic feeding behaviour of rough-toothed dolphins Steno bredanensis
off Mauritania. Zoologische Verhandelingen, 29, 37-48.
Avital, E., & Jablonka, E. (2000). Animal traditions: Behavioural inheritance in evolution. New York, NY:
Cambridge University Press.
Bateson, G. (1955). A theory of play and fantasy. Psychiatric Research Reports, 2, 3951.
Bateson, G. (1972). Steps to an ecology of mind. New York, NY: Ballantine Books.
Bekoff, M. (2001). Social play behaviour. Cooperation, fairness, trust, and the evolution of morality. Journal of
Consciousness Studies, 8, 81-90.
Bekoff, M. (2002). Minding animals: Awareness, emotions, and heart. New York, NY: Oxford University Press.
Bekoff, M., & Allen, C. (1998). Intentional communication and social play: How and why animals negotiate and
agree to play. In M. Bekoff & J. A. Byers (Eds.), Animal play: Evolutionary, comparative, and ecological
perspectives (pp. 97114). New York, NY: Cambridge University Press.
Bekoff, M., & Byers, J. (1981). A critical reanalysis of the ontogeny of mammalian social and locomotor play: An
ethological hornet’s nest. In W. Barlow, K. Immelman, & L. Petrinovich (Eds.), Behavioural
development: The Bielefield interdisciplinary project (pp. 296-337). New York, NY: Cambridge
University Press.
Bel’kovich, V. M., Ivanova, E. E., Kozarovitsky, L. B., Novikova, E. V., & Kharitonov, S. P. (1991). Dolphin play
behavior in the open sea. In K. Pryor & K. S. Norris (Eds.), Dolphin societies: Discoveries and puzzles
(pp. 67-77). Los Angeles, CA: University of California Press.
Bender, C. E., Herzing, D. L., & Bjorklund, D. F. (2009). Evidence of teaching in Atlantic spotted dolphins
(Stenella frontalis) by mother dolphins foraging in the presence of their calves. Animal Cognition, 12, 43-
53.
Berger, J. (1980). The ecology, structure and functions of social play in bighorn sheep (Ovis canadensis). Journal of
Zoology, 192, 531-542.
Bjorklund, D. F., & Pelligrini, A. D. (2010). Evolutionary perspectives on social development. In P. K. Smith & C.
H. Hart (Eds.), The Wiley-Blackwell handbook of childhood social development (pp. 64-81). Oxford, UK:
Wiley-Blackwell.
Blomqvist, C., Mello, I., & Amundin, M. (2005). An acoustic play-fight signal in bottlenose dolphins (Tursiops
truncatus) in human care. Aquatic Mammals, 31, 187.
Boyd, R., & Richerson, P. J. (1996). Why culture is common but cultural evolution is rare. Proceedings of the
British Academy, 14, 113-118.
Buhler, C. (1935). From birth to maturity: An outline of the psychological development of the child. London, UK:
Routledge & Kegan Paul.
Burghardt, G. M. (2005). The genesis of animal play: Testing the limits. Cambridge, MA: MIT Press.
Buytendijk, F. J. J. (1933). Das Verhalten von Octopus Nach teilweiser Zerstorung des “Gehirns” [The behavior of
Octopus after partial destruction (or removal) of its brain]. Archives Neerlandaises de Physiologie de
l'Homme et des Animaux, 18, 2470.
Kuczaj & Eskelinen 125
Byers, J. A., & Walker, C. (1995). Refining the motor training hypothesis for the evolution of play. American
Naturalist, 146, 25-40.
Caro, T. M. (1995). Short-term costs and correlates of play in cheetahs. Animal Behaviour, 49, 333-345.
Chirigin, L. (1987). Mother-calf spatial relationships and calf development in the captive bottlenose dolphin
(Tursiops truncatus). Aquatic Mammals, 13, 5-15.
Coelho, A. M., & Bramblett, C. A. (1982). Social play in differentially reared infant and juvenile baboons (Papio
sp). American Journal of Primatology, 3, 153-160.
Colvin, J. D., & Tissler, G. (1985). Affiliation and reciprocity in sibling and peer relationships among free-ranging
immature male rhesus monkeys. Animal Behaviour, 33, 959-977.
Connoly, J. A., & Doyle, A. B. (1984). Relation of social fantasy play to social competence in preschoolers.
Developmental Psychology, 20, 797-806.
Deakos, M. H., Branstetter, B. K., Mazzuca, L., Fertl, D., & Mobley, J. R., Jr. (2010). Two unusual interactions
between a bottlenose dolphin (Tursiops truncatus) and a humpback whale (Megaptera novaeangliae) in
Hawaiian Waters. Aquatic Mammals, 36, 121-128.
Drea, C. M., Hawk, J. E., & Glickman, S. E. (1996). Aggression decreases as play emerges in infant spotted hyenas:
Preparation for joining the clan. Animal Behaviour, 51, 1323-1336.
Eastwood, J. D., Frischen, A., Fenske, M. J., & Smilek, D. (2012). The unengaged mind defining boredom in terms
of attention. Perspectives on Psychological Science, 7, 482-495.
Erikson, E. H. (1977). Toys and reasons: Stages in the ritualization of experience. New York, NY: Norton &
Company.
Fagen, R. (1981). Animal play behavior (pp. 102-112). New York, NY: Oxford University Press.
Fagen, R., & Fagen, J. (2004). Juvenile survival and benefits of play behaviour in brown bears, Ursus arctos.
Evolutionary Ecology Research, 6, 89-102.
Fripp, D., Owen, C., Quintana-Rizzo, E., Shapiro, A., Buckstaff, K., Jankowski, K., & Tyack, P. (2005). Bottlenose
dolphin (Tursiops truncatus) calves appear to model their signature whistles on the signature whistles of
community members. Animal Cognition, 8, 17-26.
Gilmore, J. B. (1966). The role of anxiety and cognitive factors in children's play behavior. Child Development, 37,
397-416.
Gomendio, M. (1988). The development of different types of play in gazelles: Implications for the nature and
functions of play. Animal Behaviour, 36, 825-836.
Gottman, J. M. (1986). The world of coordinated play: Same- and cross-sex friendship in children. New York, NY:
Cambridge University Press.
Groos, K., & Baldwin, E. L. (1898). The play of animals. New York, NY: D. Appleton and Company.
Highfill, L. E., & Kuczaj, S. A., II (2007). Do bottlenose dolphins (Tursiops truncatus) have distinct and stable
personalities? Aquatic Mammals, 33, 380-389.
Highfill, L. E., Kuczaj, S. A., II (2010). How studies of wild and captive dolphins contribute to our understanding of
individual differences and personality. International Journal of Comparative Psychology, 23, 269-277.
Hill, H. M., Kuczaj, S. A., II, Greer, T., & Solangi, M. (2007). All mothers are not the same: Maternal styles in
bottlenose dolphins Tursiops truncates. International Journal of Comparative Psychology, 20, 35-54.
Holmes, B. J., & Neil, D. T. (2012). Gift giving by wild bottlenose dolphins (Tursiops sp.) to humans at a wild
dolphin provisioning program, Tangalooma, Australia. Anthrozoos: A Multidisciplinary Journal of The
Interactions of People & Animals, 25, 397-413.
Kano, F., & Tomonaga, M. (2010). Face scanning in chimpanzees and humans: Continuity and discontinuity.
Animal Behaviour, 79, 227-235.
Krützen, M., Mann, J., Heithaus, M. R., Connor, R. C., Bejder, L., & Sherwin, W. B. (2005). Cultural transmission
of tool use in bottlenose dolphins. Proceedings of the National Academy of Sciences of the United States of
America, 102, 8939-8943.
Kuczaj, S. A., II (1982). Language play and language acquisition. In H. Reese (Ed.), Advances in child development
and behavior (197-232). New York, NY: Academic Press.
Kuczaj, S. A., II (in press). Language learning in cetaceans. In P. Brooks, V. Kempe, & J. Golsoon (Eds.),
Encyclopedia of language development. Thousand Oaks, CA: Sage.
Kuczaj, S. A., II, (1983). Crib speech and language play. New York, NY: Springer-Verlag.
Kuczaj, S. A., II, & Highfill, L. E. (2005). Dolphin play: Evidence for cooperation and culture? Behavioral and
Brain Sciences, 28, 705-706.
Kuczaj & Eskelinen 126
Kuczaj, S. A., II, Highfill, L., & Byerly, H. (2012). The importance of considering context in the assessment of
personality characteristics: Evidence from ratings of dolphin personality. International Journal of
Comparative Psychology, 25, 309-329.
Kuczaj, S. A., II, Highfill, L. E., Makecha, R. N., & Byerly, H. C. (2013). Why do dolphins smile? A comparative
perspective on dolphin emotions and emotional expressions. In S. Watanabe & S. A. Kuczaj II (Eds.),
Comparative perspectives on human and animal emotions (pp. 6386). Tokyo, Japan: Springer.
Kuczaj, S. A., II, & Horback, K. M. (2013). Play and emotions. In S. Watanabe & S. A. Kuczaj II (Eds.),
Comparative perspectives on human and animal emotions (pp. 87112), Tokyo, Japan: Springer.
Kuczaj, S. A., II, Lacinak, T., Fad, O., Trone, M., Solangi, M., & Ramos, J. (2002). Keeping environmental
enrichment enriching. International Journal of Comparative Psychology, 15, 127-137.
Kuczaj, S. A. II, & Makecha, R. (2008). The role of play in the evolution and ontogeny of contextually flexible
communication. In D. K. Oller & U. Griebel (Eds.), Evolution of communicative flexibility: Complexity,
creativity, and adaptability in human and animal communication (pp. 253-277). Cambridge, MA: The
MIT Press.
Kuczaj, S. A., II, Makecha, R., Trone, M., Paulos, R. D., & Ramos, J. A. (2006). Role of peers in cultural innovation
and cultural transmission: Evidence from the play of dolphin calves. International Journal of Comparative
Psychology, 19, 223-240.
Kuczaj, S. A., II, & Walker, R. T. (2012). Dolphin problem solving. Handbook of comparative cognition (pp.736-
756). Oxford, UK: Oxford University Press.
Kuczaj, S. A., II, Yeater, D., & Highfill, L. (2012). How selective is social learning in dolphins? International
Journal of Comparative Psychology, 25, 221-236.
Lodi, L., & Hetzel, B. (1999). Rough-toothed dolphin, Steno bredanensis, feeding behaviors in Ilha Grande Bay,
Brazil. Biociências, 7, 29-42.
Lusseau, D. (2006). Why do dolphins jump? Interpreting the behavioural repertoire of bottlenose dolphins (Tursiops
sp.) in Doubtful Sound, New Zealand. Behavioural Processes, 73, 257-265.
Mackey, A. D., Makecha, R. N., & Kuczaj, S. A., II. (2014). The development of social play in bottlenose dolphins
(Tursiops truncatus). Animal Behavior and Cognition, 1, 19-35.
Martin, P., & Caro, T. M. (1985). On the functions of play and its role in behavioral development. Advances in the
Study of Behavior, 15, 59-103.
McBride, A. F., & Hebb, D. O. (1948). Behavior of the captive bottlenose dolphin, Tursiops truncatus. Journal of
Comparative Physiological Psychology, 41, 111-123.
Miklósi, A. (1999). The ethological analysis of imitation. Biological Reviews, 74, 347-374.
Palagi, E. (2009). Adult play fighting and potential role of tail signals in ringtailed lemurs (Lemur catta). Journal of
Comparative Psychology, 123, 1-9.
Paulos, R. D., Trone, M., & Kuczaj, S. A., II (2010). Play in wild and captive cetaceans. International Journal of
Comparative Psychology, 23, 701-722.
Pellegrini, A. D. (2011). The Oxford handbook of the development of play. New York, NY: Oxford University Press.
Pellis, S. M., & Pellis, V. C. (1996). On knowing it’s only play: The role of play signals in play fighting. Aggression
and Violent Behavior, 1, 249-268.
Pellis, S. M., & Pellis, V. C. (2007). Rough-and-tumble play and the development of the social brain. Current
Directions in Psychological Science, 16, 95-98.
Pellis, S. M., & Pellis, V. C. (2009). The playful brain. Venturing the limits of neuroscience. Oxford, UK: Oneworld
Publications.
Pellis, S. M., & Pellis, V. C. (2011). To whom the play signal is directed: A study of headshaking in black-handed
spider monkeys (Ateles geoffroyi). Journal of Comparative Psychology, 125, 1-10.
Piaget, J. (1952). The origins of intelligence in children. New York, NY: Norton & Company.
Piaget, J. (1962) Plays, dreams and imitation. New York, NY: Norton.
Power, T. G. (2000). Play and exploration in children and animals. Mahwah, NJ: Erlbaum.
Rendell, L., & Whitehead, H. (2001). Culture in whales and dolphins. Behavioral and Brain Sciences, 24, 309-324.
Singer, D. G., & Singer, J. L. (1990). The house of make-believe: Children's play and the developing imagination.
Cambridge, MA: Harvard University Press.
Smeenk, C., Addink, C. M., & Richards, H. (1995). Some observations of the behaviour of wild rough-toothed
dolphins Steno bredanensis. Paper presented at the biennial meeting of the Society for Marine
Mammalogy, Orlando, FL.
Sommer, V., & Mendoza-Granados, D. (1995). Play as indicator of habitat quality: A field study of langur monkeys
(Presbytis entellus). Ethology, 99, 177-192.
Kuczaj & Eskelinen 127
Špinka, M., Newberry, R. C., & Bekoff, M. (2001). Mammalian play: Training for the unexpected. Quarterly
Review of Biology, 76, 141-168.
Sutton-Smith, B. (1980). Children's play: Some sources of play theorizing. New Directions for Child and
Adolescent Development, 1980, 1-16.
Sutton-Smith, B. (2003). Play as a parody of emotional vulnerability. Play and Culture Studies, 5, 3-18.
Sutton-Smith, B. (2011). The antipathies of play. In A. D. Pellegrini, (Ed.). The Oxford handbook of the
development of play. (pp, 110 -118). New York, NY: Oxford University Press.
Tavolga, M. C. (1966). Behavior of the bottlenose dolphin (Tursiops truncatus): Social interactions in a captive
colony. In K. S. Norris (Ed.), Whales, dolphins, and porpoises (pp. 718730). Berkeley and Los Angeles,
CA: University of California Press.
Thompson, K. V. (1996). Play-partner preferences and the function of social play in infant sable antelope,
Hippotragus niger. Animal Behaviour, 52, 1143-1155.
Trone, M., Kuczaj, S. A., II, & Solangi, M. (2005). Does participation in dolphinhuman interaction programs affect
bottlenose dolphin behaviour? Applied Animal Behaviour Science, 93, 363-374.
van Baaren, R. B., Holland, R. W., Kawakami, K., & Knippenberg, A. V. (2004). Mimicry and prosocial behavior.
Psychological Science, 15, 71-74.
Vieira, M. L., & Sartorio, R. (2002). Motivational, causal and functional analysis of play behavior in two rodent
species. Estudos de Psicologia (Natal), 7, 189-196.
Vygotsky, L. S. (1978). Mind in society: The development of higher psychological processes. Cambridge, MA:
Harvard University Press.
Weir, R. H. (1962). Language in the crib. London, UK: Mouton.
West, M. (1974). Social play in the domestic cat. American Zoologist, 14, 427-436.
Würsig, B., & Würsig, M. (1979). Behavior and ecology of the bottlenose dolphin, Tursiops truncatus, in the south
Atlantic. Fishery Bulletin, 77, 399-412.
Würsig, B., & Würsig, M. (1980). Behavior and ecology of the dusky dolphin, Lagenorhynchus obscurus, in the
South Atlantic. Fisheries Bulletin, 77, 871-890.
Yando, R., Seitz, V., & Zigler, E. (1978). Imitation: A developmental perspective. Hillsdale, NJ: Erlbaum.
... It has been suggested that young animals use object play to practice foraging behaviors (Gamble and Cristol, 2002;Kuczaj and Eskelinen, 2014;Pellis et al., 2019b). If this is the case, immature animals should engage in more varied play in order to maximize their opportunities to practice these behaviors in novel contexts. ...
... One common explanation for object play in immature animals is that play with objects practices foraging techniques (Gamble and Cristol, 2002;Kuczaj and Eskelinen, 2014;Pellis et al., 2019b), thus, object play is serving a delayed benefit. However, adults, who do not need to practice adult behaviors, also engage in object play. ...
Thesis
Although many species of Cetacea play, few detailed studies of their play exist. The present thesis provides detailed descriptions of two types of social play (sexual play and mouth-to-mouth interaction play) and one type of non-social play (object play) in belugas (Delphinapterus leucas), an Artic dwelling species of toothed whale. The group studied contained animals of many ages of both sexes and was maintained under human care. Given the unique features of different types of play, a major conclusion of this thesis is that play is multi-functional. Indeed, even a single form of play (e.g., mouth-to-mouth interactions) may have more than one function. For example, while mouth-to-mouth interactions may help train motor coordination skills in immature animals, such play may be used to form and maintain social relationships in adults. For belugas, play is serving many functions, all depending on the type of play and the age of the animals.
... During PSO, we provided dolphins with only objects of high interest. Indeed, although dolphins are frequently observed to use different types of objects (Green et al., 2011;Kuczaj & Eskelinen, 2014), they have their own preferences, and some objects arouse more interest than others (Delfour, Faulkner, & Carter, 2017;Neto, Silveira, & Dos Santos, 2016). Therefore, as the intensity of anticipatory behavior is related to the animal's interest in the event (Clegg et al., 2018), according to another study, we used only the most interesting objects (Clegg et al., 2018). ...
Article
Anticipatory behavior describes the actions taken to prepare for an upcoming event. It is considered a promising tool for welfare assessment, but it is not fully applied in zoos and other facilities. This is probably due to the need to train animals, which can take a long time and make its use impractical. In this work, we tested, on a group of six dolphins (Tursiops truncatus), the effectiveness of a new technique to induce and measure anticipatory behavior without training animals. Our results show how this new methodology, which we called The Fast Technique (TFT), has been able to induce and measure anticipatory behavior toward the event studied, i.e., the play sessions with objects (PSO). Furthermore, it has produced the same result obtained with The Classical Technique (TCT), which requires a training phase. Therefore, our finding demonstrates the efficacy of a new technique that could facilitate the use of anticipatory behavior for both research and animal welfare assessment protocols.
... Alliance formation plays a crucial part in male dolphins' life; male dolphins cooperate for the primary purpose of gaining and/or maintaining access to females (e.g., Connor et al. 1992bConnor et al. , 1999Connor et al. , 2017. However, as part of group living, affiliative relationships provide additional advantages, such as participation in cooperative hunting (e.g., Benoit-Bird and Au 2009; Engleby and Powell 2019; Gazda et al. 2005;Jiménez and Alava 2015;Silber and Fertl 1995;Torres and Read 2009), social learning (Bender et al. 2009;Kuczaj et al. 2012;Mann et al. 2007) or social play (Ikeda et al. 2018;Kuczaj and Eskelinen 2014;Mackey et al. 2014). As a result, bottlenose dolphins have been described to have the most complex social structure outside of humans (Connor et al. 1992a(Connor et al. , 1999. ...
Article
Full-text available
Alliance formation plays a crucial part in male dolphins’ lives. These partnerships may last for decades or even for a lifetime; thus, partner choice and the maintenance of these relationships are both considered key components of alliance formation. In our previous investigations, pairs of adult male dolphins showed a high success rate in cooperative manipulation of a cognitive enrichment device. Here, we introduced two novel cognitive enrichment devices to the group of five dolphins, facilitating simultaneous actions for not only pairs, but for three or even four dolphins. The devices were made of PVC tubes, fittings and caps equipped with rope handles, creating a three-way (T-shape) and a four-way (TT-shape) device. The devices were filled with fish and ice and were designed to be opened by simultaneous pull of the handles. Both devices were tested in 12 trials (each lasted for 15 min), separately. Only one of the caps could be opened, the others were affixed with the position of the openable cap counter-balanced over the trials. Although the dolphins received no training regarding the manipulation of the devices, they were successful in cooperatively opening the three-way devices in 10/12 of trials (70% by two and 30% by three dolphins) and the four-way devices also in 10/12 trials (50% by two, 40% by three and 10% by four dolphins). The dolphins interacted with the devices during the entire testing time, and this was mostly spent in cooperative play (77% and 56% of the test duration with the three-way and four-way device, respectively). The majority of the cooperative play was observed between one particular pair of dolphins that was temporarily associated with a third or sometimes even with a fourth dolphin. These findings demonstrate the first successful use of multi-partner cooperative enrichment devices, providing information on the social organisation of a male dolphin group.
... This study supports the evidence that plastic debris is one of the main threats affecting cetacean species [127] as well as the biodiversity of the entire Mediterranean basin in general [128,129]. Although the reason for the interaction between Risso's dolphins and other cetacean species and plastic debris remains unclear, it may be related to the investigation of inappropriate prey items due to debilitation or starvation [47,130] or as play, as observed for free-ranging rough-toothed dolphin (Steno bredanensis) and estuarine dolphin (Sotalia fluviatilis), as well as for common bottlenose dolphin in captivity [131]. Although the magnitude of the effect of this problem on dolphin and whale species is not yet known, the implementation of concrete action to mitigate impacts of harmful anthropogenic threats (i.e., plastic debris release at sea) is urgent. ...
Article
Full-text available
Relatively scant information is available on the Risso’s dolphin in comparison to the other species regularly present in the Mediterranean Sea. Recently, its conservation status has been updated to Endangered by the International Union for Conservation of Nature (IUCN) in this Sea. Therefore, the need to increase information on its biology and ecology is even more urgent. This study reports the first preliminary information on the behavioral traits of the species occurring in the Gulf of Taranto (Northern Ionian Sea). Data on predominant behavioral activity states and on a set of group composition variables (group formation, cruising speed, dive duration and interaction between individuals) were collected from April 2019 to September 2021, applying the focal-group protocol with instantaneous scan sampling. Group size, depth and group composition variables were compared between activity states. Results highlight that both the group size and the several variables considered varied significantly depending on activity state. The group size was significantly smaller during feeding than resting and traveling and a characterization in terms of group formation, cruise speed, dive duration and interaction between animals is provided for the different activity states. Moreover, a list of behavioral events which occurred, as well as their relative frequency of distribution among activity states, is reported. Finally, details on the sympatric occurrences between Risso’s and striped dolphins, as well as the repetitive interaction observed between adult individuals and plastic bags floating on the sea surface, are reported and discussed.
... Non-human animals engage in play(ful) behavior [110][111][112][113][114][115], but only humans play rule-based games [112]. Rule-based games are more than just child's play. ...
Article
Full-text available
While most animals play, only humans play games. As animal play serves to teach offspring important life-skills in a safe scenario, human games might, in similar ways, teach important culturally relevant skills. Humans in all cultures play games; however, it is not clear whether variation in the characteristics of games across cultural groups is related to group-level attributes. Here we investigate specifically whether the cooperativeness of games covaries with socio-ecological differences across cultural groups. We hypothesize that cultural groups that engage in frequent inter-group conflict, cooperative sustenance acquisition, or that have less stratified social structures, might more frequently play cooperative games as compared to groups that do not share these characteristics. To test these hypotheses, we gathered data from the ethnographic record on 25 ethnolinguistic groups in the Austronesian language family. We show that cultural groups with higher levels of inter-group conflict and cooperative land-based hunting play cooperative games more frequently than other groups. Additionally, cultural groups with higher levels of intra-group conflict play competitive games more frequently than other groups. These findings indicate that games are not randomly distributed among cultures, but rather relate to the socio-ecological settings of the cultural groups that practice them. We argue that games serve as training grounds for group-specific norms and values and thereby have an important function in enculturation during childhood. Moreover, games might server an important role in the maintenance of cultural diversity.
... Age may also influence an individual's activities. For example, younger dolphins under professional care engage in more play behavior while older animals engage in more low intensity swimming [54]. ...
Article
Full-text available
Cetaceans are long-lived, social species that are valued as ambassadors inspiring the public to engage in conservation action. Under professional care, they are critical partners with the scientific community to understanding the biology, behavior, physiology, health, and welfare requirements of this taxonomic group. The Cetacean Welfare Study was a highly collaborative research effort among zoos and aquariums accredited by the Alliance for Marine Mammal Parks and Aquariums and/or the Association of Zoos & Aquariums that provided important empirical and comparative information on the care and management of cetaceans. The goal was to identify factors that were related to the welfare of bottlenose dolphins and to develop reference intervals and values for common and novel indicators of health and welfare for common bottlenose dolphins ( Tursiops truncatus ), Indo-Pacific bottlenose dolphins ( Tursiops aduncus ), beluga whales ( Delphinapterus leucas ), and Pacific white-sided dolphins ( Lagenorhynchus obliquidens ). Data were collected from cetaceans at 43 accredited zoos and aquariums in seven countries in 2018 and 2019. This overview presents a summary of findings from the initial research articles that resulted from the study titled “Towards understanding the welfare of cetaceans in zoos and aquariums.” With multiple related objectives, animal-based metrics were used to advance frameworks of clinical care and target key conditions that were associated with good welfare of cetaceans in zoo and aquarium environments. As a result of this collaboration, species-specific reference intervals and values for blood variables and fecal hormone metabolites were developed and are freely available in an iOS application called ZooPhysioTrak. The results suggested that environmental enrichment programs and social management factors were more strongly related to behaviors likely indicative of positive welfare than habitat characteristics for common and Indo-Pacific bottlenose dolphins. These findings can be widely applied to optimize care and future science-based welfare practice.
Article
All mammals experience different life stages as they develop, each of which is characterised by particular physical and behavioural changes. Despite the emergence of sophisticated behaviour analysis techniques, the ways in which social behaviour varies by life stage, and how this is influenced by an individual’s sex, is relatively understudied in most social mammals other than primates and elephants. Understanding the social requirements of mammals should be a central and critical component to their conservation, captive management and welfare. Here, we apply social network analysis techniques to understand how social behaviour differs with life stage in the giraffe, a gregarious fission–fusion mammal. We studied two wild populations of giraffes in Kenya and found that adolescents have significantly stronger associations with adolescents of their own sex first and foremost, then adults of their own sex. Other associations were significantly lower than would be expected, or non-significant. Our results suggest that adolescence in both male and female giraffes shares similar features to adolescence in other social mammal species. We discuss how the application of such knowledge might improve the management and welfare of captive giraffes.
Article
This is the second part of a two-part article presenting the theoretical and empirical case for nonhuman animal (hereafter, ‘animal’) spirituality. Part 1 discussed the relevance of evolutionary theory and species differences for understanding animals’ capacity to have spiritual experience, conceptual issues related to defining animal spirituality, and methodological considerations regarding analogical reasoning and animal-centered anthropomorphism as heuristic strategies in the study of animal spirituality. Issues related to the question of animal consciousness and the use of evolutionary panentheism as a philosophical/theological frame for theorizing about animal spirituality were discussed. Part 2 examines six biopsychosocial capabilities of animals that are building blocks of human spirituality—cognition, imagination, emotion, moral sense, personality, and value-life (Maslow’s phrase)—and proposes an ontic pluralism of animal spiritualities. Part 2 concludes with a discussion of the wide-ranging implications for human society of consciously accepting the possibility of animal spirituality and capacity to have spiritual experience.
Article
Food provisioning promotes close interaction with wildlife but can negatively impact the targeted species. Repeated behavioural disruptions have the potential to negatively impact vital rates and have population level consequences. In Bunbury, Western Australia, food-provisioned female bottlenose dolphins, Tursiops aduncus, suffer reduced reproductive success via lower calf survival. However, the proximal causes of this long-term negative effect remain unknown. To infer processes that could lead to fitness costs, we combined network analyses, Markov Chain, regression models and kernel density estimates to evaluate the social environment, behavioural budget and home range size of provisioned dolphins relative to their nonprovisioned counterparts. We found that provisioned dolphins spent significantly less time socializing and had smaller home ranges and weaker social associations than the nonprovisioned dolphins. Overall, these findings suggest that provisioned dolphins experience a more restricted social environment among themselves, which likely results from investing time in an unnatural foraging tactic around the provisioning site, in proximity to human activities. This modified social environment associated with food provisioning and begging behaviour, reinforced by the limited time spent socializing, could affect the opportunities of calves of provisioned females to acquire fitness-enhancing skills and form essential social bonds. This study highlights the need to consider the potential impact of human activities on the social environment of animals.
Article
Intoxications of captive bottlenose dolphins (Tursiops truncatus) in the Florida Keys have been linked to observed interactions with marine macrophytic algal and cyanobacterial communities within enclosures. Taxonomic characterization of these communities coupled, in turn, to available observational data collected during intoxication events point to a contribution of filamentous cyanobacterial assemblages comprised of members of the polyphyletic genus, Lyngbya sensu lato. To identify toxic metabolites possibly relevant to these intoxications, chemical screening for known neurotoxins from cyanobacteria, as well as other regionally relevant harmful algal bloom (HAB) taxa, was combined with toxicity testing, and subsequent bioassay-guided fractionation, employing early life stages (i.e., embryos and larvae) of zebrafish (Danio rerio) as a well-established aquatic vertebrate toxicological model. Chemical analyses did not detect (within analytical limits) any of the known algal or cyanobacterial neurotoxins. Toxicity testing, alongside bioassay-guided fractionation, however, identified several chemical fractions with a range of potentially relevant bioactivities in both zebrafish embryos and post-hatch larvae including, in particular, behavioral (e.g., aberrant swimming) and physiological (e.g., altered heart rate) endpoints indicative of possible neurotoxicity, and subsequent chemical characterization of fractions suggested a contribution of the previously identified bioactive metabolite, eudesmacarbonate, in the observed toxicity. Comparative toxicological assessment with PbTx-2, as a positive control for neurotoxicity in the zebrafish model, further supported neurotoxic activity of cyanobacterial metabolites potentially relevant, in turn, to a contribution of these metabolites to dolphin intoxications. These findings suggest, in general, that marine zoological facilities may be affected by regional HABs, and assessments of potentially toxigenic algae and cyanobacteria should be included in management strategies in these facilities.
Book
The role of play in human development has long been the subject of controversy. Despite being championed by many of the foremost scholars of the twentieth century, play has been dogged by underrepresentation and marginalization in literature across the scientific disciplines. The Oxford Handbook of the Development of Play attempts to examine the development of children's play through a rigorous and multidisciplinary approach. This book aims to reset the landscape of developmental science and makes a compelling case for the benefits of play.