PSYO 2160 Lecture Notes - Lecture 16: Marc Bekoff, Bighorn Sheep, Kinematics
3 May 2018
School
Department
Course
Professor
Play
November 23, 2015
*Do not read “A phylogenetic approach to play”
read “Interview with Marc Bekoff” and the Waller&Cherry 2012 study
• “animals don’t play”
• argued that play is just behaviours we don’t understand
• Ethologists concerned with function of behaviours
o Why do animals play? Natural section/survival/reproduction
o How or under what conditions has play been selected for
• Playing is extremely costly
o Harcourt (1991): fur seals, 6% time spent playing
▪ 22/26 pups killed were engaged in play at time of being killed
o If all mammals play there must be a benefit
• Function of play is different for different species
o Different individuals of the same species (age, sex – different play)
o A heterogenous category linked together by characteristics that may be superficially similar, have
separate origins, causes, functions and ontogenies” (Burg.)
• “No behavioural concept have been proved more ill-defined, elusive, controversial and even unfashionavle
than play” (E.O. Wilson)
Mark Bekoff
• Argues the study of play from an ethological standpoint is worthwhile
1. Cross-species show similarities in play
• Simpliest explanation is the best one - parsimonious
2. Because all mammals play, there must be some phylogenetic reason with benefits from play
• In order to study play there must be theory and function
• Function of Play:
o Play enables animals to develop flexible kinematic and emotional response to unexpected events I
which the experience a sudden loss of control
o Play functions to increase the versatility of movements used to recover from sudden shocks
allowing them to cope emotionally with unexpected stressful situations
• Hypotheses for Function of Play
o 24 hypotheses
o Functional consequences, kinematics and structure, social aspects, neuropsychological
mechanisms, environmental conditions, ontogenetic distribution, phylogenetic distribution
• Definition of Play:
o Play is a motor activity performed postnatally that appears to be purposeless, in which motor
patterns from other contexts may often be used in modified forms and alters temporal sequencing.
If the activity is directed towards another it is called social play.
• Purposeless?
o Observed fails to decipher purpose
o Purpose and benefit may not be accrued until long after play has occurred
o May have multiple benefits and are confounding (immediately observable)
• Characteristics of Play:
o More repetitious or exaggerated behaviours than seen in ordinary activities
o Movements may look incomplete compared to normal species action patterns
o May be elicited by a wide variety of different stimuli
• More Characters of Play:
o Typically seen in juvenile mammals during “socialization period” – not responsible for own well
being
o Play accounts for less than 10% of total time and energy budget – more common in captive
animals
find more resources at oneclass.com
find more resources at oneclass.com
o Ex. When turtle would “play” the frequency of self-harming incidents decreasesd
Types of Play:
• Object Play
o Use on inanimate objects
o Differs from object exploration (actually uses object)
o Ex. Gorillas playing in leaves
o Ex. Object Play in Ravens
▪ Observed 4 juvenile Raven’s behaviour towards naturally occurring objects
▪ Added 44 “novel” items
▪ Approached all objects
▪ Objects associated with food – ravens spent more time with these objects
o Function of Object play: learn from object that helps them in long or short term
• Locomotor Play
o Running, chasing, stalking, jumping, head shakes…etc.
o Ex. Goats
o Functions:
1. Exercise and development of specific motor skills needed later in life
2. Provides animals with a better understanding of their surroundings
o Increases the creation of synapses in cerebellum
▪ Cerebellum is important for coordination, balance
o Ex. Play is highest in mice when cerebellar synaptogenesis in also the highest *cats at ~10days
• Social Play
o Playing with others
o Ex. Baby Gorillas play when the mother is looking for food
o Functions:
1. May lead to formation of long lasting social bond
2. May promote and fine-tune physical skills
3. May aid development of cognitive skills
o Functions of Social Play - in Bighorn sheep for competition between males for access to females
▪ Can fine tune physical skills
▪ Juvenile males engaged in much more contact than feamles
▪ “Play markers” – shake head
▪ Play does not begin at a certain age
▪ Play tapered off more quickly in desert populations (tend to run into cacti)
o Cognition
▪ “self assessment” – how strong the individual is
▪ How do animals know they’re playing?
• The order and frequency of behaviour patterns are different from “real world”
activities – ex. Biting differently in hunting than play
▪ Play markers
• Signals that serve to initiate play, creating a desire to continue playing
• Ex. Play bows in dogs so other dogs do not think the other one is being
aggressive
• Suggests that behaviour could be taken a different way
▪ E.g. Gorilla “play face”
• Two different forms: lower extended with bottom teeth showing OR with top
teeth showing
• No teeth showing – happy
• Laughing – bottom teeth
▪ Role Reversal
• Dominant individuals do not try to intimidate or immobilize subordinate animals
but act in a way that doesn’t represent normal aggressive behaviour
▪ E.g. Squirrel monkeys may accept a dominant play partner
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
*do not read a phylogenetic approach to play . Read interview with marc bekoff and the waller&cherry 2012 study. Natural section/survival/reproduction: how or under what conditions has play been selected for, playing is extremely costly, harcourt (1991): fur seals, 6% time spent playing. 22/26 pups killed were engaged in play at time of being killed. No behavioural concept have been proved more ill-defined, elusive, controversial and even unfashionavle than play (e. o. When turtle would play the frequency of self-harming incidents decreasesd. Types of play: object play, use on inanimate objects, differs from object exploration (actually uses object, ex. Goats: functions, exercise and development of specific motor skills needed later in life, provides animals with a better understanding of their surroundings. Increases the creation of synapses in cerebellum: cerebellum is important for coordination, balance, ex. Play is highest in mice when cerebellar synaptogenesis in also the highest *cats at ~10days: social play, playing with others, ex.
