Chap.05 Cultural Transmission 鄭先祐 (Ayo) 教授 國立台南大學 環境與生態學院 生態科學與技術學系 環境生態研究所 + 生態旅遊研究所

Ayo 2010 Ethology2 Cultural transmission  What is cultural transmission?  Models of cultural transmission  Vertical  Horizontal  oblique  The interaction of genetic and cultural transmission  Cultural transmission and brain size

Ayo 2010 Ethology3 What is cultural transmission?  The transfer of information from individual to individual through social learning or teaching– both within and between generations of animals.  Japanese macaque monkey in Koshima islet. (potato washing) (Fig. 5.1, 5.2)

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5 Glance-6476 (female macaque)  Stone play behavior (Fig. 5.3) was first observed in 1979 when Glance-6476, a three-year-old female macaque, brought rocks in from the forest and started stacking them up and knocking them down.  Four years later, stone play had already become a daily occurrence and was already being transmitted from older to younger individuals.  Cultural transmission seems to work down the age ladder, but not up (Fig. 5.4)

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7 Orange bars represent verified stone handlers, and green bars represent individuals not verified as stone handlers.

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10 What is cultural transmission?  As a system of information transfer that affects an individual’s phenotype by means of either teaching or some form of social learning.

Ayo 2010 Ethology11 The child is learning to use utensils by watching others. The chimp also has learned his nut-cracking skills from watching others.

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Ayo 2010 Ethology14 What’s so important?  Cultural transmission involves the spread of information from individual to individual (Fig. 5.7, 5.8)  And may be passed down through endless generations.  Cultural transmission can occur within a population very quickly.  Operates much faster, and can easily cause important changes in the behavior.  比透過演化改變，還要快很多。 (Fig. 5.9)

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Ayo 2010 Ethology16 Effects of others on behavior  Cultural transmission relies in one sense or another on a “model” individual (also called a demonstrator or tutor) and an “observer”, who learns a specific behavior or response form the model (Fig. 5.10)  Local enhancement  Social facilitation

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Ayo 2010 Ethology18 Local enhancement and social facilitation  Local enhancement, individuals learn from others, not so much by doing what they observe, as by being drawn to a particular area because another individual (a model) was in that location. (Fig. 5.11)  Social facilitation, the mere presence of a model, regardless of what he does, is thought facilitate learning on the part of an observer. (Fig. 5.12)  Safety in numbers

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Ayo 2010 Ethology21 Local enhancement and social facilitation  Capuchin monkeys (Fig. 5.13)  Three treatment (Fig. 5.14)  Alone  Group present  Group plus food

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Ayo 2010 Ethology23 Social facilitation Local enhancement

Ayo 2010 Ethology24 Social learning  Social learning is sometime referred to as “observational learning” in the psychology literature. (Fig. 5.15)  “bobo” doll study, a classic example. (Fig. 5.16)  In Bandura ’ s classical bobo doll experiments, the power of social learning is frighteningly evident, as young children treated the bobo doll as aggressively as the adult they observed.

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Ayo 2010 Ethology27 Imitation  Imitation involves the “acquisition of a topographically novel response through observation of a demonstrator making that response.  An observer bird watches a trained pigeon who must lift its foot and push on a lever to open a small circular entrance to a food source. (Fig. 5.17)  Blue tit birds learned to peck open the top of milk jugs decades ago. (cultural transmission) (Fig. 5.18)

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Ayo 2010 Ethology30 Copying  When animals copy one another, an observer repeats what he has see a model do.  Copying differs from imitation in that what is copied need not be novel and need not involve learning some new topographical action.  Mate-choice copying in the guppy fish. (Fig. 5.19)  Copying a defensive response (Fig. 5.20)

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Ayo 2010 Ethology32 After a mouse is bitten by stable flies, one of its defensive responses is to bury itself under debris. A mouse that observes another mouse being bitten by a stable fly and then hiding will copy the hiding behavior of the model mouse as soon as it is exposed to a fly.

Ayo 2010 Ethology33 Teaching in animals  Given the complexity that we associate with teaching.  Cheetah teaching, (A) a mother cheetah brings a Thomson ’ s gazelle to her cubs, and allows them to “ kill it ”, even though it was already dead. (B) until the young cheetah is taught how to hunt, it can only kill small items like the hare shown here (Fig. 5.21)  Meerkat forging and teaching (catch scorpions) (Fig. 5.22)

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Ayo 2010 Ethology36 Modes of cultural transmission  Vertical, horizontal, and oblique transmission (Fig. 5.23)  In vertical transmission systems (panel 1), information is passed from parent to child.  When horizontal transmission (panel 2) is in operation, an individual learns from peers.  In oblique transmission (panel 3), young individuals learn from adults who are not their parents.

Ayo 2010 Ethology37 vertical transmissionhorizontal transmission oblique transmission

Ayo 2010 Ethology38 In some finch species, vertical transmission is taking place when males learn the song that they will sing from their fathers, and when females develop song preferences in potential mates based on the songs their father sang.

Ayo 2010 Ethology39 Fig Dolphins may trap fish by stranding them on a beach and then surging out of the water to catch them. (vertical transmission)

Ayo 2010 Ethology40 Fig Female bottlenose dolphins break a marine sponge off the seafloor and place it over their mouth. This tool is used to probe the seafloor for fish prey and to protect them from scrapes and stings as they forage. (vertical transmission)

Ayo 2010 Ethology41 Horizontal cultural transmission  Horizontal transmission: in humans, everyday experiences of demonstrate that most information comes from peers, people who are of the same approximate age group.  Foraging-related information in guppies  Once the “ long-path ” and “ short-path ” groups were trained. 逐步的移除受訓者，讓未受訓者自己 找路。  Both the short-path and long-path groups, guppies 都可學習到找到路線。  但如此的 cultural transmission can produce ” maladaptive ” (long-path use) as well as adaptive (short-path use) behavior.

Ayo 2010 Ethology42 Oblique cultural transmission  Oblique transmission has been uncovered in many scenarios, such as predator recognition in blackbirds.  Learned snake aversion in rhesus monkeys.  Rhesus monkeys in the field often fear snakes after watching others respond to such potential danger.  Monkey raised in the lab, who do not normally fear snakes, can be made to fear them through observing older monkeys reacting fearfully to snakes. Young monkeys were shown this video of an older monkey who fled to the back of the cage and cringed in fear at the sight of two snakes.

Ayo 2010 Ethology43 Fig. 5.27

Ayo 2010 Ethology44 The interaction of genetic  The Grants finches (Darwin finches)  The ground finch and the cactus finch, no fitness penalty for hybridization.  But rarely interbreed, why?  Cultural transmission play a role in inhibiting such a merger (interbreed). Male songs were transmitted across generations via cultural transmission (Fig. 5.28)  Guppy mat choice

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Ayo 2010 Ethology47 Guppy mate choice  Female guppies copy the mate choice of other females.  In this type of cultural transmission of information, genetic transmission of traits also plays an important role in guppy mate-choice behavior.

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Ayo 2010 Ethology49 Cultural transmission and brain size

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