biological knowledge harry purser h.purser@kingston.ac.uk

Biological Knowledge

Harry Purser

h.purser@kingston.ac.uk

Why is it useful to study children’s conception of biology?

• Help design classroom science• Aid in development of science-related museum

exhibits• Informs us about role of developmental theory • Contributes to knowledge of what children learn

from interactions with more advanced others

Points to consider

• What constitutes having a theory of biology?• What types of knowledge should children

have to demonstrate before being credited with such a theory?

• How do children acquire this theory?

Hatano and Inagaki (1994)

• Distinction between non-living and living things/mind and body

• Model of inference to predict attributes or behaviours of living things

• Non-intentional explanatory framework for behaviours relevant to biological processes

• Conceptual Devices

• Distinction between living and non-living

Piaget (1929)

Stage

No understanding

Life based on activity Washing machine

Life based on movement Cars

Autonomous movement Clouds

Correct Animals and animals and plants

Living thingsINV: Max, can you tell me, is a cloud a living thing?CHI: Nope.INV: Why not?CHI: Because it doesn’t. Because it doesn’t walk.INV: Does a cloud breathe?CHI: No.INV: Does it feed?CHI: No.INV: Does it grow?CHI: No.INV: Is a person a living thing?CHI: What?INV: Is a person a living thing?INV: Like a person like you. Are you a living thing?CHI: Nods yes.INV: Yeah. Why?CHI: Because I breathe.INV: So people breathe?INV: Do people feed?INV: Do they grow?INV: What about a rock? Is a rock a living thing?CHI: No.INV: Why not?CHI: Because it doesn’t grow.

Hatano, Siegler, et al., 1993

• People• Other animals• Plants• Inanimate

• Being a living thing

Hatano, Siegler, et al., 1993

• Japan, US, Israel• K, 2, 4th graders

Hatano, Siegler, et al., 1993

• By K, most children know people and animals are alive

• 60% of Israeli 4th graders judge plants not be alive

• 8% of Japanese 4th graders think that inanimate objects are alive

• Model of inference to predict attributes or behaviours of living things

Carey (1985)

• Comes from folk psychology• Psychological confusion (intentional causality

b/c ignorant of physiological mechanisms)• Death

Carey (1985)

• Projection task to other animals– Humans– Dogs

• 4 yr : people to dogs (75%)

• Dogs to people (20%)• 10 yr: Humans not

central

• Nonintentional causal framework

Inagaki & Hatano (1993)

• Why do we take in air?– 4: Feel good (intentional)– 6: Chest takes in vital power from the air (vitalistic)– 8 and adults: Lungs take in oxygen and turn it into

carbon dioxide (mechanical)

Kelemen (1999)

• Teleogical thinking: objects and living things exist for a purpose

• Why did Cryptoclidus have a long neck? Why are rocks pointy?

• So that they wouldn’t get smashed• So that Cryptoclidus could scratch his neck• Because bits of stuff piled up on them for a

long time

Teleological Explanations

• Living things: adults and children use teleological reasoning for living things

• Natural Kinds: 7/8 yr children use teleological reasoning rather than physical-reductionist explanations for (non-living) natural kinds: ‘promiscuous teleology’

Johnson and Carey (1998)Predicted a dissociation between general knowledge of animals (e.g., number of legs, what it eats, where it lives) andcore folk-biological concepts (e.g., determinantsof species identity, the notion that humans areone animal of many).

WS = 12-yr-old TD, matched on language knowledge, on biological general knowledge

WS = 6-yr-old TD on folk-biological concepts

WS group had not acquired folk-biological conceptsappropriate for VMA, even though the requisite generalknowledge was probably in place: not just about knowledge!

How do children develop theories in these core conceptual domains?

• Nativists (Spelke): they are innate

• Theory theory (Gopnik): children construct theories

• Socioculturalists (Callanan & Oakes): children learn from others

Early Theories: Core Cognitive Domains

Folk Psychology Folk Biology Folk Physics

Conceptual Categories

• Babies (7 months) treated plastic toy birds and airplanes, which are perceptually similar, as if they were members of the same category

• Babies (9 -11 months) treated toy airplanes and birds as members of conceptually different categories, despite the fact that they looked very much alike

Mandler & McDonough, 1993

Biology (Rosengren, Gelman, Kalish, & McCormick, 1991)

• This is my friend, Sharon. When she is an adult, what will she look like?

Rosengren, Gelman, Kalish, & McCormick, 1991

This is my frog. What will it look like when it is an adult?

Rosengren, Gelman, Kalish, & McCormick, 1991

• This is my light bulb. If I kept it in a box for a long time, what would it look like?

Biology (Rosengren, Gelman, Kalish, & McCormick, 1991)

• Children as young as 3 picked bigger objects for animals

• More frequently than adults, 3 year olds picked picture of larger artifact

• 5 year olds resembled adults

Lack of conceptual devices: evolution

• Evans (2001)• How do things get here?• Spontaneous generation, evolution,

creationism

Trees

A long, long time ago there were no things on earth. Then there were the first trees ever. How do you think the first tree got here?

Trees

A) It came from someplace else.

B) God made it.C) It changed from a

different kind of plant that used to be on earth.

What children said…

7: creationist and spontaneous generation> evolutionary

9: creationist> evolution11: equal creationism

and evolution

Body vs MindInagaki & Hatano (2002):

When playing with a child who has a cold and is coughing a lot, who is more likely to catch cold?Boy A - often hits and pinches his friend on the back but eats a lot at meals every day

Boy B, who is a good friend but eats only a little?’’

5-year-olds choose boy B, weighting the biological/physical cue (e.g., insufficient nutrients) more heavily than the psychological/moral cue

Hood, Gjersoe & Bloom (2012)

- Demonstrate duplicating device

- Introduce hamster with 3 invisible physical properties (marble in stomach, blue heart, broken back tooth) and 3 mental states (tell it child's name, show a drawing by child, child tickles hamster)

- ‘Duplicate’ hamster

- Ask child whether duplicated hamster has these properties/states

Hood, Gjersoe & Bloom (2012)

- Much more likely to attribute same physical properties

- No such bias when a video-camera is duplicated

- Stronger bias when attention drawn to unique identity of the first hamster by giving it a name

- Notions of unique individuals and mind body dualism are present in 5-to-6-year-old children even though it is unlikely they have been explicitly tutored in these philosophical issues