Adults representations of the Earth: Implications for children s acquisition of scientific concepts. Gavin Nobes Georgia Panagiotaki

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1 Adults representations of the Earth: Implications for children s acquisition of scientific concepts Gavin Nobes Georgia Panagiotaki University of East Anglia Address for correspondence: Gavin Nobes, School of Social Work and Psychosocial Sciences, University of East Anglia, Norwich, NR4 7TJ, UK. g.nobes@uea.ac.uk Acknowledgements: We would like to thank students at the University of East London and Newham College of Further Education for their participation in this study. Thanks also to Katharina Dworzynski, Alan Martin, Anita Potton, Herjit Seetal and Natalie Yates for their help with data collection and coding. This research was supported by a grant to the authors from the Economic and Social Research Council (RES ). 1

2 Abstract When children are asked to draw the Earth they often produce intriguing pictures in which, for example, people seem to be standing on a flat disc or inside a hollow sphere. These drawings, and children s answers to questions, have been interpreted as indicating that children construct naïve, theory-like mental models of the Earth (e.g., Vosniadou & Brewer, 1992). However, recent studies using different methods have found little or no evidence of these mental models, and report that many young children have some scientific knowledge of the Earth. To examine the reasons for these contrasting findings, adults (N = 350) were given the drawing task previously given to 5-year-old children. Fewer than half of the adults pictures were scientific, and 15% were identical to children s naïve drawings. Up to half of the answers to questions (e.g., Where do people live? ) were non-scientific. Open-ended questions and follow-up interviews revealed that non-scientific responses were given because adults found the apparently simple task confusing and challenging. Since children very probably find it even more difficult, these findings indicate that children s non-scientific responses, like adults, often result from methodological problems with the task. These results therefore explain the discrepant findings of previous research, and support the studies that indicate that children do not have naïve mental models of the Earth. 2

3 Adults representations of the Earth: Implications for children s acquisition of scientific concepts Investigation of children's understanding of the Earth provides insights into some key issues in conceptual development, such as the origins of scientific knowledge and the structure and content of emerging concepts. This is because a number of aspects of the Earth contradict everyday observations (e.g., it is spherical) and are counterintuitive (e.g., people can live in Australia without falling off). If at first children think that the Earth is shaped like a disc, they must base their views on their own observations and intuitions: it is unlikely that they will have been taught that it is flat. On the other hand, if the first belief about the Earth s shape is that it is round, this scientific information must have been acquired from cultural sources such as school or the media. Most researchers in this field have asked children to represent their beliefs by drawing the Earth (e.g., Hayes, Goodhew, Heit & Gillan, 2003; Nussbaum & Novak, 1976; Sneider & Pulos, 1983; Vosniadou & Brewer, 1992). Young children tend to produce intriguing pictures, in particular the so-called flat Earth, which is an extended plane with people living only on top; the hollow sphere, with people living inside; and the dual Earth with one flat Earth on which we live, and another round one in the sky. These drawings have been reported in a number of cultures (e.g., Brewer, Hendrich & Vosniadou, 1987; Diakidoy, Vosniadou & Hawks, 1997; Vosniadou, 1994; Vosniadou & Brewer, 1990), and resemble the models that children make when given clay or play-dough to represent the Earth (Samarapungavan, Vosniadou & Brewer, 1996; Vosniadou, Skopeliti & Ikospentaki, 2004). Moreover, when these researchers have asked questions about various properties of the Earth, children often say, for example, that people live on top or inside, and that the Earth has an edge from which we can fall. 3

4 Vosniadou and her colleagues claim that these drawings, models and answers show that young children s beliefs about the earth are based more on their own observations (e.g., that the local environment is flat), and intuitions or constraints (e.g., that unsupported objects fall), than on cultural information. In addition, these researchers propose that children s beliefs about the earth are organized and coherent: they have theory-like mental models. At first, their initial mental models are of the flat earth. Later, in response to increasing exposure to cultural influences, they form synthetic models - such as the hollow and dual earths - which combine their intuitions that the earth is flat with the scientific information that it is round. According to the mental model theorists, the scientific model is only acquired in late childhood when constraints and resistance to instruction are overcome. The mental model account of children s conceptions of the earth is consistent with theory theory (e.g., Brewer & Samarapungavan, 1991; Carey, 1985; Gopnik, 2005; Wellman & Gelman, 1998), according to which cognitive development involves processes of radical conceptual change. It is suggested that, in this domain and others such as biology, maths and physics, children have conceptual revolutions that resemble those that occur in the history of science. For example, the development of children's conceptions of the earth from initial, through synthetic, to scientific, is said to be closely analogous to the historical shifts from the ancient flat earth view, through Ptolemy's geocentric theory, to the Copernican revolution (Gellatly, 1997; Vosniadou & Brewer, 1992; Vosniadou, 1994). This account has been criticized in a number of recent studies that have found little or no evidence of naïve mental models of the earth. These have also reported that young children know considerably more especially that the earth is spherical than the mental model theorists have claimed. The recent studies have used different methods from the drawing and model-making tasks favoured by the mental model theorists: children have been asked to choose between a number of 3D models (Martin, 2006; Nobes, Moore, Martin, Clifford, 4

5 Butterworth, Panagiotaki & Siegal, 2003; Panagiotaki, Nobes & Banerjee, 2006a; Siegal, Butterworth & Newcombe, 2004) or pictures (Nobes, Martin & Panagiotaki, 2005; Straatemeier, van der Maas & Jansen, 2006), or have been interviewed with reference to a globe (Schoultz, Säljö & Wyndhamn, 2001). Findings from these studies have led to a very different view of children s knowledge of the earth from Vosniadou s: young children can and often do understand considerably more about the earth than was previously assumed. They are able to do so because they do not have strong intuitions that influence their concepts and slow their acquisition of knowledge from the culture. Moreover, their knowledge of the earth is fragmented and incoherent (Nobes et al., 2003; Siegal et al., 2004). In this respect the fragmentation account of children s knowledge of the earth is similar to disessa s Knowledge in Pieces (e.g., disessa, 1988; disessa, Gillespie & Esterly, 2004). According to this account, the process of knowledge acquisition in this domain resembles that of doing a jigsaw puzzle. The child gradually accumulates pieces that at first are unconnected and form no picture at all. The pieces are added to and put together until eventually most individuals have a more-or-less complete and coherent picture. There is no theory-like, coherent conception of the earth until this final, cultural view is acquired in our culture this is usually the scientific view. In contrast, the mental model theorists propose that children first have a whole, coherent picture of the flat earth; this picture is then discarded in favour of a synthetic earth; which in turn is replaced by the cultural picture. The two accounts also differ in terms of the origins of concepts. According to the fragmentation view, learning is enculturational from the start: the child s earliest ideas (fragments) about the earth (e.g., that it is spherical) are based on cultural information acquired from, for example, formal and informal instruction and the media. In contrast, young children s initial mental models are supposed to result primarily from strong intuitive 5

6 constraints and observations. In this sense, disessa et al. s (2004) view more closely resembles the mental model account. They suggest that, in domains such as physics, the fragments ( p-prims ) are intuitive elements, typically abstracted from common situations (p. 857) 1. It is very likely that the contrasting accounts of the development of knowledge of the earth, and the discrepant results on which they are based, reflect the two groups of researchers different methods. Critics of the mental model account have argued that children s true knowledge of the earth is not adequately elicited when drawing or modelmaking methods are used. Their criticisms have focused on two types of possible methodological problems: semantic (to do with interpretation of the task) and pragmatic (pertaining to issues of representation through drawing or model-making). Regarding the semantic problems of the earth drawing task, Siegal (1997, 1999) and Siegal and Surian (2004) have discussed the implications of children s conversational inexperience. Especially in the unfamiliar context of the research interview, children s limited conversational understanding often leads to an inability to resolve ambiguity and interpret meanings. Although the instructions of the earth drawing task are apparently very simple ( Draw the earth ; Draw the sky ; Show where people live ), it is possible that some children draw non-scientific pictures not because they lack knowledge of the earth, but because they misinterpret the point of the task and the meaning of the instructions. Indeed, there are numerous ambiguities in the instructions and questions in the mental model theorists interviews that could possibly confuse even conversationally experienced individuals. For 1 However, disessa et al. (2004) also point out that understanding of the earth is dramatically less connected to the kind of rich phenomenology of everyday experiences of force and motion that lie beneath intuitive conceptions in mechanics. The Knowledge in Pieces perspective was developed specifically to deal with experientially rich domains, such as mechanics (p. 888). 6

7 example, the word earth could mean the planet or the ground. Also, it makes sense to say that people live in the world, in houses as well as on earth. As a result of these ambiguities, the mental model theorists might have misinterpreted children s responses and so underestimated their understanding of the earth. The possible pragmatic problems of the earth drawing task include issues of artistic skill. Children tend to be poor artists, and find drawing 3D objects particularly difficult (e.g., Blades & Spencer, 1994; Ingram & Butterworth, 1989). It is possible that even adults would have difficulties drawing a huge sphere like the earth, especially if they were then asked somehow to represent people on the same picture. As a result, children might choose to draw a flat, hollow or dual earth not because they don t know that it is a sphere, but because these are more easily represented on paper. (For discussions of children s drawings and use of symbols, see, for example: Cox, 1992; DeLoache, 2002.) The mental model theorists have also sought to explain the differences between their own findings and those of their critics (Vosniadou et al., 2004). They suggest that the use of only three 3D models (Nobes et al., 2003; Siegal et al., 2004) and one globe (Schoultz et al., 2001) severely limits children s choice. A child who has a dual or hollow earth mental model might not recognize these objects as such and so will not give the appropriate response. In addition, the mental model theorists propose that the discrepant findings occur because the different methods reveal different modes of knowing. They claim that their critics methods elicit only simple repetition or recognition of scientific facts, which is relatively easy and achieved even by young children, whereas their own tasks measure the generative use of scientific concepts (Vosniadou et al., 2004, p.221). Considering the implications of the contrasting accounts for our understanding of conceptual development and for science education, there is an urgent need to explore these issues. The aim of this study was to investigate possible reasons for children appearing to 7

8 have naïve mental models and little knowledge of the earth when they are asked to draw or make models of the earth, but not when other methods are used. Specifically, we sought to examine the proposal that the mental model theorists findings result from semantic and pragmatic problems with their task. To avoid the objection that critics of the mental models account have employed only recognition tasks, we used the same generative drawing task and questions used by Vosniadou and her colleagues. In the present study, for the first time, adults were tested with the earth drawing task that the mental model theorists have used with children. If adults who have a clear scientific understanding of the earth give non-scientific responses to the mental model theorists task, the validity of the task would have to be questioned. Moreover, if they give the same responses as children s so-called initial and synthetic responses (e.g., they draw flat earths and say that people live only on top of the world), it follows that these responses do not necessarily indicate the presence of naïve mental models. At least as far as knowledgeable adults are concerned, the explanation of these non-scientific responses must be methodological (semantic or pragmatic) rather than conceptual. It is possible that adults and children sometimes respond incorrectly to a task for different reasons. For example, young children can be unaware of a task s complexities and so find it easier than adults. Adults might draw non-scientific pictures of the earth for semantic reasons (they find the phrasing of instructions ambiguous), while children draw them for conceptual reasons (e.g., they have naïve mental models). To be sure that adults and children s non-scientific drawings and answers are given for the same reasons, it is important that they give identical responses. Since there are an infinite number of possible drawings (including, for example, star- or banana-shaped earths), it is very unlikely that two identical pictures (showing, for example, the hollow earth) would be drawn for different reasons. Moreover, if the adults gave explanations for their non-scientific 8

9 responses that are likely also to apply to children (e.g., I thought that earth meant ground, or I don t know how to draw a sphere ), then we could be confident that adults and children s responses occur for the same reasons. To illustrate this point, imagine asking adults and children What is the product of 7 and 8?, and finding that, while most adults gave the correct answer (56), many said it was 15. If we found that many children also said that it was 15, we could be reasonably confident that they did so for the same reason as the adults: there are an infinite number of possible answers, and it would be an extraordinary coincidence if they gave this same one for different reasons. Furthermore, if we then interviewed the adults who answered 15 and were told, for example, I thought that product meant sum, we could be virtually certain that this semantic explanation also accounted for the children s response, since, if many adults don t know the meaning of product, nor will many children 2. In this study we therefore investigated not only if adults, like children, sometimes give non-scientific responses to the mental model theorists drawing task, but whether these responses are identical to children s (e.g., they draw flat, dual and hollow earth pictures). Moreover, we examined adults explanations for their own non-scientific responses to assess whether these were likely to apply to children (e.g., the adults found the task ambiguous and challenging). If adults non-scientific responses were identical to children s, and their explanations were applicable to children, then the reasons for adults responses would very probably also account for children s. 2 This conclusion would be further strengthened if, as with the recent studies of children s understanding of the earth, alternative forms of testing (e.g., asking What is 7 multiplied by 8?, or Which of these models looks most like the earth? ) resulted in few or none of the participants giving the incorrect or non-scientific response. 9

10 When considered in the context of the earlier studies of children s understanding of the earth, such findings with adults would provide a compelling and parsimonious explanation of the discrepant findings of proponents of the two accounts: children give so-called naïve responses to the mental model theorists tasks simply because they don t understand the instructions and questions, and find them too difficult. Until now, researchers in this field have only tested children. It appears that all have assumed that the drawing task is so simple that all adults would give scientific responses to all instructions and questions, and that therefore nothing could be learned about children s responses. Yet, as Coley (2000) argues, testing adults with children s tasks has several advantages, not least that To characterize the process of conceptual development, we need to understand the adult model, the modal endstate of development in a given society. (p. 82). Another reason for giving children s tasks to adults is that adults are better able to reflect on, and communicate about, their interpretation of the task, any problems they encounter, and the meaning of their responses. As Light (1986) points out, children may not be able to articulate, or may not even be aware of, the factors which influence their responding (p. 176). As a result, it is often difficult to know why children behave as they do in research tasks, and so researchers can misinterpret their responses, and give incorrect explanations of them. Furthermore, adults typically have longer attention spans than young children, and so it is possible to conduct longer, more demanding interviews. Adults were given the mental model theorists drawing task to investigate whether any gave non-scientific responses, and, especially, if any of these responses were similar to children s intuitive or synthetic responses. They were also asked to give comments on, and interviewed about the task to examine the reasons for any non-scientific drawings or answers. Of particular interest was whether any adults had naïve beliefs about the earth (e.g., that it is 10

11 flat or hollow) that might explain these responses, and if the adults own accounts provided other possible reasons for their drawings and answers. Method Sample. The participants were 350 college and university students from East London. Consistent with the diversity of this population, ages ranged from 17 to 69 years (M = 27.9, SD = 8.9), and two-fifths (41.4%) were white British, one-fifth (20.6%) South Asian, 10.9% white non-british, 10.0% Black Caribbean and 8.3% Black African. Most (68.5%) were psychology undergraduates, and a majority (70.0%) were female. None of the participants had studied physics or astronomy beyond secondary school. A sub-sample of 55 participants who drew non-scientific pictures was invited for interview. Of these 55, 39 were interviewed (70.1% response rate, 11.1% of the sample). Measures. The instructions (1-3) and questions (4-9) in the drawing questionnaire were very similar or identical to those of Vosniadou and Brewer s (1992) and Samarapungavan et al. s (1996) interview schedules: 1) Draw the earth 2) Draw where the sky and clouds go 3) Draw some people to show where people live 4) What is the shape of the earth? 5) Where is the sky? 6) Where do people live? 7) If you walked for many days in a straight line where would you end up? 8) Is there an end / edge of the earth? 9) What is below the earth? 11

12 The multiple-choice answers to the questions (Table 1) were the most frequent responses reported by Vosniadou and her colleagues, with the addition of a request to add any other response ( Other please state ). At the end of the questionnaire, participants were asked to comment on whether they understood the instructions and questions, and the reasons for any problems. The follow up interview was based on the 3D model choice task used by Siegal et al. (2004) and Nobes et al. (2003). This task is adapted from Vosniadou and Brewer (1992) but involves the use of seven 10cm plastic models, instead of drawings. Each represents one of the most common mental models proposed by Vosniadou & Brewer (1992) and Samarapungavan et al. (1996). Participants are asked to choose a model that best represents the earth, and to show the locations of people using Lego figurines, and of the sky using cotton wool to represent clouds. This task was followed by a series of open-ended questions that focused on any nonscientific responses to the drawing questionnaire and 3D model choice task, and on the reasons for any inconsistencies or problems with either task. Procedure. The questionnaires were administered to participants either individually or in small groups. Before distribution, participants were informed that the study was part of a programme investigating children s understanding of science and that, since the instructions and questions were originally designed for children, they might seem simple. It was pointed out to them that there was no deception, that all data were confidential, that participation was voluntary, and that they should answer the questions entirely independently and as accurately as possible. Most questionnaires were completed in five minutes. Participants who drew non-scientific pictures of the earth were invited to attend a follow-up interview within a few days of completing the questionnaire. These one-to-one interviews lasted minutes and took place in quiet interview rooms. The researcher 12

13 reminded the participant that she was interested in their ideas about the earth; that the questions were developed for children and therefore might sound simple; that there were no trick questions; that all data were confidential; and that they could terminate the interview if they wished. Interviews were video-recorded and the interviewer took notes for later transcription. These participants were then given the 3D model choice task. Since the main point of interest was the reason for any non-scientific responses, the second part of the interview consisted of asking participants to clarify and explain these responses and any inconsistencies across tasks (e.g., drawing a flat earth but choosing the spherical 3D model). For example, the interviewer would ask, In your drawing the earth seems to be flat but here it seems to be round. Can you explain? Ambiguous responses were followed up with additional questions such as, Could you say a bit more about this? Interviewees were also encouraged to give feedback on the questions and report which ones they found unclear, and why. Results Drawings of the earth. Eight main categories of drawing were identified according to the shape of the earth (round, semicircular or flat), the locations of people and the sky (on top, all around or inside), and the number of pictures (one, two or three). All drawings were coded by two independent judges. Inter-rater reliability was 94.3%. When their judgments differed, codes were agreed through discussion. Examples of each category are shown in Figure 1. Insert Figure 1 about here Scientific earth. The largest group of participants (165, 47.1%) drew this version of the earth: a circle with the sky and the people all around. Some showed the location of people by drawing landmasses, but in a large majority of these pictures the people were represented by vertically oriented matchstick people distributed within the circumference of the circle: only 13

14 15 (9.1%) of this group drew the people oriented towards the centre of the circle and placed around the circumference of the earth. Circular sky on top pictures were drawn by the second largest group (27, 7.7%). These resembled scientific drawings except that the sky was located only over the Northern Hemisphere. Circular-magnified people. Twenty-two (6.3%) participants drew scientific earths in which the people were magnified and located on the earth with an arrow, line or telescopelike cone. In seven of these pictures, the sky was depicted above the magnified people. Semicircular earth. In ten (2.9%) pictures the sky was located above a curved line or hemisphere. People, and / or houses were placed on this line by six participants, and below it by the remaining four. Flat earth pictures were drawn by twenty-two (6.3%) participants. These showed one or more people, usually with buildings, mountains or trees. In eleven of these drawings people stood on a straight line. One other participant drew an oval shape and another a square, both with people on the top surface and the sky above. All of these pictures were similar or identical to the children s drawings that Vosniadou and her colleagues have interpreted as indicating flat earth mental models. Three pictures. A group of twenty-one (6.0%) respondents drew separate pictures in which, first, the spherical earth was depicted as if from space, without sky or people; second, the clouds, often above trees or houses, were shown from the perspective of the earth s surface; and third, a person or people appeared on a flat plane, usually alongside houses. Fifteen of these participants numbered each picture, indicating that they corresponded to instructions 1, 2 and 3, respectively. Dual earth. Fourteen (4.0%) participants drew both the scientific and flat versions of the earth. These drawings were identical to the dual earth pictures identified by Vosniadou and 14

15 her colleagues. Two other participants drawings closely resembled dual earth drawings, except that the two versions were separated by the word or. Hollow earth. Sixteen (4.6%) participants drew circles with the sky inside the top of the circle, and the people inside the bottom of the circle. These pictures were identical to those produced by children who are said by Vosniadou and her colleagues to have hollow earth mental models. Of the remaining respondents, most drew scientific pictures with either the people or sky omitted or located on one side. Nine (2.6%) did not produce a drawing. Participants comments on the drawings. Of the 261 participants who wrote comments, 174 reported having one or more problems with the questionnaire. In total, 74 (21.1% of the sample) said that these problems concerned the drawings. Eighteen (5.1%) of these were general points about the ambiguity or challenging nature of the task. For example: - I was unable to draw the earth (P64 no drawing) 3 - This is impossible to really draw for adults and children! (P887 circular, no people) - V. difficult to work out how to draw them esp. if didn t read ahead. (P892 - semicircle) Ambiguity - meaning of earth. Sixteen (4.6%) participants commented that they found the word earth ambiguous. For example: - Question 1 confused my sense of what was meant by earth - did you mean soil or did you mean the world? (P60 scientific) - Not explained if earth the planet or earth the ground! Bit confusing! (P104 circular, no people) 3 Participant number and drawing category in parentheses. All quotations are from written comments made on the questionnaires unless stated that they were given during interviews. 15

16 Perspective. Fourteen (4.0%) participants reported that they did not know whether to represent the earth from the global (scientific) or local (flat) perspective. It is likely that they, too, were confused by the meaning of earth. Their remarks included: - From which view? Outside? Inside? (P34 - flat) - Wasn t sure if it meant the earth as a whole or the earth as seen from our viewpoint, just the part where we live (P802 - flat) - When first asked to draw earth drew aerial view but when asked to draw people and sky made me think of earth as mud rather than whole planet (P851 scientific) Scale. A similar problem with the drawing task concerned how to represent the earth and people in the same picture. This point was made by 19 (5.4%) participants, some of whose comments indicated that this difficulty was compounded by that of perspective: - People were obviously too big to fit on the earth picture (P19 - scientific) - Did not know if I should draw the earth or the ground. If you draw the earth, you can t draw the sky, nor the people (P22 two pictures with or ) - Wouldn't be able to draw people as you wouldn't see them this far away (P110 circular, no people) Number of pictures. Three participants remarked in their questionnaires that they did not understand how many pictures they should draw: - Didn t explain whether they wanted all 3 pictures in 1 or 3 separate pictures (P110 circular, no people) - 3 separate pix?! (P487 3 pictures) - The 1st 3 questions were unclear as to whether the drawings were inclusive of instructions 1,2,3, or separate drawings. Ambiguous. (P838 circular, sky on top) This issue was clarified during follow-up interviews of participants who had drawn a dual earth or three pictures: 16

17 - I drew the earth with the continents and the sky all around. I separated the people where they live, which is outside the earth, but I should have drawn them maybe inside the circle (P38 dual earth) - You asked please draw the earth and this was my natural reaction, to draw a circle with the land and the sea (points at circular earth). Then you said draw the sky and clouds and then I just said here is the sky at the top of the earth and that s the bottom where I put the people. (P400 3 pictures) Illustrative section. A recurring theme in the interviews was that pictures represented the earth, sky or people by showing only an illustrative part or example: - This (circle) is the earth. I ve done the clouds here and the people here as a representation of where they would be, like all the way around. (P148 - hollow) - When I drew this I was thinking about only one place on the earth. Wherever you are on the face of the earth there is always the sky above you. (P803 - hollow) - I didn t continue my sky all around the little drawing of the earth not just because I thought the sky only existed at the top of the world but because I just intended to represent it (P991 circular, sky on top). Questions about the earth Frequencies of responses to the multiple choice questions, including answers that were added by the participants, are presented in Table 1. Insert Table 1 about here Question 4: What is the shape of the earth? The conventional scientific answer to this question a sphere was given by the large majority (87.5%) of the respondents. Most of the non-scientific answers were that the earth is Oval like a flattened ball. In the questionnaire there were only two comments made about this question, and both suggested that this answer 17

18 was given for the correct reason that the earth is not a perfect sphere: - Not sure but don t think the earth is perfectly round like a ball. (P46 - scientific) - But slightly flattened at each end (483 no picture) During their follow up interviews, eight participants revealed some confusion about, or difficulty in explaining, how the earth could be round and yet seem flat. For example: - Well it s round but it s flat as well I can t explain it s flat round I think from a scientific view it s round but practically speaking it is flat. (P814 - flat) Question 5: Where is the sky? Although the large majority (85.4%) responded that the sky is all around the earth, another 8.5% said that it is inside the earth. Thirteen participants commented on the questionnaire that this question caused them problems, and their remarks revealed that the likely reason for this response is the ambiguity of the term sky. These participants observed that, since the atmosphere is part of the earth, it makes sense to consider the sky being within the earth: - Did you mean if it was in space or in the atmosphere? (P79 circular, no sky) - Sky meaning what we see - blue above + clouds - or sky everywhere - eg. outer space surrounding earth? (P893 - scientific) There were also 18 participants who said that the sky is only on top of the earth. Several comments indicated that these answers arose from the ambiguity concerning the sky s location, since it is both above and all around the earth. - All around the earth and on top of the earth seems like the same thing (P136 - scientific) - Can also be perceived as above or on top of the earth (P895 circular, sky on top) One participant wrote that she was unsure about the location of the sky: - I have never really thought about where the sky and clouds are in relation to the whole world the sky and clouds are always above. (P837 scientific) 18

19 Nine follow up interviews showed that others shared this problem: - I m thinking where the sky is. Everybody is seeing it, right? Is it like it s all around? I don t think I know I just assumed that it s up there (P67 circular, sky on top) - I don t know actually, I would have thought the sky s on top (P807 - hollow) - [Where would the sky and the clouds be with regards to this sphere?] I presume over England here. I suppose they are hovering over various I don t know. (P814 - flat) Question 6: Where do people live? Only a half of the participants gave the expected scientific response - All around the earth. Thirteen participants indicated that none of the answers was correct, adding their own responses such as On the surface, On the land, or In houses. A total of 45 (12.9%) participants commented that they had problems with this question. These explained why a quarter of the sample said that people live Only on top of the earth : - People do live around the earth but also only on top ie not inside. (P21 circular, sky on top) - This question is quite ambiguous. On top could mean surface therefore one option could be on top of the earth and all around? (P52 - scientific) - People do live on top of the earth in one sense! (P895 circular, sky on top) Follow up interviews shed light on the response given by a sixth of the participants, that people live inside the earth. They revealed the ambiguity of terms such as around, on top and inside, and pointed out that we don t live outside the earth (i.e., in space), but instead live in countries and in the atmosphere, which are parts of the earth. For example: - People also live inside the earth, because there is no life, there is no light or air outside so it would be impossible for people to live outside the earth (P33 circular, sky on top) - If we re not inside, how come we re not floating around in space? We re inside these countries, these islands (points to continents). [And what s outside?] Galaxy and things like that (P809 - hollow) 19

20 Question 7: If you walked for many days in a straight line, where would you end up? Almost two-thirds of the sample gave the expected response of Back where I started, and 46 (13.1%) commented that they had problems with this question. Eight participants ticked that they would end up At the end / edge of the earth (see Question 8). Seventy-one answered that they would end up Somewhere else, such as another town or country, or the sea. Twenty-three comments suggested that such responses result from the reasonable point that a long journey could end up anywhere, from the ambiguity of for many days, or from the problem of walking into obstacles: - Needs to be specific on the length of time walking (P17 circular, sky on side) - If I walked outside my front door I would end up in another person s house just across the road. (P35 flat) - You go round and round, you could end up anywhere (P37 dual) - Didn't know if I could go across water (P872 scientific) Seventeen participants answered with In space or the sky. This response was explained by sixteen comments that indicated that the term straight line was unclear: - Vague. If direction was up = in space or sky. If direction was forward, back where I started (P148 - hollow) Question 8: Is there an end / edge of the earth? A large majority (84.0%) of respondents answered No, there is no end / edge of the earth. Of the 16 comments about this question, most indicated confusion over the words end and edge, observing that these terms can refer to, for example, the coast or the edge of space or atmosphere: - How do you define end/edge? Do you mean the continents, or the planet? (P6 circular, no sky) - Is the end the poles? (P99 - scientific) - There is an outer area which I guess you could call an edge. Where do you stop? The 20

21 universe, the solar system? (P813 circular, sky inside) - One day it might end. Ambiguous (P886 circular, no sky, no people) Question 9: What is below the earth? Fewer than three-fifths of the participants gave the expected scientific answer Sky or space to this question. The majority of the forty-four (12.6%) who commented on this question referred to the ambiguity of the term earth : if it refers to the globe, the answer should be space; if, however, it refers to the land, the answer is ground, lava or possibly water: - Did you mean below the earth in the solar system or below in middle earth? (i.e. inside the earth?) (P16 - scientific) - Confusing - I interpreted it to mean what is under the surface of the Earth, rather than around and below the Earth (P425 - scientific) General comments. There were 50 (14.3%) participants who commented that all the questions were ambiguous, confusing or challenging. For example: - Good god, I had to think about these answers, quite thought provoking. (P73 - flat) - To be honest I can t understand the meaning of all these questions (P808 3 pictures) - Didn t understand most of them (P820 - flat) - These questions are not easy for adults to answer. For young people this would be difficult confusing & probably quite upsetting for many! (P887 circle, no people) Discussion Fewer than half of the adult participants in this study drew the conventional scientific version of the earth. There was a variety of alternative drawings, including all of the main types of pictures drawn by children: similar proportions of adults drew flat, dual and hollow earth pictures as did the children in the mental model theorists studies. Moreover, up to half gave non-scientific responses to each of the apparently simple questions. These same non- 21

22 scientific drawings and answers have been interpreted by previous researchers as indicating that children have naïve mental models and intuitive constraints. The adults non-scientific responses were not given because the participants had naïve mental models or intuitive constraints: the follow-up interviews confirmed that none believed the earth to be flat, dual or hollow. At least as far as adults are concerned, these responses are neither naïve nor intuitive. Many adults reported finding the drawing task designed by the mental model theorists for children as young as five years - both confusing and challenging. They encountered a range of problems that explained their non-scientific responses. These problems were principally semantic: participants found the apparently simple instructions and questions ambiguous and unclear. For example, different interpretations of the term earth led to very different pictures and answers. Participants who assumed that it refers to the ground or soil were correct to say that people live on top of the earth, and that there are rocks or lava below. In addition, since we do not live outside the earth, and we say that people live in the world, it can make sense to say that people live inside the earth. Similar problems were apparent with the meaning of terms such as sky, edge, straight line and end up. When a participant of any age gives one of these answers, it does not mean that they do so because they have intuitive constraints of flatness and support, and have initial or synthetic earth mental models. The drawing instructions also caused difficulties because they provide no information on the perspective from which the earth should be depicted, or on how many pictures should be drawn. The first instruction, to draw the earth, indicates that the global perspective is expected. But the second, to draw the sky, and particularly the third, to show where people live, strongly suggest that a local perspective is required. For reasons of scale, no realistic picture could show both the earth and the people. Many participants therefore assumed that 22

23 they should take the local perspective. Others chose to show both perspectives combined in one picture, or separately in two or three pictures. The drawing task also poses pragmatic problems: how to draw the earth, sky and people. For example, depicting a 3-dimensional shape - especially the huge, spherical earth - in the 2-dimensional medium of a picture, is difficult even for accomplished artists. In addition, since the sky surrounds the earth, there is the problem of occlusion: if the sky is to be drawn from above, it is not possible to see the people below. A small but substantive proportion of adults had conceptual problems with the task, in particular concerning the location of the sky. This finding might suggest support for the mental model account in that some intuitions are so strong that they persist for some individuals even into adulthood. However, rather than saying that, for example, the sky and people are only on top of the earth, these participants reported that they did not know: they had neither scientific conceptions, nor non-scientific misconceptions. Like the children in previous studies (e.g., Nobes et al., 2003, 2005; Siegal et al., 2004), adults who lacked scientific knowledge were theory-free. The finding that many adults produced exactly the same non-scientific drawings and answers as children strongly suggests that adults and children s responses occur for the same reasons. Moreover, most of the explanations provided by the adults are likely to apply to children. If, for example, adults have difficulties showing both the earth and the people on the same drawing, so too will children. There is no reason why children should find the task less ambiguous, or be more skilful artists than adults. On the contrary, children probably find the semantic and pragmatic problems of the task even more challenging than adults. We interpret the pictures drawn by adults reported here, and by children in previous studies, as attempts to solve these problems. Several methods are used by the participants. First, they employ symbols that are culturally accepted and widely used in diagrams such as 23

24 maps, technical instructions, notices and weather forecasts. For example, matchstick people, clouds and a circle are used to represent people, the sky and the 3-dimensional earth, respectively. Second, the participants follow drawing conventions. An almost universal convention is that people are drawn vertically, in contrast to their actual orientation around the world. Another common convention is to locate the sky vertically above, rather than around, the earth. Third, earth drawings are illustrative: they depict examples or parts rather than the whole. For example, even the scientific pictures show only a small number of people and clouds. Similarly, many drawings depict an example of the places in which people live, or of where the sky is. Each type of picture drawn by adults in the present study, and by children in previous studies, can be explained in these terms. First, the scientific earth drawings use convention and symbolism to solve the problems of perspective, scale, dimension and occlusion. The earth is drawn in two dimensions, and no attempt is made to make it look like a sphere rather than a circle; cloud-shapes or shading represent the sky; and vertical matchstick people are placed in or around the circle to represent people. In this way it is possible to represent the earth from the global perspective, and to show the sky and people in the same drawing. Similarly, these drawings are illustrative: a small number of people and clouds are shown as examples of where they are located. It is only through the use of such methods that the scientific view of the earth can be represented on paper: even a photograph could not solve problems such as perspective, scale and occlusion. The scientific version of the earth that older children and adults were expected to draw is actually a highly symbolic conventional representation. It follows that participants of any age who are unaware of, or unskilled in the use of these conventions cannot draw the scientific version of the earth. The circular-sky on top drawings use the same symbols as the scientific pictures, but also follow a common convention of showing the sky above the vertically-oriented people. 24

25 This representation solves the problem of occlusion by showing only an illustrative section of the sky. But for some participants there is also a conceptual reason for drawing the sky above the earth: they do not know its location relative to the whole earth. Flat earth drawings show a small illustrative section of the earth taken from a local perspective. Participants who draw these pictures interpret the earth to mean ground, and the first instruction to draw the earth to mean as seen from its surface. This approach therefore results from the ambiguities of the task, and neatly avoids the issues of perspective, scale, dimension and occlusion. It does not indicate a belief that the world is flat. Dual earth pictures are interpreted by the mental model theorists as showing that the artist believes that there are two earths. The present findings demonstrate that this interpretation is incorrect: they are actually two separate pictures of the same object seen from different viewpoints: one is a circle depicting the earth from the global perspective; the other is a flat earth picture showing it from the local perspective. Some participants even separated the two pictures with the word or. They are drawn because the problems of terminology, scale and number of pictures lead participants to depict the earth from both perspectives. Hollow earth pictures are similar to three-picture and dual earth drawings in that they solve the problem of perspective by showing both the local and global views. However, like the magnified and semicircular drawings, they do so in a single picture. They depict both the whole, spherical earth and an illustrative section in which people live on a flat surface with the sky above. There was no support for the mental model theorists claim that these pictures reflect a belief that the earth is a hollow sphere containing people and the sky. In the mental model theorists studies (e.g., Diakidoy et al., 1997; Samarapungavan et al., 1996; Vosniadou & Brewer, 1992), children are provided with little or no information about, in particular, which perspective is to be taken, and how many pictures are to be drawn, or models to be made. There is therefore considerable scope for the participants to 25

26 misinterpret the instructions and questions, and for the researchers to misinterpret the responses. In contrast, when the same task is given with reference to a set of 3D models (e.g., Nobes et al., 2003; Panagiotaki et al., 2005; Siegal et al., 2004) or pictures (Nobes et al., 2005; Straatemeier et al., 2005), or a globe (Schoultz et al., 2001), it is clear that a single, global perspective is to be taken: the stimuli enable the child to make sense of the questions. The word earth and questions such as Where is the sky?, Where do people live? and Is there an end or edge to the earth? are therefore considerably easier to interpret. Similarly, when participants are given Lego people or cotton wool clouds, problems such as scale and occlusion do not have to be solved. The objects contextualize and disambiguate the instructions and questions, and so give children access to shared meaning with the researcher. These findings support Siegal and Surian s (2004) argument for a shift in emphasis in cognitive developmental research towards recognition of the influence of conversational processes. Drawing flat, hollow and dual earths, and saying that people live on top of the earth, does not indicate conceptual immaturity. Instead such responses result from miscommunication and misunderstanding in the conversation between researcher and respondent. As Siegal (1999) points out, even adults can lack the conversational awareness required to demonstrate their true conceptual competence. We have shown that the drawing task is a poor measure of conceptual development because its profound ambiguities lead even adults to misinterpret the instructions and questions. An important claim of the mental model theorists is that children s non-scientific responses are consistent and theory-like. The reasons for non-scientific responses suggested here also account for this reported coherence: participants will tend to interpret (or misinterpret) the instructions and questions consistently throughout the task. For example, respondents who assume that the first instructions refer to the ground rather than to the globe - and that they are therefore supposed to take a local perspective - will draw a flat earth picture. 26