Suchergebnisse

Although chimpanzees generally grasp small objects imprecisely between the knuckle joint of the index finger and thumb, they are capable of a true precision grip, which resembles the human pincer grip. They also grip small objects between the index and middle finger. The development of these precision grips takes place over several years into adulthood and they are not frequent before 8 years of age. Precision grips and imprecise grips are equally likely to be selected for objects of small size. Thus, not only is precise prehension relatively delayed in chimpanzees but also there is lack of consistency in selecting the distal parts of the index finger for thumb opposition. This is a qualitatively different developmental pattern than occurs in human infants who systematically select precision grips for small objects by 15 months.

Abstract In this investigation, we examined children's knowledge of cosmology in relation to the shape of the earth and the day‐night cycle. Using explicit questioning involving a choice of alternative answers and 3D models, we carried out a comparison of children aged 4–9 years living in Australia and England. Though Australia and England have a close cultural affinity, there are differences in children's early exposure to cosmological concepts. Australian children who have early instruction in this domain were nearly always significantly in advance of their English counterparts. In general, they most often produced responses compatible with a conception of a round earth on which people can live all over without falling off. We consider coherence and fragmentation in children's knowledge in terms of the timing of culturally transmitted information, and in relation to questioning methods used in previous research that may have underestimated children's competence.

AbstractChildren's understanding of properties of the earth was investigated by interviewing Asian and white British classmates aged 4−8 years (N = 167). Two issues were explored: whether they held mental models of the earth (Vosniadou & Brewer, 1992) or instead had fragmented knowledge (di Sessa, 1988); and the influence of the children's different cultural backgrounds. Children selected from a set of plastic models and answered forced‐choice questions. Using this methodology, there were no significant differences in the overall performance of Asian and white children after language skills were partialled out. Even young children showed an emerging knowledge of some properties of the earth, but the distributions of their combinations of responses provided no evidence that they had mental models. Instead, these distributions closely resembled those that would be expected if children's knowledge in this domain were fragmented. Possible reasons for the differences between these findings and those of previous research are discussed.