Aims:

To encourage candidates to:

• acquire an understanding of scientific ideas, how they develop, the factors which may affect their development and their power and limitations

(page 10)

[Pupils] see how scientists work together to develop new ideas, how new theories may, at first, give rise to controversy and how social and cultural contexts may effect the extent to which theories are accepted

(page 19)

Candidates explain how scientific theories can be changed by new evidence and identify some areas of uncertainty in science

(page 18)

Sc1.1 Ideas and Evidence in Science

Candidates should be taught:

1. how scientific ideas are presented, evaluated and disseminated;
   
2. how scientific controversies can arise from different ways of interpreting empirical evidence; [The contribution of Darwin to the development of ideas on evolution is given as a specific example of this on page 22].
   
3. ways in which scientific work may be affected by the contexts in which it takes place, and how these contexts may affect whether or not ideas are accepted;
   
4. to consider the power and limitations of science in addressing industrial, social and environmental questions, including the kinds of questions science can and cannot answer, uncertainties in scientific knowledge, and the ethical issues involved.

Candidates should be able to apply the following ideas arising from the specification content to both historically significant discoveries and to present -day scientific and technological developments, and including any aspects of controversies which arise from them:

• Scientists present their findings in specialist journals, following peer review, to determine whether or not their findings can withstand detailed scrutiny.
  
• The public normally relies on mass media to inform them of issues related to scientific development. The publication of scientists. findings may be simplistic and/or biased, but it can influence the issues which are debated, the public perception of these issues, and the decisions which are made about the funding of it.
  
• Scientists need to think creatively and imaginatively to consider whether or not there are other possible interpretations of their findings and that they may be reluctant to accept alternative explanations if there is a conflict with long-held views.
  
• Scientists own moral, social, religious and scientific views may be significantly influenced by the views currently held by the society in which they live.
  
• New explanations are more likely to be accepted if they can be used to make further predictions, which again can be tested and found to be correct.
  
• Scientists may sometimes not be certain that a specific factor affects an outcome, and this uncertainty increases when there is a limited quantity of data, the situations involved are complex and it is difficult to explain the causes of the outcome.

(Page 21-22)

Block 2.10 Inheritance and Evolution

21. explain the meaning of Darwin's four observations that lead to his theory of evolution:

• all organisms potentially over reproduce
  
• population numbers tend to remain fairly constant over long periods of time
  
• organisms demonstrate variation
  
• some of the variations are inherited.

22. describe how the process of natural selection may result in:

• changes within a species, as illustrated by the peppered moth
  
• many changes over a period of time which may lead to a new species
  
• failure of a species to change which may lead to extinction.

23. explain briefly how organisms may have become fossilised and recognize that fossils provide evidence for evolution.