Biology Fieldwork



Sweep netting in a stream

3. Discussion

Analysing raw data

In the classroom the pupils cut open the leaves (being careful not to cut into the mine). The top layer of the mine can then be lifted off, and the inside of the mine examined. On determining what happened to each of the mined leaves and giving it a corresponding letter (using the key) the results can be recorded in the table on the Observation Sheet. Class results can be collated if desired.

Pupils can use the data they have collected to draw a pyramid of numbers for the holly food chain. The Data Analysis Worskheet provides futher questions.

Evaluation of the method

The Evaluation Worksheet will help pupils to evaluate the methods they used when collecting the first-hand data and to consider the validity and reliability of the data. If time is spent discussing the chosen sampling technique to be used prior to the fieldwork, evaluating the method used should be easy, and there is the option to explore different techniques that pupils feel would increase the reliability of the results.

Other areas for consideration

The method needs to be carefully considered by the pupils.

  • What are the limitations of the method?
  • Are there anomalies that can be explained using the site observational data?
  • How would the results be different if the sampling of holly leaves was carried out at a different time of the year? (i.e. the effect of life cycles)
  • If the tree had been sampled in previous years how might this affect the results?