Communities: Students should be able to, when provided with appropriate information:

The idea

This statement is a stem that introduces the practical skills assessed in the Communities topic. It tells you that exam questions will supply data, such as a table of population counts, a graph of predator and prey numbers, or a written description of a habitat, and you must work with that information rather than recall facts alone. The phrase 'when provided with appropriate information' means the answer is extractable from the resource: you read values, spot trends, compare sets of numbers and apply ecological ideas such as interdependence, competition and cycling of resources. For example, given counts of two plant species across a shaded-to-sunlit transect, you might describe how one declines as light increases. Always quote figures with units and link each point to the ecology you have learned.

What earns the marks

• Read the supplied resource carefully and identify the ecological quantities it contains, such as population size, percentage cover, light intensity or temperature.
• Quote numerical values with correct units when describing a pattern, for example 'the population rose from 40 to 120 between day 2 and day 6'.
• Describe trends using comparative language such as increase, decrease, plateau or fluctuate, rather than listing numbers without comment.
• Link each observation back to an ecological process, for example competition for light, predation, or interdependence between species.
• Where the resource shows more than one variable, compare the variables directly instead of describing each one in isolation.
• Use the command word in the question to decide the depth needed: describe requires the pattern, explain requires a mechanism or reason.

Common mistakes and how to put them right

• Copying numbers from the resource without saying what they show.

  Put it right: Add a comparative statement, such as 'species A increased while species B decreased'.

• Ignoring units or misreading the scale on a graph axis.

  Put it right: Check the axis label and scale before quoting any value, and carry the unit through.

• Writing generic ecology recall that is not supported by the resource.

  Put it right: Anchor every point to a specific figure or feature in the supplied information.

Exam tips

• Underline the command word and the resource reference in the question before you start writing.
• Plan two or three linked points, each pairing a figure with an ecological explanation, rather than writing one long unstructured paragraph.
• If the resource is a graph, quote values at two clearly separated points to show the direction and size of the change.
• Check that every claim you make can be traced to something visible in the supplied information.