<p>Student activity AB1.17.1 Book links: Page 52 Lesson reference: B1.17 Changes in distribution Specification links: B1.4.2 a–d</p><p>Changes in distribution</p><p>Getting started The maps below show the distribution of bumblebees in the UK before 1960 and after 1960. They show the changing distribution of the southern local species of bumblebee over a period of time when there were changes in both the extent and practices of farming, including the use of chemical pesticides and machinery. </p><p>Investigating Look carefully at the maps and the accompanying key before answering the questions.</p><p>Practical activities have been checked for health and safety advice by CLEAPSS. All users will need to review the risk assessment information and may need to adapt it to local circumstances. 127 © Oxford University Press 2011 This document may have been altered from the original. Thinking about A Describe how the distribution of southern local species has changed over time. B Which of the two farming practices mentioned above are most likely to have led to this change in distribution? Suggest a reason why. C A second species (mainland species) has also changed in distribution. What changes can you observe from the maps? D The mainland species is relatively unaffected by the farming techniques. Explain why you think the mainland species has changed its distribution. E Most scientists think that bumblebee numbers have decreased overall. What effect will this change in numbers have on other organisms, such as flowering plants? F Explain why humans should be concerned about the change in bumblebee numbers. G How might increasing organic farming methods affect insect numbers? H What conservation methods could be used to change the decline in numbers of bumblebees?</p><p>Practical activities have been checked for health and safety advice by CLEAPSS. All users will need to review the risk assessment information and may need to adapt it to local circumstances. 128 © Oxford University Press 2011 This document may have been altered from the original.</p>