As part of an environmental impact assessment, data are collected on the abundance of frogs throughout a 50 km² area by a group of consultants who use the data to work out the area's average density of frogs. By chance, a group of academics from the local university are out collecting the exact same type of data on the same day and in the same 50 km² area. Both groups use the same methods for counting frogs and sample throughout the area randomly. A comparison between the two sets of data shows they attained different estimates of average densities of frogs.

1. Explain what is the likely cause of the differences in the estimates of average densities of frogs between the two sets of data (3 marks)
2. A statistical test is done to compare the two estimates of means and it returns a significant result - i.e. the null hypothesis is rejected. Would this information change your response to (i), above? Why or why not? (3 marks)