Scientists wanted to find out how the numbers of lizards on the Mercury Islands changed after they had killed all the rats.
They trapped lizards so they could count them. The graph shows their data.
| a) |
How many lizards were caught per 100 traps in 1989? __________
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| b) |
All rats were taken off the Mercury Islands in 1986.
How does this appear to have affected the number of lizards on the islands?
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| c) |
How do you think the rats affected the lizard numbers on the islands before 1986?
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