Answer: The chipmunks in the first scenario will start climbing the tree in search for food when it will be finished on the ground.
In the second scenario the process will be natural selection.
Step-by-step explanation:
In case, when the chipmunks will not find food on the ground then they will start climbing trees, this will help them to get food from there as well.
This adaptation will develop over a period of time and will take place in group.
The population of chipmunks who will start climbing tree will survive and reproduce and the population of chipmunks that would not climb will die.The This process is natural selection.