Dew claws in dogs are similar to the short toes that cannot reach the ground in pigs cattle and deer. they do not have any function. what do they tell us about the ancestry of these organisms

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?