Ancestors of Darwin's finches were _______eating.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the dietary habits of the ancestors of Darwin's finches. We need to identify what these ancestors primarily consumed.

2. **Identifying Darwin's Finches**: Darwin's finches are a group of small birds that are known for their diverse beak shapes and sizes, which are adaptations to their feeding habits.

3. **Researching the Diet of Ancestors**: The ancestors of Darwin's finches were primarily seed eaters. This means that their diet mainly consisted of seeds, which influenced their physical adaptations over time.

...