'Darwin's finches' refers to

Options

A. Fossils of birds collected by Darwin at Galapagos islands
B. A type of birds present on Galapagos islands
C. Migratory birds collected by Darwin at Galapagos islands
D. Fossils of reptiles collected by Darwin at Galapagos islands

Explanation

**Step-by-Step Solution:**

1. **Understanding the Term "Darwin's Finches":**
- Darwin's finches refer to a group of small birds that are primarily found on the Galapagos Islands. These birds are significant in the study of evolution and natural selection.

2. **Historical Context:**
- Charles Darwin, the renowned naturalist, studied these finches during his visit to the Galapagos Islands in the 1830s. His observations of these birds contributed to his formulation of the theory of evolution.

3. **Adaptive Radiation:**
- The concept of adaptive radiation is crucial in understanding Darwin's finches. It describes how a single ancestral species can diversify into multiple species, each adapted to different environments or niches.

4. **Diversity of Species:**
- From a single ancestral species that migrated from mainland South America, Darwin observed that 14 different species of finches had evolved on the Galapagos Islands. Each species has unique adaptations, particularly in their beak shapes and sizes, which are suited to their specific feeding habits.

5. **Survival and Natural Selection:**
- The variations in beak shapes among the finches are a result of natural selection, where certain traits become more common in a population because they provide advantages for survival and reproduction in specific environments.

6. **Conclusion:**
- Therefore, "Darwin's finches" refer to the diverse group of finch species found in the Galapagos Islands, which exemplify the principles of adaptive radiation and natural selection.

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