Why does comparative embryology show similarities between organisms that do not appear to be similar as adults?

Explanation

### Step-by-Step Solution:

1. **Understanding Comparative Embryology**: Comparative embryology is the study of the similarities and differences in the embryos of different species. It helps scientists understand how various organisms develop from a single fertilized egg into complex structures.

2. **Common Ancestry**: Many organisms that appear very different as adults share a common ancestor. During the early stages of embryonic development, these organisms exhibit similar structures and features, reflecting their shared ancestry.

3. **Developmental Processes**: The basic developmental processes and genetic mechanisms that guide embryonic development are often conserved across different species. This means that even if the adult forms are quite different, the early embryonic stages can show remarkable similarities.

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