Mention any one striking similarity that is found in the embryos of all vertebrates at an early stage. What is it indicative of?

Explanation

**Step-by-Step Solution:**

1. **Identify the Striking Similarity**:
One striking similarity found in the embryos of all vertebrates at an early stage is the presence of a notochord. This is a rod-shaped structure that provides support during the embryonic development.

2. **Additional Similarity**:
Alongside the notochord, all vertebrate embryos also exhibit gill clefts. These structures are indicative of the respiratory system in the early stages of development.

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