The Evolution of Limbs: How Ancient Genes for Reproduction Were Recycled to Form Fingers
UPSC Relevance
Prelims: General Science (Biology - Evolution, Genetics, Hox Genes).
Mains:
General Studies Paper 3 (S&T): Awareness in the fields of Bio-technology. This discovery is a classic example of fundamental research in evolutionary developmental biology (Evo-Devo), which has long-term implications.
Key Highlights from the News
The transition from fins to limbs in aquatic animals to walk on land is a significant event in evolutionary history.
A new scientific study finds that the genetic mechanism that helps form fingers in limbs was originally used to construct parts of the cloacal tissues (reproductive and excretory organs) in fish. ๐งฌ
This means that evolution "recycled" (recycling existing components to serve new purposes) an existing genetic component for a new purpose. This phenomenon is called Exaptation.
This discovery was made through a study on DNA segments that control a group of genes called Hox genes in zebrafish.
This study answers scientists' long-standing questions about how these genes, found in both fish and humans, form different organs.
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