- Fossils and advanced genetic methods to study relationships between species now tell an intriguing story about a group of tropical centipedes.
- Continental drift (the moving apart of continents) almost 100 million years ago created many species of Ethmostigmus centipedes in the world’s tropics.
- In the Indian peninsula, these centipedes first originated in the southern and central Western Ghats, and then spread across the ranges here.
- India is home to six, fairly large Ethmostigmus centipedes: four dwell in the Western Ghats, one in the Eastern Ghats and one in north-east India.
- Africa, south-east Asia and Australia are also home to other species of Ethmostigmus centipedes.
- The results suggest that a single ancestor gave rise to all Ethmostigmus centipedes in the ancient supercontinent of Gondwana (continents including Australia, Africa and peninsular India comprised this single landmass then).
- The subsequent breakup of Gondwana and the drifting away of different landmasses shaped the early evolutionary history of Ethmostigmus.
- And the Ethmostigmus in peninsular India are very unique.
- They started evolving at a time when peninsular India was moving towards south Asia
- This started around 72 million years ago, in the southern and central Western Ghats.
- Following this, the Ethmostigmus here dispersed to the Eastern Ghats (now home to E. tristis).
- From there, Ethmostigmus dispersed to the southern Western Ghats.
- Ethmostigmus centipedes also reached the northern Ghats from the south-central Ghats too, and later dispersed back to the central Ghats again from there.
