Some individuals have even survived an entire year without eating.

 This sea slug runs on sunlight. Yes, it literally photosynthesizes.

The eastern emerald elysia (Elysia chlorotica) blurs the line between plant and animal.

This bright green sea slug can perform photosynthesis — the process plants use to convert sunlight into energy — by stealing chloroplasts from the algae (Vaucheria litorea) it eats.

Once absorbed, these chloroplasts are stored in the slug’s cells, enabling it to live off sunlight alone for months at a time. Some individuals have even survived an entire year without eating, sustained purely by solar energy.

This solar-powered sea slug lives in sunlit habitats like tidal pools and salt marshes along the U.S. East Coast. Its green color, derived from its chloroplasts, serves as a natural camouflage, helping it evade predators. Growing up to 60 mm long, Elysia chlorotica is a vivid example of evolutionary innovation — and a living demonstration of how energy efficiency might work in unexpected ways.

Its unique ability to photosynthesize opens new doors for research into sustainable energy and the crossover potential between plant and animal biology.

Binod Kumar Simkhada