The sea slug, Elysia chlorotica, can transform into plant like and survive just on photosynthesis. The undertaking is highly unusual for an animal but the mollusk somehow manages to steal millions of green-colored plastids, which are like tiny solar panels, from the non-toxic brown alga, store them in their gut lining, and become photosynthetic, or…
https://sparkonit.com/2018/05/06/sea-slug-turns-plant-like-survives-solely-on-photosynthesis/
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