A Plant-Animal Hybrid?

Here's a Wikipedia entry about the emerald green sea slug, a mollusc living in marshes, pools, and shallow creeks, which feeds on algae and incorporates their chloroplasts into its own body. It thereby not only turns green but gains the ability to nourish itself with sunlight:

Elysia Chlorotica

The slug can "capture energy directly from light, as most plants do, through the process of photosynthesis." Once it has established a stable population of chloroplasts, this creature has "been known to be able to use photosynthesis for up to a year after only a few feedings." Some research suggests that a slug may "possess photosynthesis-supporting genes within its own nuclear genome."

An article discussing its biology in less technical language:

The Green Sea Slug Steals Photosynthesizing Power from Algae

The caption on that page declares the emerald green sea slug a true "plant-animal hybrid."

Could a human being -- maybe a superhero mutant -- live on light by photosynthesis, like a tree? I've read this wouldn't be physiologically feasible because that lifestyle requires a mainly stationary existence of standing around exposing a large amount of surface area to the sun for many hours per day. Elysia Chlorotica, however, seems to live like an animal and yet derive nourishment from the sun. Suppose a larger creature with intelligence comparable to ours could do that? Wouldn't that make a cool alien species?

Margaret L. Carter

Please explore love among the monsters at Carter's Crypt.