The planet might once have been dominated by microbes that used a molecule other than chlorophyll to harness Sunâ€™s rays.
Billions of years ago, a slowdown in Earth's rotation period lengthened days and offered photosynthesizing bacteria the chance to release more oxygen, transforming the planet.
Two species of sacoglossan sea slugs have been found to be able to sever their heads from their bodies and regrow a replacement by researchers in Japan.
If humans had green skin, for instance, what if it granted us the ability to perform photosynthesis, which plants use to live off of sunlight?
By grafting their roots together in a hidden underground network, trees could be forming giant "superorganisms" that span entire forests.
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