In an effort to decrease the environmental cost of single-use plastics, scientists, engineers, and designers are increasingly turning to nature to look for sustainable alternatives. Such ecologically friendly alternatives include liquid wood, algae insulation, and polymer substitutes made from fermented plant starch like in corn or potatoes. These green substitutes to plastic do more than stem the growing tide of plastics: they also address issues such as safely housing a growing population, offsetting carbon emissions, and returning nutrients to the earth.