One reason we need to preserve biodiversity: over billions of years, life has accumulated amazing knowledge, which we are scarcely beginning to tap.
For example, 'glass sponges' are sponges living in the mud at the ocean floor which have beautifully optimized skeletons made of glass: that is, silica. This one is called Venus’ Flower Basket. As we zoom in, we see more and more structure. Its lattice of silica has diagonal bracings for extra strength.
But the true beauty of it only becomes clear under a microscope!
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