Velcro, a great example of learning from nature. You have a burdock that hooks itself to the fur of other animals passing by. And George de Mestral in the fifties walking his dog was inspired by this and was able to develop Velcro. Now, it mimics the form and definitely gets the function of attaching but it's still made out of petroleum by-products, it still ends up in the garbage when you're done and so when you take biomimicry into the deeper and deeper levels.