Some 7,500 years ago, humans discovered that cows didn’t need to hoard all of their milk for just their calves, and they decided they should horn in on the action as well. And while it might be a little strange to imagine taking another animal’s milk and drinking it yourself (especially when humans had to genetically evolve to do so), it is hard to deny cheese and yogurt

But, the primary component of milk, the protein casein, isn’t just a tasty source of sustenance-you can also use it to replace petroleum-based synthetic plastics for a more sustainable alternative.