👁️ Our eyes have 3 types of color-sensitive receptors or cones: 🔵🟢🔴 🐦 But birds have 4 color cones! 💭 Can you imagine how vibrant the world looks to a #bird? 📖@VirginiaMorell & @NatGeo on a @PNASNews study by M. Stoddard api.nationalgeographic.com/d…