Do you see black or gray specks, strings or cobwebs that drift about when you move your eyes? It could be eye floaters. These are more common with age and can cause retinal tears — a sight-threatening condition. Hear from Dr. Amir Khan, an ophthalmologist, in this Mayo Clinic Minute. https://mayocl.in/2suaxrZ | Mayo Clinic

2.7M views · 24K reactions | The evolution of the human eye - We created this video showing the evolutionary stages of the eye, from basic photoreceptors to the modern eye. | The Brain Maze | Facebook