For decades, scientists have been looking for some way to circumvent nature and regrow retinal neuron cells in mammals. Previous studies have shown that many animals have the remarkable ability to regrow retinal cells, but none more so than the zebrafish. One of these was a 2019 study that looked into the “Hippo pathway,” which keeps retinal regeneration dormant. And a 2022 study published in Oxford Open Neuroscience found that when amphibians’ retinal cells are damaged, these animals have “ciliary marginal zone cells” that go to work proliferating new retinal cells. “In many animal tissues that contain stem cells … degenerated cells are replenished by new cells, allowing these tissues to maintain their functions despite continuous cell loss,” the authors wrote.