Eyevolution: Looking Beyond Short-Sightedness

Abstract

To better understand myopia, squid eyes deserve a closer look.This video was produced for the Jove "Film Your Research Contest". It covers the research that Philip Turnbull is undertaking in the Myopia Laboratory at The University of Auckland developing a squid model of myopia. Directed By: Philip Turnbull, PhD (https://twitter.com/fillupt) Video Production: Emma Goodman (http://www.emjgoodman.com/) Audio Production: Matthew Hainey (https://soundcloud.com/hainesmusic) Script writer: Lucy Goodman, PhD (https://twitter.com/neuralucy) Affililations: Auckland Myopia Lab (https://goo.gl/s9SKCW), The University of Auckland (https://www.auckland.ac.nz/) Myopia, or short-sightedness, is reaching epidemic levels worldwide due to our increasingly modern lifestyles. One billion people are expected to suffer from myopia by 2020. Myopia is caused by excessive growth of the eye. Although the blurry vision caused by myopia can often be corrected with spectacles, the eye structure remains stretched and fragile, which can lead to irreversible vision loss. Myopia is complicated to study, because the vertebrate retina contains over 80 different types of neurons. In comparison, the invertebrate squid has evolved eyes with similar optics to ours, but with just one type of neuron. Thanks to convergent evolution, this makes squid a unique model to study the mechanisms of myopia. Squid eggs were collected off the New Zealand coast and raised in the lab under different coloured lights. As red light takes longer to focus than blue light, squid eyes grown in a red environment grew larger to remain in focus. This first invertebrate model of myopia shows that the squid eye can prevent myopia by staying in focus as it grows, and it achieves this with a much simpler retina.