Scientists are beginning to notice that more and more species are missing an essential vitamin, one that is crucial for their survival. Hosted by: Stefan Chin SciShow has a spinoff podcast! It's called SciShow Tangents. Check it out at http://www.scishowtangents.org/ ---------- Support SciShow by becoming a patron on Patreon: https://www.patreon.com/scishow ---------- Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever: Silas Emrys, Drew Hart, Jeffrey Mckishen, James Knight, Christoph Schwanke, Jacob, Matt Curls, Christopher R Boucher, Eric Jensen, Adam Brainard, Nazara, GrowingViolet, Ash, Laura Sanborn, Sam Lutfi, Piya Shedden, KatieMarie Magnone, charles george, Alex Hackman, Chris Peters, Kevin Bealer, Alisa Sherbow ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com/ Instagram: http://instagram.com/thescishow ---------- Sources: https://doi.org/10.1016/S0380-1330(95)71102-9 https://doi.org/10.1038/srep38821 https://doi.org/10.1038/s41598-019-46422-2 https://doi.org/10.1073/pnas.1208755109 https://doi.org/10.1038/s41558-020-00918-2 https://pubmed.ncbi.nlm.nih.gov/23560604/ https://doi.org/10.1577/H03-081.1 https://pubs.er.usgs.gov/publication/70192264 https://doi.org/10.1371/journal.pone.0227714 https://doi.org/10.3389/fmars.2020.00589 https://doi.org/10.7589/0090-3558-19.3.248 https://doi.org/10.13140/RG.2.2.15585.74083 https://www.su.se/english/research/unravelling-the-mystery-of-dead-elk-in-southern-sweden-1.137132 https://pubmed.ncbi.nlm.nih.gov/17423563/ https://doi.org/10.1016/S0098-8472(01)00125-3 https://doi.org/10.2307/2404985 https://doi.org/10.1371/journal.pone.0227201 https://pubmed.ncbi.nlm.nih.gov/30327388/ https://www.fisheries.noaa.gov/feature-story/researchers-probe-deaths-central-valley-chinook-possible-ties-ocean-changes Images https://www.istockphoto.com/photo/great-lakes-3d-render-topographic-map-color-gm1020385600-274139186 https://www.storyblocks.com/video/stock/european-sprat-sprattus-sprattus-also-known-as-bristling-brisling-or-skipper-is-a-small-herring-like-marine-fish-b0sz8shtitim6yls https://commons.wikimedia.org/wiki/File:Mallotus_villosus.gif https://www.storyblocks.com/video/stock/moscow-russia---may-22-2017-aerial-shot-of-city-highway-traffic-jam-on-a-car-bridge-city-business-district-4k-clip-bhyzmmzwwj31z46k9 https://www.storyblocks.com/video/stock/wheat-grains-in-a-sack-rtxxs9hypkcnhw9fp https://commons.wikimedia.org/wiki/File:Saffron_Cod_Juveniles.jpg https://commons.wikimedia.org/wiki/File:California_Mussels_002.jpg https://en.wikipedia.org/wiki/King_eider#/media/File:King_Eider_(Somateria_spectabilis)_(13667616745).jpg https://commons.wikimedia.org/wiki/File:Atlantic_salmon_Atlantic_fish.jpg https://commons.wikimedia.org/wiki/File:Marinesnow-splash.jpg https://www.istockphoto.com/photo/remote-camping-on-playa-el-coyote-baja-california-sur-mexico-gm694592194-128359055 https://www.istockphoto.com/photo/seagull-gm183038445-14294832 https://www.istockphoto.com/photo/mussells-in-a-tidal-pool-gm118735485-11653262 https://www.istockphoto.com/photo/crocodile-gm171586404-22028519 https://www.istockphoto.com/photo/neuronal-network-with-electrical-activity-of-neuron-cells-3d-rendering-illustration-gm1216658919-354860008 https://www.istockphoto.com/photo/vintage-photo-products-and-ingredients-containing-vitamin-b1-and-dietary-fiber-gm651169780-118251575 https://www.istockphoto.com/photo/vitamin-b1-thiamine-medical-bottles-with-pills-and-spray-bottle-3d-rendering-gm1013264928-272864445 https://www.nature.com/articles/srep38821#rightslink https://en.wikipedia.org/wiki/File:Lake_trout_fishes_salvelinus_namaycush.jpg https://www.storyblocks.com/video/stock/ponds-for-rearing-trout-in-fisheries-rpvp_t0ripy6x0sd https://www.storyblocks.com/video/stock/ws-fishermen-dumping-fish-into-containers--cornwall-england-uk-hur3kp3xeiwmt5r7t https://www.storyblocks.com/video/stock/agricultural-sprayer-watering-farming-field-agriculture-spraying-machine-working-on-agricultural-field-farmer-care-plants-pesticides-spraying-rbo8c64ggjbbqv2oh