Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup

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usa-input-error-message selection-validation-message"> Name must be less than 100 characters </div> </div> <div class="action-panel-control-wrap existing-collections-controls"> <label for="collections-action-panel-add-to-existing" class="action-panel-label"> Choose a collection: </label> <select id="collections-action-panel-add-to-existing" class="action-panel-selector collections-action-add-to-existing" data-ga-category="save_share" data-ga-action="select_collection" data-ga-label="($('#collections-action-add-to-existing').val() === 'Favorites') ? 'Favorites' : 'non_favorites_collection'"> </select> <div class="collections-retry-load-on-error usa-input-error-message selection-validation-message"> Unable to load your collection due to an error<br> <a href="#">Please try again</a> </div> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Adding..." data-pinger-ignore data-ga-category="save_share" data-ga-action="collections" data-ga-label="add"> Add </button> <button class="action-panel-cancel" aria-label="Close 'Add to Collections' panel" ref="linksrc=close_collections_panel" aria-controls="collections-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="collections" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="bibliography-action-panel" class="bibliography-action-panel action-panel in-progress-dots-panel" aria-hidden="true" data-bibliography-open-panel-enabled="false" data-bibliography-open-panel-url-hash="#open-bibliography-panel"> <div class="inner-wrap"> <h3 class="action-panel-heading"> Add to My Bibliography </h3> <form id="bibliography-action-panel-form" class="bibliography-action-panel-form action-panel-content action-form action-panel-smaller-selectors" data-add-to-bibliography-max-amount="100" data-add-to-bibliography-batch-size="10" data-bibliography-delegates-url="/list-bibliography-delegates/" data-add-to-bibliography-url="/add-to-bibliography/" data-get-article-ids-by-search-url="/get-article-ids-by-search/" data-mybib-root-url="https://www.ncbi.nlm.nih.gov/myncbi/collections/mybibliography/"> <input type="hidden" name="csrfmiddlewaretoken" value="ZviLOjPnb1HDumWss8UQLJdK0RnJBmrZxk6Th8fIOH0pH1rtt2aP9NZwdvEl1ctI"> <div class="action-panel-control-wrap bibliographies-controls"> <div class="choice-group"> <ul class="bibliographies-action-add radio-group-items"> <li> <input name="bibliography" id="my-bibliography" class="my-bibliography" type="radio" checked/> <label for="my-bibliography">My Bibliography</label> </li> </ul> </div> </div> <div class="bibliographies-retry-load-on-error usa-input-error-message selection-validation-message"> Unable to load your delegates due to an error<br> <a href="#">Please try again</a> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Adding..." data-pinger-ignore> Add </button> <button class="action-panel-cancel" aria-label="Close 'Add to bibliography' panel" ref="linksrc=close_bibliography_panel" aria-controls="bibliography-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="mybib" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="saved-search-action-panel" class="saved-search-action-panel action-panel " aria-hidden="true" data-saved-search-open-panel-enabled="false" data-saved-search-open-panel-url-hash="#open-saved-search-panel"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Your saved search </h2> <form id="saved-search-action-panel-form" class="saved-search-action-panel-form action-panel-content action-form" data-create-saved-search-url="/create-saved-search/" data-try-search-terms-url="/try-search-term/" data-saved-search-root-url="https://www.ncbi.nlm.nih.gov/myncbi/searches/"> <input type="hidden" name="csrfmiddlewaretoken" value="ZviLOjPnb1HDumWss8UQLJdK0RnJBmrZxk6Th8fIOH0pH1rtt2aP9NZwdvEl1ctI"> <div class="action-panel-control-wrap"> <label for="saved-search-name" class="action-panel-label saved-search-name-label required-field-asterisk"> Name of saved search: </label> <input maxlength="200" type="text" name="saved-search-name" id="saved-search-name" class="saved-search-name" value="" required pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/"> </div> <div class="action-panel-control-wrap"> <label for="saved-search-term" class="action-panel-label required-field-asterisk"> Search terms: </label> <textarea name="saved-search-term" id="saved-search-term" class="saved-search-term" required></textarea> </div> <div class="test-search-term-wrap"> <a href="#" class="try-search-term">Test search terms</a> </div> <div class="choice-group action-panel-extra-margin-top"> <span class="action-panel-label" id="fieldset-label"> Would you like email updates of new search results? </span> <fieldset id="saved-search-alert" aria-describedby="fieldset-label"> <legend class="usa-sr-only">Saved Search Alert Radio Buttons</legend> <ul class="radio-group-items"> <li> <input type="radio" id="saved-search-alert-yes" class="saved-search-alert-yes" name="saved-search-alert" value="yes" checked> <label for="saved-search-alert-yes" class="action-panel-label">Yes</label> </li> <li> <input aria-label="No radio input" type="radio" id="saved-search-alert-no" class="saved-search-alert-no" name="saved-search-alert" value="no"> <label for="saved-search-alert-no" class="action-panel-label">No</label> </li> </ul> </fieldset> </div> <div class="alert-schedule-wrap"> <div class="action-panel-control-wrap"> <label class="action-panel-label"> Email: </label> <span aria-label="Email address" id="saved-search-email" class="action-panel-label"><span class="action-panel-label-bold"></span> (<a class="myncbi-account-settings" href="https://www.ncbi.nlm.nih.gov/account/settings/">change</a>)</span> </div> <div class="action-panel-control-wrap action-panel-extra-margin-top"> <label for="saved-search-frequency" class="action-panel-label"> Frequency: </label> <select id="saved-search-frequency" class="no-border-panel-selector saved-search-frequency"> <option value="monthly">Monthly</option> <option value="weekly">Weekly</option> <option value="daily">Daily</option> </select> </div> <div class="action-panel-control-wrap saved-search-monthly-additional"> <label for="saved-search-monthly-on-day" class="action-panel-label"> Which day? </label> <select id="saved-search-monthly-on-day" class="no-border-panel-selector"> <option value="Sunday">The first Sunday</option> <option value="Monday">The first Monday</option> <option value="Tuesday">The first Tuesday</option> <option value="Wednesday">The first Wednesday</option> <option value="Thursday">The first Thursday</option> <option value="Friday">The first Friday</option> <option value="Saturday">The first Saturday</option> <option value="day">The first day</option> <option value="weekday">The first weekday</option> </select> </div> <div class="action-panel-control-wrap saved-search-weekly-additional"> <label for="saved-search-weekly-on-day" class="action-panel-label"> Which day? </label> <select id="saved-search-weekly-on-day" class="no-border-panel-selector saved-search-weekly-on-day"> <option value="Sunday">Sunday</option> <option value="Monday">Monday</option> <option value="Tuesday">Tuesday</option> <option value="Wednesday">Wednesday</option> <option value="Thursday">Thursday</option> <option value="Friday">Friday</option> <option value="Saturday">Saturday</option> </select> </div> <div class="action-panel-control-wrap"> <label for="saved-search-report" class="action-panel-label"> Report format: </label> <select id="saved-search-report" class="no-border-panel-selector saved-search-report"> <option value="DocSum">Summary</option> <option value="DocSumText">Summary (text)</option> <option value="Abstract">Abstract</option> <option value="AbstractText">Abstract (text)</option> <option value="MEDLINE">PubMed</option> </select> </div> <div class="action-panel-control-wrap"> <label for="saved-search-amount" class="action-panel-label"> Send at most: </label> <select id="saved-search-amount" class="no-border-panel-selector saved-search-amount"> <option value="1">1 item</option> <option value="5" selected>5 items</option> <option value="10">10 items</option> <option value="20">20 items</option> <option value="50">50 items</option> <option value="100">100 items</option> <option value="200">200 items</option> </select> </div> <div> <input type="checkbox" id="saved-search-send-if-no-result" class="saved-search-send-if-no-result" name="saved-search-send-if-no-result"> <label for="saved-search-send-if-no-result" class="action-panel-label smaller-checkbox"> Send even when there aren't any new results </label> </div> <div class="action-panel-control-wrap option-text-in-email-wrap"> <label for="saved-search-email-text" class="action-panel-label"> Optional text in email: </label> <textarea name="saved-search-email-text" id="saved-search-email-text" class="saved-search-email-text"></textarea> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Saving..." data-ga-category="save_share" data-ga-action="alert" data-ga-label="save"> Save </button> <button class="action-panel-cancel" aria-label="Close 'Your saved search' panel" ref="linksrc=close_saved_search_panel" aria-controls="saved-search-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="alert" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="citation-manager-action-panel" class="citation-manager-action-panel action-panel" aria-hidden="true"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Create a file for external citation management software </h2> <form id="citation-manager-action-panel-form" class="action-panel-content action-form" action="/results-export-ids/" data-by-search-action="/results-export-search-data/" data-by-ids-action="/results-export-ids/" method="post" data-by-search-method="post" data-by-ids-method="post"> <input type="hidden" name="csrfmiddlewaretoken" value="ZviLOjPnb1HDumWss8UQLJdK0RnJBmrZxk6Th8fIOH0pH1rtt2aP9NZwdvEl1ctI"> <input name="results-format" type="hidden" value="pubmed"/> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Sending..." data-ga-category="save_share" data-ga-action="citation_manager" data-ga-label="save"> Create file </button> <button class="action-panel-cancel" aria-label="Close 'Send citations to citation manager' panel" ref="linksrc=close_citation_manager_panel" aria-controls="citation-manager-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="citation_manager" data-ga-label="cancel"> Cancel </button> </div> </form> </div> </div> <div id="rss-action-panel" class="rss-action-panel action-panel " aria-hidden="true"> <div class="inner-wrap"> <h2 class="action-panel-heading"> Your RSS Feed </h2> <form id="rss-action-panel-form" class="rss-action-panel-form action-panel-content action-form" data-create-rss-feed-url="/create-rss-feed-url/" data-search-form-term-value=""> <input type="hidden" name="csrfmiddlewaretoken" value="ZviLOjPnb1HDumWss8UQLJdK0RnJBmrZxk6Th8fIOH0pH1rtt2aP9NZwdvEl1ctI"> <div class="action-panel-control-wrap"> <label for="rss-name" class="action-panel-label required-field-asterisk"> Name of RSS Feed: </label> <input maxlength="200" placeholder="Name" type="text" name="rss-name" id="rss-name" class="rss-name" value='' required pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/"> </div> <div class="rss-limit-wrap"> <div class="action-panel-control-wrap action-panel-extra-margin-top"> <label for="rss-limit" class="action-panel-label"> Number of items displayed: </label> <select id="rss-limit" class="no-border-panel-selector rss-limit"> <option value="5">5</option> <option value="10">10</option> <option value="15" selected="selected">15</option> <option value="20">20</option> <option value="50">50</option> <option value="100">100</option> </select> </div> </div> <div class="action-panel-actions"> <button class="action-panel-submit" type="submit" data-loading-label="Creating..." data-ga-category="save_share" data-ga-action="alert" data-ga-label="save"> Create RSS </button> <button class="action-panel-cancel" aria-label="Close 'Your RSS' panel" ref="linksrc=close_rss_panel" aria-controls="rss-action-panel" aria-expanded="false" data-ga-category="save_share" data-ga-action="alert" data-ga-label="cancel"> Cancel </button> </div> <div class="action-panel-control-wrap rss-link-copy-wrap"> <label for="rss-link" class="usa-sr-only">RSS Link</label> <input placeholder="Your RSS Feed Link" type="text" name="rss-link" id="rss-link" class="rss-link" title="RSS Link"> <button type="button" disabled class="rss-link-copy-button disabled" data-ga-category="save_share" data-ga-action="rss" data-ga-label="copy"> Copy </button> </div> </form> </div> </div> </div> </div> <div class="article-page" id="article-page" data-article-pmid="18026166"> <aside class="page-sidebar"> <div class="inner-wrap"> <div class="full-text-links"> <div class="full-view"> <h3 class="title"> Full text links </h3> <div class="full-text-links-list"> <a class="link-item dialog-focus" 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required-field-asterisk"> Name your collection: </label><input type="text" name="add-to-new-collection" id="collections-action-dialog-add-to-new" class="collections-action-add-to-new" pattern="[^"&=<>\/]*" title="The following characters are not allowed in the Name field: "&=<>/" maxlength="100" data-ga-category="collections_button" data-ga-action="create_collection" data-ga-label="non_favorties_collection"><div class="collections-new-name-too-long usa-input-error-message selection-validation-message"> Name must be less than 100 characters </div></div><div class="action-panel-control-wrap existing-collections-controls"><label for="collections-action-dialog-add-to-existing" class="action-panel-label"> Choose a collection: </label><select id="collections-action-dialog-add-to-existing" class="action-panel-selector collections-action-add-to-existing" data-ga-category="collections_button" data-ga-action="select_collection" data-ga-label="($('.collections-action-add-to-existing').val() === 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Neuroscience"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Nat+Rev+Neurosci%22%5Bjour%5D&sort=date&sort_order=desc" data-href="/?term=%22Nat+Rev+Neurosci%22%5Bjour%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_journal_name_link&journal_abbrev=Nat Rev Neurosci" data-ga-category="search" data-ga-action="journal_link" data-ga-label="Nat Rev Neurosci"> Search in PubMed </a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link" ref ="linksrc=search_in_nlm_catalog_link" href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22Nat+Rev+Neurosci%22%5BTitle+Abbreviation%5D" data-ga-category="search_catalog" data-ga-action="journal_link" data-ga-label="Nat Rev Neurosci"> Search in NLM Catalog </a></li><li><a class="add-to-search-link dropdown-block-link" ref ="linksrc=add_to_search_link" role="button" data-search-term='"Nat Rev Neurosci"[jour]' data-ga-category="search" data-ga-action="add_to_search" data-ga-label='"Nat Rev Neurosci"[jour]' href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2007 Dec;8(12):960-76.</span> </div> <span class="citation-doi"> doi: 10.1038/nrn2283. </span> </div> <h1 class="heading-title"> Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup </h1> <div class="inline-authors"> <div class="authors"> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Lamb+TD&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Trevor D Lamb">Trevor D Lamb</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Australian National University, Division of Neuroscience, The John Curtin School of Medical Research, Garran Road, The Australian National University, Canberra, Australian Capital Territory 2600, Australia. Trevor.Lamb@anu.edu.au" href="#full-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Collin+SP&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Shaun P Collin">Shaun P Collin</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Pugh+EN+Jr&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Edward N Pugh Jr">Edward N Pugh Jr</a></span> </div> </div> </div> <div class="short-article-details"> Affiliations <button class="more-details" id="toggle-authors" data-alt-text="Collapse" aria-controls="expanded-authors" aria-expanded="false" data-pinger-ignore data-fetch-url="/18026166/long-authors/" data-id-prefix=""> <span class="title"> Expand </span> </button> </div> <div class="extended-article-details" id="expanded-authors" aria-hidden="true"> <div class="expanded-authors" id="full-view-expanded-authors"> <div class="affiliations"> <h3 class="title"> Affiliation </h3> <ul class="item-list"> <li data-affiliation-id="full-view-affiliation-1" id="full-view-affiliation-1" ><sup class="key">1</sup> Australian National University, Division of Neuroscience, The John Curtin School of Medical Research, Garran Road, The Australian National University, Canberra, Australian Capital Territory 2600, Australia. Trevor.Lamb@anu.edu.au</li> </ul> </div> </div> </div> <ul class="identifiers" id="full-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" title="PubMed ID">18026166</strong> </span> </li> <li> <span class="identifier pmc"> <span class="id-label"> PMCID: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=PMC3143066&id_type=PMC" href="https://pmc.ncbi.nlm.nih.gov/articles/PMC3143066/" data-ga-category="full_text" data-ga-action="PMCID" > PMC3143066 </a> </span> </li> <li> <span class="identifier doi"> <span class="id-label"> DOI: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=10.1038/nrn2283&id_type=DOI" href="https://doi.org/10.1038/nrn2283" data-ga-category="full_text" data-ga-action="DOI" > 10.1038/nrn2283 </a> </span> </li> </ul> <div class="in-clipboard-label " hidden> Item in Clipboard </div> </div> <div class="short-view" id="short-view-heading"> <div class="publication-type" >Review</div> <h1 class="heading-title"> Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup </h1> <div class="short-citation"> <span class="authors-list"> <span class="authors-list-item "><span class="full-name">Trevor D Lamb</span><span class="citation-separator"> et al.</span></span> </span> <span class="citation-journal"> Nat Rev Neurosci<span class="citation-separator">.</span> </span> <span class="date"> <span class="citation-year">2007 Dec</span><span class="citation-separator">.</span> </span> </div> <div class="more-article-details-section with-display-settings"> <button class="more-article-details" id="toggle-article-details" data-alt-text="Hide details" ref="linksrc=toggle_article_details" aria-controls="full-article-details" aria-expanded="false" data-fetch-url="/18026166/long-authors/" data-id-prefix=""> <span class="title">Show details</span> </button> <div class="display-options" data-format-key="format" data-default-format-value="abstract" data-current-format-value="abstract" role="region"> <button class="trigger usa-button" title="Change format" data-ga-category="display_options" data-ga-action="display_options_dialog"> <span class="button-label">Display options</span> </button> <div class="dropdown" hidden> <div class="title"> Display options </div> <div class="content"> <div class="format-container"> <span class="option-label"> Format </span> <select name="format" data-initial-value="abstract" aria-label="Display format" id="mobile-display-format"> <option value="abstract">Abstract</option> <option value="pubmed">PubMed</option> <option value="pmid">PMID</option> </select> </div> </div> </div> </div> </div> <div class="extended-article-details" id="full-article-details" aria-hidden="true"> <div class="article-citation"> <div class="article-source"> <div class="journal-actions dropdown-block"><button id="short-view-journal-trigger" class="journal-actions-trigger trigger" ref="linksrc=journal_actions_btn" title="Nature reviews. 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Neuroscience"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Nat+Rev+Neurosci%22%5Bjour%5D&sort=date&sort_order=desc" data-href="/?term=%22Nat+Rev+Neurosci%22%5Bjour%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_journal_name_link&journal_abbrev=Nat Rev Neurosci" data-ga-category="search" data-ga-action="journal_link" data-ga-label="Nat Rev Neurosci"> Search in PubMed </a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link" ref ="linksrc=search_in_nlm_catalog_link" href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22Nat+Rev+Neurosci%22%5BTitle+Abbreviation%5D" data-ga-category="search_catalog" data-ga-action="journal_link" data-ga-label="Nat Rev Neurosci"> Search in NLM Catalog </a></li><li><a class="add-to-search-link dropdown-block-link" ref ="linksrc=add_to_search_link" role="button" data-search-term='"Nat Rev Neurosci"[jour]' data-ga-category="search" data-ga-action="add_to_search" data-ga-label='"Nat Rev Neurosci"[jour]' href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2007 Dec;8(12):960-76.</span> </div> <span class="citation-doi"> doi: 10.1038/nrn2283. </span> </div> <div class="expanded-authors" id="short-view-expanded-authors"> <div class="authors"> <h3 class="title"> Authors </h3> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Lamb+TD&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Trevor D Lamb">Trevor D Lamb</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Australian National University, Division of Neuroscience, The John Curtin School of Medical Research, Garran Road, The Australian National University, Canberra, Australian Capital Territory 2600, Australia. Trevor.Lamb@anu.edu.au" href="#short-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Collin+SP&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Shaun P Collin">Shaun P Collin</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Pugh+EN+Jr&cauthor_id=18026166" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Edward N Pugh Jr">Edward N Pugh Jr</a></span> </div> </div> <div class="affiliations"> <h3 class="title"> Affiliation </h3> <ul class="item-list"> <li data-affiliation-id="short-view-affiliation-1" id="short-view-affiliation-1" ><sup class="key">1</sup> Australian National University, Division of Neuroscience, The John Curtin School of Medical Research, Garran Road, The Australian National University, Canberra, Australian Capital Territory 2600, Australia. Trevor.Lamb@anu.edu.au</li> </ul> </div> </div> <ul class="identifiers" id="short-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" title="PubMed ID">18026166</strong> </span> </li> <li> <span class="identifier pmc"> <span class="id-label"> PMCID: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=PMC3143066&id_type=PMC" href="https://pmc.ncbi.nlm.nih.gov/articles/PMC3143066/" data-ga-category="full_text" data-ga-action="PMCID" > PMC3143066 </a> </span> </li> <li> <span class="identifier doi"> <span class="id-label"> DOI: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=10.1038/nrn2283&id_type=DOI" href="https://doi.org/10.1038/nrn2283" data-ga-category="full_text" data-ga-action="DOI" > 10.1038/nrn2283 </a> </span> </li> </ul> <div class="in-clipboard-label " hidden> Item in Clipboard </div> </div> </div> </header> <div class="actions-buttons inline"><div class="inner-wrap"><button class="full-text-links-button full-text-links-dialog-trigger" title="Open dialog with full text links" ref="linksrc=full_text_links"> Full text links </button><button class="citation-button citation-dialog-trigger" aria-label="Open dialog with citation text in different styles" data-ga-category="save_share" data-ga-action="cite" data-ga-label="open" data-all-citations-url="/18026166/citations/" data-citation-style="nlm" data-pubmed-format-link="/18026166/export/"><span class="button-label">Cite</span></button><button class="more-actions-button more-actions-dialog-trigger" title="Open dialog with more actions to take" ref="linksrc=more_actions_btn"></button><div class="display-options" data-format-key="format" data-default-format-value="abstract" data-current-format-value="abstract" role="region"><button class="trigger usa-button" title="Change format" data-ga-category="display_options" data-ga-action="display_options_dialog"><span class="button-label">Display options</span></button><div class="dropdown" hidden><div class="title"> Display options </div><div class="content"><div class="format-container"><span class="option-label"> Format </span><select name="format" data-initial-value="abstract" aria-label="Display format" id="inline-actions-display-format"><option value="abstract">Abstract</option><option value="pubmed">PubMed</option><option value="pmid">PMID</option></select></div></div></div></div></div></div> <div class="abstract" id="abstract"> <h2 class="title"> Abstract </h2> <div class="abstract-content selected" id="eng-abstract"> <p> Charles Darwin appreciated the conceptual difficulty in accepting that an organ as wonderful as the vertebrate eye could have evolved through natural selection. He reasoned that if appropriate gradations could be found that were useful to the animal and were inherited, then the apparent difficulty would be overcome. Here, we review a wide range of findings that capture glimpses of the gradations that appear to have occurred during eye evolution, and provide a scenario for the unseen steps that have led to the emergence of the vertebrate eye. </p> </div> </div> <p class="disclaimer" id="disclaimer"> <a href="/disclaimer/" target="_blank" ga_category="literature_resources" ga_action="disclaimer_link" ga_label="under_abstract">PubMed Disclaimer</a> </p> <div class="figures" id="figures"> <h2 class="title"> Figures </h2> <div class="figures-list" id="slides-container" itemscope itemtype="http://schema.org/ImageGallery"> <figure class="figure-item " itemscope itemtype="http://schema.org/ImageObject" itemprop="associatedMedia" data-slide-index="0" data-label-slug="figure-1"> <a class="figure-link" href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/69c073bba70c/nihms309801f1.jpg" itemprop="contentUrl" aria-describedby="figure-caption-0" role="button" data-image-width="615" data-image-height="517" data-image-alt="Figure 1" data-pmc-id="PMC3143066" data-figure-id="F1"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-0" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/539a80a9fb32/nihms309801f1.gif" alt="Figure 1" /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="615"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="517"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 1. The origin of vertebrates </p> </strong> <div class="figure-caption-contents"><p> The… </p></div> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 1. The origin of vertebrates </p> </strong> <div class="figure-caption-contents"><p> The evolution of jawed vertebrates is illustrated against an… </p></div> </div> <figcaption id="figure-caption-0" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 1. The origin of vertebrates </strong> <div class="figure-caption-contents">The evolution of jawed vertebrates is illustrated against an approximate time-scale of millions of years ago (Mya). The taxa considered in this Review are indicated with an asterisk and are accompanied by schematics and diagrams of the ‘eye’ region. The earliest chordates, represented by extant cephalochordates and tunicates, are thought to have appeared around 550 Mya. Jawless craniates (agnathans) were present in the early Cambrian, by 525 Mya, and a time of 530 Mya has been indicated for their presumed first appearance. As elaborated on in BOX 1, there is considerable controversy as to whether myxiniformes (solely represented by extant hagfish) diverged before or after the separation of lampreys from jawed vertebrates (shown as dashed black and grey lines). Numerous lines of jawless fish evolved between 500 and 430 Mya ago, although none have survived to the present day. The first jawed vertebrate arose around 430 Mya, and this line is represented today by cartilagenous fish, bony fish and tetrapods. Six ‘stages of interest’ in vertebrate eye evolution correspond to the time intervals between the divergence of important surviving taxa. This diagram does not include the evolutionary changes that have occurred in the last 400 million years. The presented timeline is based primarily on evidence from the fossil record; see REFS ,,,,,,–. The schematics are modified, with permission, from REF. © (1996) Oxford University Press (lancelet, sea squirt, hagfish and lamprey) and REF. © (2004) Academic Press (jawed vertebrate). The eye images are reproduced, with permission, from the following references: lancelet, REF. © BIODIDAC (1996) University of California Museum of Paleontology; sea squirt, REF. © (2006) Blackwell Publishing; hagfish, REF. © (2006) Australian Museum. Lamprey and jawed vertebrate eye images are courtesy of G. Westhoff and S. P. Collin).</div> </figcaption> </figure> <figure class="figure-item " itemscope itemtype="http://schema.org/ImageObject" itemprop="associatedMedia" data-slide-index="1" data-label-slug="figure-2"> <a class="figure-link" href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/84deaca81864/nihms309801f2.jpg" itemprop="contentUrl" aria-describedby="figure-caption-1" role="button" data-image-width="729" data-image-height="602" data-image-alt="Figure 2" data-pmc-id="PMC3143066" data-figure-id="F2"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-1" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/420ce0e674f4/nihms309801f2.gif" alt="Figure 2" /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="729"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="602"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 2. The structure of ciliary photoreceptors… </p> </strong> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 2. The structure of ciliary photoreceptors at various stages of chordate/vertebrate evolution </p> </strong> <div class="figure-caption-contents"><p> The middle… </p></div> </div> <figcaption id="figure-caption-1" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 2. The structure of ciliary photoreceptors at various stages of chordate/vertebrate evolution </strong> <div class="figure-caption-contents">The middle row shows schematic diagrams of the entire photoreceptor; the top and bottom rows show electron micrographs of the outer segment and the synaptic terminal, respectively. Note the gradual transition towards a highly organized laminar structure in the outer segment and the appearance of ribbons in the synaptic terminal. The schematics are modified with permission from, and the micrographs are reproduced with permission from, the following references: ascidian larva (schematic), REF. © (1971) Springer Verlag; ascidian larva (outer segment), REF. © (1971) Springer Verlag; hagfish eye, REF. © (1971) Springer Verlag; larval lamprey pineal, REF. © (1981) American Physiological Society; adult lamprey retina, REF. © (2006) Science Publishers; gnathostome retina (outer segment), REF. © (1980) Wiley-Liss; gnathostome retina (schematic), REF. © (1997) Springer Verlag; gnathostome retina (synaptic terminal), REF. © (1975) Rockerfeller University Press.</div> </figcaption> </figure> <figure class="figure-item " itemscope itemtype="http://schema.org/ImageObject" itemprop="associatedMedia" data-slide-index="2" data-label-slug="figure-3"> <a class="figure-link" href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/696d30815c64/nihms309801f3.jpg" itemprop="contentUrl" aria-describedby="figure-caption-2" role="button" data-image-width="605" data-image-height="406" data-image-alt="Figure 3" data-pmc-id="PMC3143066" data-figure-id="F3"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-2" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/8b3798f3d362/nihms309801f3.gif" alt="Figure 3" /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="605"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="406"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 3. The evolution of vertebrate opsins </p> </strong> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 3. The evolution of vertebrate opsins </p> </strong> <div class="figure-caption-contents"><p> On the left of the main figure is… </p></div> </div> <figcaption id="figure-caption-2" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 3. The evolution of vertebrate opsins </strong> <div class="figure-caption-contents">On the left of the main figure is a dendrogram of the major opsin classes that are relevant to the evolution of the vertebrate eye. Before the separation of protostomes and deuterostomes, the primordial opsin had already diverged into three main classes: rhabdomeric opsins, which are characteristic of protostome rhabdomeric photoreceptors (see upper photoreceptor schematic) but are also found in melanopsin-containing vertebrate retinal ganglion cells; ‘photoisomerase’ opsins, such as retinal G-protein-coupled receptor (RGR) opsin and peropsin, which may in fact be G-protein-coupled receptors; and ciliary opsins (see lower photoreceptor schematic), which are characteristic of those photoreceptors in which the pigment-containing region is an expansion of the membrane of a cilium. Vertebrate retinal opsins are represented by the lowermost six rows in the diagram. The primordial retinal opsin of vertebrates diverged into long-wavelength sensitive (LWS) and short-wavelength-sensitive (SWS) branches, and then the latter split into several sub-groups: SWS1, SWS2 and Rh2/RhB, each of which is associated with cone-like photoreceptors. The Rh1 pigment of jawed vertebrates (bottom line) seems to represent the most recent development among these classes, and is expressed in vertebrate rod photoreceptors. A separate class of rod, the ‘green rod’ of non-mammalian vertebrates, uses the SWS2 pigment that is also present in the blue-sensitive cones of these species. On the right of the main figure are presumed classes of G-protein coupling mechanism, residues at four important locations (in the numbering system for bovine rhodopsin; blue and green shading highlights residue similarity; pink shading highlights a chloride-binding site), and the regional expression of the opsins in vertebrate tissues. AC, amacrine cell; GC, ganglion cell; HC, horizontal cell; RPE, retinal pigment epithelium; VA, vertebrate ancient. The dendrogram is a composite, based on data from REFS ,,,, and elsewhere. The schematic of the rhabdomeric photoreceptor is modified, with permission, from REF. © (2001) Macmillan Publishers Ltd. The schematic of the ciliary photoreceptor is modified, with permission, from REF. © (2003) MIT Press.</div> </figcaption> </figure> <figure class="figure-item " itemscope itemtype="http://schema.org/ImageObject" itemprop="associatedMedia" data-slide-index="3" data-label-slug="figure-4"> <a class="figure-link" href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/fcf9cbe99250/nihms309801f4.jpg" itemprop="contentUrl" aria-describedby="figure-caption-3" role="button" data-image-width="603" data-image-height="676" data-image-alt="Figure 4" data-pmc-id="PMC3143066" data-figure-id="F4"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-3" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/b20b712af204/nihms309801f4.gif" alt="Figure 4" /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="603"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="676"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 4. Development of the vertebrate eye… </p> </strong> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 4. Development of the vertebrate eye cup </p> </strong> <div class="figure-caption-contents"><b> a </b> | The neural plate is the…</div> </div> <figcaption id="figure-caption-3" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 4. Development of the vertebrate eye cup </strong> <div class="figure-caption-contents"><b>a</b> | The neural plate is the starting point for the development of the vertebrate eye cup. <b>b</b> | The neural plate folds upwards and inwards. <b>c</b> | The optic grooves evaginate. <b>d</b> | The lips of the neural folds approach each other and the optic vesicles bulge outwards. <b>e</b> | After the lips have sealed the neural tube is pinched off. At this stage the forebrain grows upwards and the optic vesicles continue to balloon outwards: they contact the surface ectoderm and induce the lens placode. <b>f</b> | The optic vesicle now invaginates, so that the future retina is apposed to the future retinal pigment epithelium (RPE), and the ventricular space that was between them disappears. Developing retinal ganglion cells send axons out across the retinal surface. The surface ectoderm at the lens placode begins to form the lens pit. This section is midline in the right eye, through the choroid fissure, so only the upper region of the retina and the RPE are visible. <b>g</b> | The eye cup grows circumferentially, eventually sealing over the choroidal fissure and enclosing the axons of the optic nerve (as well as the hyaloid/retinal vessels; not shown). The ectodermal tissue continues to differentiate and eventually forms the lens. This figure is animated online (see Supplementary information S1).</div> </figcaption> </figure> <figure class="figure-item " itemscope itemtype="http://schema.org/ImageObject" itemprop="associatedMedia" data-slide-index="4" data-label-slug="figure-5"> <a class="figure-link" href="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/5bafb35a820d/nihms309801f5.jpg" itemprop="contentUrl" aria-describedby="figure-caption-4" role="button" data-image-width="604" data-image-height="557" data-image-alt="Figure 5" data-pmc-id="PMC3143066" data-figure-id="F5"> <img class="figure-thumb" itemprop="thumbnail" id="article-image-4" src="https://cdn.ncbi.nlm.nih.gov/pmc/blobs/732f/3143066/5f3063039df8/nihms309801f5.gif" alt="Figure 5" /> </a> <meta itemprop="width" itemtype="http://schema.org/ImageObject" content="604"> <meta itemprop="height" itemtype="http://schema.org/ImageObject" content="557"> <div class="figure-caption figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="caption" aria-hidden="true"> <div class="caption-wrap"> <strong class="figure-label"> <p> Figure 5. The development of retinal neurons… </p> </strong> </div> </div> <div class="figure-caption-medium figure-caption-text" aria-hidden="true"> <strong class="figure-label"> <p> Figure 5. The development of retinal neurons and circuitry </p> </strong> <div class="figure-caption-contents"><b> a </b> | The cell cycle in…</div> </div> <figcaption id="figure-caption-4" class="figure-caption-full figure-caption-text" itemtype="http://schema.org/ImageObject" itemprop="description"> <strong class="figure-label"> Figure 5. The development of retinal neurons and circuitry </strong> <div class="figure-caption-contents"><b>a</b> | The cell cycle in the vertebrate retina. The soma of a replicating cell migrates between the outer (ventricular) surface, where mitosis (M) occurs, and the inner (vitread) surface. <b>b</b> | The sequential birth of cell classes in the vertebrate retina, with timings indicated for the ferret in both post-natal weeks and caecal time (that is, the time relative to eye opening), which is probably a better comparator for other species. <b>c</b>–<b>e</b> | The maturation of neural connectivity in the retina<sup>,,</sup> (again, timings are for the ferret). <b>c</b> | Initially photoreceptors (which exhibit few adult morphological characteristics) send transient processes to the inner plexiform layer (IPL), where they make synaptic contacts with the two sub-laminae. <b>d</b> | Subsequently these processes retract, and developing bipolar cells insert themselves into the pathway between the photoreceptors and the inner nuclear layer (INL). <b>e</b> | At a later stage, the rod and cone photoreceptors develop inner segments (IS) and outer segments (OS). A, amacrine cell; B, bipolar cell; C, cone photoreceptor cell; G, ganglion cell; H, horizontal cell; ILM, inner limiting membrane; OLM, outer limiting membrane; OPL, outer plexiform layer; R, rod photoreceptor cell.</div> </figcaption> </figure> </div>  <div class="pswp figures-dialog" id="figures-dialog" tabindex="-1" role="dialog" aria-hidden="true" data-image-gallery-uid="article-figures" aria-label="Figures Dialog">  <div class="pswp__bg"></div>  <div class="pswp__scroll-wrap">  <div class="pswp__container"> <div class="pswp__item"></div> <div class="pswp__item"></div> <div class="pswp__item"></div> </div>  <div class="pswp__ui pswp__ui--hidden"> <div class="pswp__top-bar">  <div class="pswp__counter"></div> <button class="pswp__button pswp__button--close" title="Close (Esc)"></button> <button class="pswp__button pswp__button--share" title="Share"></button> <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button> <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button>   <div class="pswp__preloader"> <div class="pswp__preloader__icn"> <div class="pswp__preloader__cut"> <div class="pswp__preloader__donut"></div> </div> </div> </div> </div> <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap"> <div class="pswp__share-tooltip"></div> </div> <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)"> </button> <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)"> </button> <div class="pswp__caption"> <div class="pswp__caption__center"></div> </div> </div> </div> </div> <div class="figure-dialog-caption"> <div class="figure-caption-link-container"> <a class="figure-caption-link" href="#">See this image and copyright information in PMC</a> </div> <div class="figure-caption-center" data-expand-title="click to show full caption" data-collapse-title="click to hide full caption"> </div> <button class="figure-caption-toggle-btn" aria-label="show full caption" data-expand-text="show full caption" data-collapse-text="hide full caption">  </button> </div> </div> <div class="similar-articles" id="similar"> <h2 class="title"> Similar articles </h2> <ul class="articles-list" id="similar-articles-list"> <li class="full-docsum"> <div class="docsum-content" style="display:inline;"> <a class="docsum-title" href="/10220785/" ref="article_id=10220785&linksrc=similar_articles_link&ordinalpos=1" data-ga-category="similar_article" data-ga-action="10220785" data-ga-label=""> Photoreceptors sensitive for various wave-lengths in the pineal complex and retina of reptiles immunocytochemical localization of opsins. </a> <div class="docsum-citation full-citation"> <span class="docsum-authors full-authors">Debreceni K, Fejér Z, Szél A, Röhlich P, Görcs T, Vígh B.</span> <span class="docsum-authors short-authors">Debreceni K, et al.</span> <span class="docsum-journal-citation full-journal-citation">Neurobiology (Bp). 1998;6(4):463-5.</span> <span class="docsum-journal-citation short-journal-citation">Neurobiology (Bp). 1998.</span> <span class="citation-part">PMID: <span class="docsum-pmid">10220785</span></span> <span class="no-abstract spaced-citation-item citation-part">No abstract available.</span> </div> </div> </li> <li class="full-docsum"> <div class="docsum-content" style="display:inline;"> <a class="docsum-title" href="/23792002/" ref="article_id=23792002&linksrc=similar_articles_link&ordinalpos=2" data-ga-category="similar_article" data-ga-action="23792002" data-ga-label=""> Evolution of phototransduction, vertebrate photoreceptors and retina. </a> <div class="docsum-citation full-citation"> <span class="docsum-authors full-authors">Lamb TD.</span> <span class="docsum-authors short-authors">Lamb TD.</span> <span class="docsum-journal-citation full-journal-citation">Prog Retin Eye Res. 2013 Sep;36:52-119. doi: 10.1016/j.preteyeres.2013.06.001. 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data-pinger-ignore> Photoreceptor Cells, Vertebrate / physiology* </button><div id="keyword-actions-mesh-terms-major-8" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Photoreceptor Cells, Vertebrate / physiology*"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Photoreceptor+Cells%2C+Vertebrate%2Fphysiology%22%5BMAJR%5D&sort=date&sort_order=desc" data-href="/?term=%22Photoreceptor+Cells%2C+Vertebrate%2Fphysiology%22%5BMAJR%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Photoreceptor Cells, Vertebrate/physiology"[MAJR]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Photoreceptor Cells, Vertebrate / physiology*"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Photoreceptor+Cells%2C+Vertebrate" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Photoreceptor Cells, Vertebrate / physiology*"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Photoreceptor Cells, Vertebrate/physiology"[MAJR]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Photoreceptor Cells, Vertebrate/physiology"[MAJR]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major" aria-label="Toggle dropdown menu for keyword Retina / anatomy & histology*" tabindex="0" aria-controls="keyword-actions-mesh-terms-major-9" aria-expanded="false" data-pinger-ignore> Retina / anatomy & histology* </button><div id="keyword-actions-mesh-terms-major-9" class="keyword-actions-dropdown 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ref="linksrc=add_to_search_link" role="button" data-search-term=""Retina/anatomy and histology"[MAJR]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Retina/anatomy and histology"[MAJR]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link" aria-label="Toggle dropdown menu for keyword Retina / chemistry" tabindex="0" aria-controls="keyword-actions-mesh-terms-10" aria-expanded="false" data-pinger-ignore> Retina / chemistry </button><div id="keyword-actions-mesh-terms-10" class="keyword-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for keyword Retina / chemistry"><div class="title">Actions</div><div class="content"><ul class="keyword-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22Retina%2Fchemistry%22%5BMeSH%5D&sort=date&sort_order=desc" data-href="/?term=%22Retina%2Fchemistry%22%5BMeSH%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_keyword_link&mesh="Retina/chemistry"[MeSH]" data-ga-category="search" data-ga-action="mesh_term" data-ga-label="Retina / chemistry"> Search in PubMed </a></li><li><a class="search-in-mesh-link dropdown-block-link" ref="linksrc=search_in_mesh_link" href="https://www.ncbi.nlm.nih.gov/mesh?term=Retina" data-ga-category="search_mesh" data-ga-action="mesh_term_link" data-ga-label="Retina / chemistry"> Search in MeSH </a></li><li><a class="add-to-search-link dropdown-block-link" ref="linksrc=add_to_search_link" role="button" data-search-term=""Retina/chemistry"[MeSH]" data-ga-category="search" data-ga-action="add_to_search" data-ga-label=""Retina/chemistry"[MeSH]" href="#"> Add to Search </a></li></ul></div></div></div></li><li><div class="keyword-actions dropdown-block"><button class="keyword-actions-trigger trigger keyword-link major" aria-label="Toggle dropdown menu for keyword 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Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup - PubMed