Late Eocene Epoch | geochronology

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Ca. 1500." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-famous-artworks-by-leonardo-da-vinci" >10 Famous Artworks by Leonardo da Vinci</a> </div> </div> </div> </div> </div> </div> <button class="drawerToggle btn position-sticky border btn-xs btn-white btn-circle rounded-sm d-none d-lg-flex " type="button" aria-label="Toggle Drawer"> <em class="material-icons font-18 text-blue" data-icon="keyboard_arrow_left"></em> </button> </div> </div> <div class="col"> <div class="h-100 ml-0 pr-lg-0"> <div class="h-100 grid gx-0 gx-lg-20"> <div class="h-100 col-sm d-flex flex-column"> <div class="toc-sticky-header d-none d-lg-none bg-gray-50 px-10 px-sm-30 position-sticky w-100 "> <div class="toc-sticky-header-inner-container align-items-center d-flex mx-auto h-100 w-100"> <button class="d-flex d-lg-none btn btn-sm btn-white text-blue border-2 border-gray-100 gtm-mobile-toc-header-button js-sections-button d-lg-none p-10"> <em class="material-icons my-n5 md-icon" data-icon="toc"></em> Contents </button> <div class="header-ai-ask-button-placeholder"></div> <div class="header-ai-summarize-button-placeholder"></div> </div> </div> <div class="grey-box w-100 grey-box-middle"> <div class="grey-box-content mx-auto w-100"> <br class="d-block mt-20"> <div class="topic-header"> <div class="d-flex align-items-top justify-content-between"> <div class="d-flex flex-column"> <div> <div> <h1>late Eocene Epoch</h1></div> </div> <div class="topic-identifier font-16 font-md-20">geochronology</div> </div> </div> <div class="d-none d-sm-flex flex-row"> </div> <div class="toc-header-marker"></div> <button class="ai-ask-button btn border-2 js-header-ai-ask-button d-none btn-sm btn-outline-red-400 border-red-400 mr-0 mr-lg-10 ml-5 ml-sm-10 ml-lg-0 p-10"> Ask the Chatbot a Question </button> </div> <div id="ref1"><article><span class="marker before-article"></span><section data-level="1"></section></article><section class="index-entries"><h2 class="h3"><strong>Learn about this topic</strong> in these articles:</h2><section><h3>appearance of porcupine-like rodents</h3><ul class="list-unstyled"><li><div class="md-assembly-wrapper card-media " data-type="image"><img src="https://cdn.britannica.com/36/145636-050-586F0C8E/groups-outbreaks-plague-grasshopper-mouse-prairie-dogs.jpg?w=300" alt="black-tailed prairie dog" data-width="1600" data-height="1155" loading="lazy"></div> <span class="index-xref">In <a href="https://www.britannica.com/animal/rodent/Evolution-and-classification#ref756186" class="md-crosslink " data-show-preview="true">rodent: Evolution and classification</a></span><p class="topic-paragraph">Late Eocene to present. Family Echimyidae (American spiny rats) 71 species in 17 genera, 21 extinct genera. Late Oligocene to present in South America, Pleistocene to present in West Indies. Family Octodontidae (rock rats, degus, viscachas, viscacha </p><a class="read-more" href="/animal/rodent/Evolution-and-classification#ref756186">Read More</a></li></ul></section><section><h3>Eocene Epoch</h3><ul class="list-unstyled"><li><div class="md-assembly-wrapper card-media " data-type="image"><img src="https://cdn.britannica.com/65/12665-004-5CACDC60/Coryphodon-mammals-deposits-Late-Paleocene-Early-Eocene-1898.jpg?w=300" alt="Coryphodon, a genus of primitive hoofed mammals known from Late Paleocene and Early Eocene deposits. Restoration painting by Charles R. Knight, 1898." data-width="380" data-height="300" loading="lazy"></div> <span class="index-xref">In <a href="https://www.britannica.com/science/Eocene-Epoch#ref44393" class="md-crosslink " data-show-preview="true">Eocene Epoch</a></span><p class="topic-paragraph">…38 million years ago), and Late (38 million to 33.9 million years ago) epochs. The name Eocene is derived from the Greek <em>eos</em>, for “dawn,” referring to the appearance and diversification of many modern groups of organisms, especially mammals and mollusks. </p><a class="read-more" href="/science/Eocene-Epoch#ref44393">Read More</a></li></ul></section></section></div> </div> </div> </div> <aside class="col-md-da-320" data-page="1"></aside> </div> </div> </div> </div> </article></div> </div></div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"INDEX","pageNumber":1,"pagesTotal":1,"pageId":331300,"pageLength":0,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/libs/jquery-3.5.0.min.js?v=3.130.14"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-130/dist/topic-page.js?v=3.130.14' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"INDEX","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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Late Eocene Epoch | geochronology | Britannica