1.0MCQhttps://imagesdanslapierre.mcq.org/en/Jean Tanguayhttps://imagesdanslapierre.mcq.org/en/author/jeantanguay/rich600338<blockquote class="wp-embedded-content" data-secret="YMGruNJLGS"><a href="https://imagesdanslapierre.mcq.org/en/discover/when/">When</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://imagesdanslapierre.mcq.org/en/discover/when/embed/#?secret=YMGruNJLGS" width="600" height="338" title="“When” — MCQ" data-secret="YMGruNJLGS" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript"> /* <![CDATA[ */ /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://imagesdanslapierre.mcq.org/wp-includes/js/wp-embed.min.js /* ]]> */ </script> How long ago were the oldest rock art sites created in Canada? A range of dating methods have been applied to rock art sites over the years, but research efforts have yielded more or less reliable results. However, it can be said that this “artistic” means of expression existed at least 5,000 years ago and has continued over millennia.https://imagesdanslapierre.mcq.org/wp-content/uploads/2019/01/quand.jpg