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HTML

<h1>Taxonomy and systematics</h1>

<p>
    The Andean Condor was described by Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae and retains its original binomial name of Vultur gryphus.[2] The Andean Condor is sometimes called the Argentinean Condor, Bolivian Condor, Chilean Condor, Colombian Condor, Ecuadorian Condor, or Peruvian Condor after one of the nations to which it is native. The generic term Vultur is directly taken from the Latin vultur or voltur, which means "vulture".[3] Its specific epithet is derived from a variant of the Greek word γρυπός (grupós, "hook-nosed").[4] The word condor itself is derived from the Quechua kuntur.[5][6]
</p>
<p>
    The exact taxonomic placement of the Andean Condor and the remaining six species of New World Vultures remains unclear.[7] Though both are similar in appearance and have similar ecological roles, the New World and Old World Vultures evolved from different ancestors in different parts of the world and are not closely related. Just how different the two families are is currently under debate, with some earlier authorities suggesting that the New World vultures are more closely related to storks.[8] More recent authorities maintain their overall position in the order Falconiformes along with the Old World Vultures[9] or place them in their own order, Cathartiformes.[10] The South American Classification Committee has removed the New World Vultures from Ciconiiformes and instead described them as incertae sedis, but notes that a move to Falconiformes or Cathartiformes is possible.[7]
    
    The Andean Condor is the only accepted living species of its genus, Vultur.[11] Unlike the California Condor, which is known from extensive fossil remains and some additional ones of congeners, the fossil record of the Andean Condor recovered to date is scant. Presumed Plio-/Pleistocene species of South American condors were later recognized to be not different from the present species, although one known only...

CSS

p {
    margin: 10px;
}

#posText {
    background: red;
}

.clone {
    border: 1px solid red;
    background: blue;
    position: absolute
}

JavaScript

var getTextOffset = new Class({
    Implements: [Options],
    options: {
        selector: "*", // all elements
        filter: "innerHTML", // only those that have this property are worth lookign at
        skip: ["link", "style", "script","head","html","meta","input","textarea","select","body"] // useless tags we don't care about
    },
    initialize: function(text, options) {
        this.setOptions(options);
        if (!text) return; // nothing to do.
        
        this.elements = document.getElements(this.options.selector).filter(function(el) {
            return this.options.filter in el && !this.options.skip.contains(el.get("tag"));
        }, this);
        
        if (!this.elements.length)
            return;
        
        return this.findText(text);
    },
    findText: function(text) {
        var coords = false;
        this.elements.some(function(el) {
            var eltext = el.get("html");
            if (eltext.contains(text)) {
                var c = el.getCoordinates();
                var clone = new Element("div", {
                    "class": "clone",
                    styles: c,
                    html: eltext.replace(text, "<span id='posText'>"+text+"</span>")
                }).inject(document.body, "top").fade(0,.5);
                coords = document.id("posText").getCoordinates();
                clone.destroy();
            }
        });
        
        return coords;
    }
});


var pleistoscene = new getTextOffset("Pleistocene");

if (pleistoscene) // found text so highlight it
new Element("div", {
    styles: $merge(pleistoscene, {
        position: "absolute",
        background: "yellow"
    }),
    opacity: .7,
    title: pleistoscene.top + "px top"
}).inject(document.body); // mouseover the yelow element to see offset (pleitoscene.top)