jquery:
$('div.animalcontent').hide();
$('div').hide();
$('p.animal').bind('mouseover', function() {
$('div.animalcontent').fadeOut();
$('#'+$(this).attr('id')+'content').fadeIn();
});
html:
<p class='animal' id='dog'>dog url</p><div id='dogcontent' class='animalcontent'>Doggiecontent!</div>
<p class='animal' id='cat'>cat url</p><div id='catcontent' class='animalcontent'>Pussiecontent!</div>
<p class='animal' id='snake'>snake url</p><div id='snakecontent'class='animalcontent'>Snakecontent!</div>
-edit-
yeah sure, here you go -- JSFiddle