You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <alllinks galcontinue="Jennifer_Klug" />
  </query-continue>
  <query>
    <pages>
      <page ns="0" title="How to use this organic data science wiki" missing="" />
      <page pageid="110" ns="0" title="Cayelan Carey" />
      <page pageid="540" ns="0" title="Charlie White" />
      <page pageid="294" ns="0" title="Chris Duffy" />
      <page pageid="302" ns="0" title="Corinna Gries" />
      <page pageid="288" ns="0" title="Cycles" />
      <page pageid="381" ns="0" title="Directory of team members" />
      <page pageid="117" ns="0" title="General Lake Model" />
      <page pageid="118" ns="0" title="Hedonic Model" />
      <page pageid="534" ns="0" title="Hilary Dugan" />
    </pages>
  </query>
</api>