caret"></span>
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  <ul class="dropdown-menu" role="menu">
    <li>
      <a href="../articles/index.html">Overview</a>
    </li>
    <li>
      <a href="../articles/wolves_ex.html">Ex 1: Wolves</a>
    </li>
    <li>
      <a href="../articles/geese_ex.html">Ex 2: Geese</a>
    </li>
    <li>
      <a href="../articles/lake_ex.html">Ex 3: Lake</a>
    </li>
    <li>
      <a href="../articles/killerwhale_ex.html">Ex 4: Killer whale</a>
    </li>
    <li>
      <a href="../articles/isopod_ex.html">Ex 5: