pan> <span class="fl">50</span>, end <span class="op">=</span> <span class="fl">150</span>, snapshots <span class="op">=</span> <span class="fl">3</span><span class="op">)</span></span></span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="co"># we can check the positions of all populations interactively by plotting their</span></span></span>
<span class="r-in"><span><span class="co"># ranges together on a single map</span></span></span>
<span class="r-in"><span><span class="f