Allopatric speciation can result from elevational topography. Climatic changes can drive species into altitudinal zones, isolating populations.
<p><b>1:</b> Higher elevation peaks act as "islands" to promote speciation.
</p>
<b>2:</b> Lower elevation valleys act as "islands" to promote speciation.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1">[1]</a></sup>
<a href="//commons.wikimedia.org/wiki/User:Azcolvin429" title="User:Azcolvin429">Andrew Z. Colvin</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>