ce/group_by.html" class="external-link">group_by</a></span><span class="op">(</span><span class="va">species</span><span class="op">)</span> <span class="op"><a href="pipe.html">%&gt;%</a></span> </span></span>
<span class="r-in"><span>  <span class="fu"><a href="https://dplyr.tidyverse.org/reference/summarise.html" class="external-link">summarise</a></span><span class="op">(</span>body_mass_g <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/mean.html" class="external-link">mean</a