� may refer to species, populations, individuals, or sequences within an individual.</span> each 
 are defined.<span style="display: none;">RH_Groups_of_taxa</span>&#160;&#160;The 
 net average distance between two groups is given by</p>
<p style="font-size: 12pt;"><i>d</i><sub>A</sub> = <i>d</i><sub>XY</sub> 
 – (<i>d</i><sub>X</sub> + <i>d</i><sub>Y</sub>)/2</p>
<p style="font-size: 12pt;">where, <i>d</i><sub>XY</sub> is the average 
 distance between groups X and Y, and <i>d</i><sub>X</sub> and <i>d</i