<s>
A	O
dendrogram	B-Application
is	O
a	O
diagram	O
representing	O
a	O
tree	O
.	O
</s>
<s>
in	O
hierarchical	B-Algorithm
clustering	I-Algorithm
,	O
it	O
illustrates	O
the	O
arrangement	O
of	O
the	O
clusters	O
produced	O
by	O
the	O
corresponding	O
analyses	O
.	O
</s>
<s>
in	O
computational	O
biology	O
,	O
it	O
shows	O
the	O
clustering	O
of	O
genes	O
or	O
samples	O
,	O
sometimes	O
in	O
the	O
margins	O
of	O
heatmaps	B-Application
.	O
</s>
<s>
In	O
this	O
case	O
,	O
the	O
dendrogram	B-Application
is	O
also	O
called	O
a	O
phylogenetic	O
tree	O
.	O
</s>
<s>
The	O
name	O
dendrogram	B-Application
derives	O
from	O
the	O
two	O
ancient	O
greek	O
words	O
(	O
)	O
,	O
meaning	O
"	O
tree	O
"	O
,	O
and	O
(	O
)	O
,	O
meaning	O
"	O
drawing	O
,	O
mathematical	O
figure	O
"	O
.	O
</s>
<s>
For	O
a	O
clustering	O
example	O
,	O
suppose	O
that	O
five	O
taxa	O
(	O
to	O
)	O
have	O
been	O
clustered	O
by	O
UPGMA	B-Algorithm
based	O
on	O
a	O
matrix	O
of	O
genetic	O
distances	O
.	O
</s>
<s>
The	O
hierarchical	B-Algorithm
clustering	I-Algorithm
dendrogram	B-Application
would	O
show	O
a	O
column	O
of	O
five	O
nodes	O
representing	O
the	O
initial	O
data	O
(	O
here	O
individual	O
taxa	O
)	O
,	O
and	O
the	O
remaining	O
nodes	O
represent	O
the	O
clusters	O
to	O
which	O
the	O
data	O
belong	O
,	O
with	O
the	O
arrows	O
representing	O
the	O
distance	O
(	O
dissimilarity	O
)	O
.	O
</s>
