Simply begin typing or use the editing tools above to add to
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modifications will be sent to our editors for review. ...also
may attempt to show where there are important differences among
the various groups. These goals often conflict. In a purely
genealogical system, each group must correspond to a single
lineage ( clade) composed of the common ancestor and all of its
descendants. A group that does not meet both of these
requirements is called a grade and may be used as an informal
group. Groups that do not... What made you want to look up
"clade"? Please share what surprised you most...