Download Monophyly – the property of an inclusive group of organisms of

Monophyly – the property of an
inclusive group of organisms of
shared common ancestry
Polyphyly – the property of being
unrelated by descent
Paraphyly – the property of a group
of organisms of shared common
ancestry that does not include all of
the evolutionary derivatives of that
common ancestor
a
b
c
d
e
a
b
c
d
e
a
b
c
d
e
a
b
c
d
e
Monophyletic groups are the only ones
intended to be classified taxonomically
Paraphyletic groups are undesirable
in classification because those
organisms most closely related
(i.e., a and b) are not grouped together
a
b
c
-most likely to have been based on superficially
conspicuous traits, therefore many examples discovered
with the application of molecular data to large samples
d
e
“Apes” are a paraphyly group
guenons
gibbons
orang
gorilla
chimps
human
Neotropical toucans
Ramphastidae
Neotropical barbets
Capitonidae
African barbets
Lybiidae
Asian barbets
Megalaimidae
There are plenty of examples of paraphyletic groups among birds
e.g., “barbets”
Lineage Sorting - the
process by which ancestral
polymorphism is lost by
drift and paraphyletic
gene lineages become
monophyletic
incomplete
complete
From Futuyma 1998 Evolutionary Biology
Distinct evolutionary histories of species and their genes
Ebersberger et al. Mol Biol Evol 2007;24:2266-2276
Ebersberger et al. Mol Biol Evol 2007;24:2266-2276