INVESTIGADORES
DONATO Mariano Humberto
artículos
Título:
Parsimony analysis of endemicity describes but does not explain: an illustrated critique
Autor/es:
GARZÓN-ORDUÑA, IVONNE J.; MIRANDA- ESQUIVEL, DANIEL RAFAEL; DONATO, MARIANO
Revista:
JOURNAL OF BIOGEOGRAPHY
Referencias:
Año: 2008 vol. 35 p. 903 - 913
ISSN:
0305-0270
Resumen:
Aim To demonstrate that parsimony analysis of endemicity (PAE) is not
analogous to a cladistic biogeographical analysis.
analogous to a cladistic biogeographical analysis.
To demonstrate that parsimony analysis of endemicity (PAE) is not
analogous to a cladistic biogeographical analysis.
Location We used six data sets from previously published studies from around
the world.
the world.
We used six data sets from previously published studies from around
the world.
Methods In order to test the efficiency of PAE in recovering historical
relationships among areas, we performed an empirical comparison of nodes
recovered with PAE, primary Brooks parsimony analysis (BPA), and an eventbased
method using three models (maximum codivergence, reconciled trees, and
the default model of the treefitter program) for six data sets. We measured the
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
relationships among areas, we performed an empirical comparison of nodes
recovered with PAE, primary Brooks parsimony analysis (BPA), and an eventbased
method using three models (maximum codivergence, reconciled trees, and
the default model of the treefitter program) for six data sets. We measured the
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
In order to test the efficiency of PAE in recovering historical
relationships among areas, we performed an empirical comparison of nodes
recovered with PAE, primary Brooks parsimony analysis (BPA), and an eventbased
method using three models (maximum codivergence, reconciled trees, and
the default model of the treefitter program) for six data sets. We measured the
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
treefitter program) for six data sets. We measured the
performance of PAE in recovering historical area relationships by counting the
number and examining the content of nodes recovered by PAE and by historical
methods. The dispersal/vicariance ratio was calculated to assess the prevalence
of dispersal or vicariance in each reconstruction and its relationship to the
performance of PAE.
Results Our results show that PAE recovers an average of 17.25% of historical
nodes. PAE and BPA tend to provide similar results; however, in relation to the
event-based models, PAE performance was poor under all the tested scenarios.
Although in some cases PAE reconstructions are more resolved than historical
reconstructions, this does not necessarily mean that PAE produces more
informative answers. These additional nodes correspond to unsupported
statements that are based solely on the distributional data of taxa and not on
their phylogenetic history. In other words, these nodes were not found by the
historical methods, which take phylogenetics into account. The number of
historical nodes recovered using PAE was in general negatively correlated with the
dispersal/vicariance ratio.
nodes. PAE and BPA tend to provide similar results; however, in relation to the
event-based models, PAE performance was poor under all the tested scenarios.
Although in some cases PAE reconstructions are more resolved than historical
reconstructions, this does not necessarily mean that PAE produces more
informative answers. These additional nodes correspond to unsupported
statements that are based solely on the distributional data of taxa and not on
their phylogenetic history. In other words, these nodes were not found by the
historical methods, which take phylogenetics into account. The number of
historical nodes recovered using PAE was in general negatively correlated with the
dispersal/vicariance ratio.
Our results show that PAE recovers an average of 17.25% of historical
nodes. PAE and BPA tend to provide similar results; however, in relation to the
event-based models, PAE performance was poor under all the tested scenarios.
Although in some cases PAE reconstructions are more resolved than historical
reconstructions, this does not necessarily mean that PAE produces more
informative answers. These additional nodes correspond to unsupported
statements that are based solely on the distributional data of taxa and not on
their phylogenetic history. In other words, these nodes were not found by the
historical methods, which take phylogenetics into account. The number of
historical nodes recovered using PAE was in general negatively correlated with the
dispersal/vicariance ratio.
Main conclusions Our results show that PAE is unable to recover historical
patterns and therefore does not fit into the current paradigm of historical
biogeography. These findings raise doubts regarding conclusions derived from
biogeographical studies that interpret PAE trees as area cladograms. We
acknowledge that PAE aims to describe but does not explain the current
distribution of organisms. It is therefore a useful tool in other biogeographical or
ecological analyses for exploring the distribution of taxa or for establishing
hypotheses of primary homology between areas.
patterns and therefore does not fit into the current paradigm of historical
biogeography. These findings raise doubts regarding conclusions derived from
biogeographical studies that interpret PAE trees as area cladograms. We
acknowledge that PAE aims to describe but does not explain the current
distribution of organisms. It is therefore a useful tool in other biogeographical or
ecological analyses for exploring the distribution of taxa or for establishing
hypotheses of primary homology between areas.
Our results show that PAE is unable to recover historical
patterns and therefore does not fit into the current paradigm of historical
biogeography. These findings raise doubts regarding conclusions derived from
biogeographical studies that interpret PAE trees as area cladograms. We
acknowledge that PAE aims to describe but does not explain the current
distribution of organisms. It is therefore a useful tool in other biogeographical or
ecological analyses for exploring the distribution of taxa or for establishing
hypotheses of primary homology between areas.