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| Ecologists and biogeographers usually rely on a single phylogenetic tree to study evolutionary processes that affectmacroecological
patterns. This approach ignores the fact that each phylogenetic tree is a hypothesis about the evolutionary history of a clade, and
cannot be directly observed in nature. Also, trees often leave out many extant species, or include missing species as polytomies
because of a lack of information on the relationship among taxa. Still, researchers usually do not quantify the effects of phylogenetic
uncertainty in ecological analyses. We propose here a novel analytical strategy to maximize the use of incomplete phylogenetic
information, while simultaneously accounting for several sources of phylogenetic uncertainty that may distort statistical inferences
about evolutionary processes. We illustrate the approach using a clade-wide analysis of the hummingbirds, evaluating how
different sources of uncertainty affect several phylogenetic comparative analyses of trait evolution and biogeographic patterns.
Although no statistical approximation can fully substitute for a complete and robust phylogeny, the method we describe and
illustrate enables researchers to broaden the number of clades for which studies informed by evolutionary relationships are
possible, while allowing the estimation and control of statistical error that arises from phylogenetic uncertainty. Software tools to
carry out the necessary computations are offered. | |
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