Data from: Death is on our side: paleontological data drastically modify phylogenetic hypotheses

Fossils are the only remaining evidence of the majority of species that
have ever existed, providing a direct window into events in evolutionary
history that shaped the diversification of life on Earth. Phylogenies
underpin our ability to make sense of evolution but are routinely inferred
using only data available from living organisms. Although extinct taxa
have been shown to add crucial information for inferring macroevolutionary
patterns and processes (such as ancestral states, paleobiogeography and
diversification dynamics), the role fossils play in reconstructing
phylogeny is controversial. Since the early years of phylogenetic
systematics, different studies have dismissed the impact of fossils due to
their incompleteness, championed their ability to overturn phylogenetic
hypotheses or concluded that their behavior is indistinguishable from that
of extant taxa. Based on taxon addition experiments on empirical data
matrices, we show that the inclusion of paleontological data has a
remarkable effect in phylogenetic inference. Fossils often have higher
levels of topological influence than extant taxa, while inducing unique
topological rearrangements. Previous studies have proposed a suite of
explanations for the topological behavior of fossils, such as their
retention of unique morphologies or their ability to break long branches.
We develop predictive models that demonstrate that the possession of
distinctive character state combinations is the primary predictor of the
degree of induced topological change, and that the relative impact of taxa
(fossil and extant) can be predicted to some extent before any
phylogenetic analysis. Our results bolster the consensus of recent
empirical studies by showing the unique role of paleontological data in
phylogenetic inference, and provide the first quantitative assessment of
its determinants, with broad consequences for the design of taxon sampling
in both morphological and total-evidence analyses.