10.5061/DRYAD.M010P
Hunt, Gene
Smithsonian Institution
Hopkins, Melanie J.
American Museum of Natural History
Lidgard, Scott
Field Museum of Natural History
Data from: Simple versus complex models of trait evolution and stasis as a
response to environmental change
Dryad
dataset
2015
gradualism
punctuated equilibrium
2015-10-07T00:00:00Z
2015-10-07T00:00:00Z
en
https://doi.org/10.1073/pnas.1403662111
810147 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Previous analyses of evolutionary patterns, or modes, in fossil lineages
have focused overwhelmingly on three simple models: stasis, random walks,
and directional evolution. Here we use likelihood methods to fit an
expanded set of evolutionary models to a large compilation of
ancestor–descendant series of populations from the fossil record. In
addition to the standard three models, we assess more complex models with
punctuations and shifts from one evolutionary mode to another. As in
previous studies, we find that stasis is common in the fossil record, as
is a strict version of stasis that entails no real evolutionary changes.
Incidence of directional evolution is relatively low (13%), but higher
than in previous studies because our analytical approach can more
sensitively detect noisy trends. Complex evolutionary models are often
favored, overwhelmingly so for sequences comprising many samples. This
finding is consistent with evolutionary dynamics that are, in reality,
more complex than any of the models we consider. Furthermore, the timing
of shifts in evolutionary dynamics varies among traits measured from the
same series. Finally, we use our empirical collection of evolutionary
sequences and a long and highly resolved proxy for global climate to
inform simulations in which traits adaptively track temperature changes
over time. When realistically calibrated, we find that this simple model
can reproduce important aspects of our paleontological results. We
conclude that observed paleontological patterns, including the prevalence
of stasis, need not be inconsistent with adaptive evolution, even in the
face of unstable physical environments.
paleoTS files - zip archiveThis zip archive holds 771 plain text files in
paleoTS format. Each stores the raw data for a trait time-series, with
columns for trait sample sizes, trait means, trait variances, and sample
ages.paleoTS files.zippaleoTS data - RData formatSame data as
'paleoTS files.zip', but all combined into a single file
readable by R. Double-clinking this file will open R and make available in
the R Workspace an object called 'tsList' which is a list of the
771 time-series (paleoTS) objects.paleoTS files.RDatapaleoTS summary -
XLSX formatExcel spreadsheet with auxiliary data for these files,
including the number of samples, environmental context, and taxonomic
group of the fossils. Includes also reference information for the
published papers from which these data were drawn.paleoTS
summary.xlsxpaleoTS summary - CSV formatSame as paleoTS
'summary.xlsx' but in Comma-separated-value format.paleoTS
summary.csvpaleoTS referencesSame as information in second worksheet of
"paleoTS summary.xlsx", here separated out as CSV format.