DOI: 10.5061/dryad.hm55b
title: Data from: Evolutionarily distinct “living fossils” require both lower speciation and lower extinction rates

description: As a label for a distinct category of life, ‘living fossil’ is
 controversial. The term has multiple definitions and it is unclear whether
 the label can be genuinely used to delimit biodiversity. Even taking a
 purely phylogenetic perspective where a proxy for the living fossil is
 evolutionary distinctness (ED), an inconsistency arises: does it refer to
 “dead-end” lineages doomed to extinction or “panchronic” lineages that
 survive through multiple epochs? Recent tree-growth model studies indicate
 that speciation rates must have been unequally distributed between species
 in the past to produce the shape of the tree of life. Although an uneven
 distribution of speciation rates may create the possibility for a distinct
 group of living fossil lineages, such a grouping could only be considered
 genuine if extinction rates also show a consistent pattern, be it
 indicative of dead-end or panchronic lineages. To determine whether
 extinction rates also show an unequal distribution, we developed a
 tree-growth model where the probability of speciation and extinction is a
 function of a tip’s ED. We simulated 1,000s of trees where the ED function
 for a tip is randomly and independently determined for speciation and
 extinction rates. We find that simulations where the most evolutionarily
 distinct tips have lower rates of speciation and extinction produce
 phylogenetic trees closest in shape to empirical trees. This implies that
 a distinct set of lineages with reduced rates of diversification,
 indicative of a panchronic definition, is required to create the shape of
 the tree of life.
description: Supplementary
 informationFigures S1-S15 // Tables
 S1-S2SupportingInformation.pdfData and results 1Part 1. tar.gz compressed folder containing: initial tree data for running R pipeline (data/) and a results folder for every analysis run (results/). References for phylogenetic trees can be found in metadata.csv. For more details, see: https://github.com/DomBennett/Project-EDBMMxaaData and results 2Part 2. tar.gz compressed folder containing: initial tree data for running R pipeline (data/) and a results folder for every analysis run (results/). References for phylogenetic trees can be found in metadata.csv. For more details, see: https://github.com/DomBennett/Project-EDBMMxabData and results 3Part 3. tar.gz compressed folder containing: initial tree data for running R pipeline (data/) and a results folder for every analysis run (results/). References for phylogenetic trees can be found in metadata.csv. For more details, see: https://github.com/DomBennett/Project-EDBMMxacData and results 4Part 4. tar.gz compressed folder containing: initial tree data for running R pipeline (data/) and a results folder for every analysis run (results/). References for phylogenetic trees can be found in metadata.csv. For more details, see: https://github.com/DomBennett/Project-EDBMMxadData and results 5Part 5. tar.gz compressed folder containing: initial tree data for running R pipeline (data/) and a results folder for every analysis run (results/). References for phylogenetic trees can be found in metadata.csv. For more details, see: https://github.com/DomBennett/Project-EDBMMxae