Abstract
Morphological integration predicts that correlated characters will coevolve; thus, each distinct suite of correlated characters might be expected to evolve according to a separate clock or 'pacemaker'. Characters in a large morphological dataset for mammals were found to be evolving according to seven separate clocks, each distinct from the molecular clock. Total-evidence tip-dating using these multiple clocks inflated divergence time estimates, but potentially improved topological inference. In particular, single-clock analyses placed several meridiungulates and condylarths in a heterodox position as stem placentals, but multi-clock analyses retrieved a more plausible and orthodox position within crown placentals. Several shortcomings (including uneven character sampling) currently impact upon the accuracy of total-evidence dating, but this study suggests that when sufficiently large and appropriately constructed phenotypic datasets become more commonplace, multi-clock approaches are feasible and can affect both divergence dates and phylogenetic relationships.
Original language | English |
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Article number | 20160033 |
Number of pages | 5 |
Journal | Biology Letters |
Volume | 12 |
Issue number | 7 |
DOIs | |
Publication status | Published - 1 Jul 2016 |
Keywords
- Bayesian phylogenetics
- Mammalia
- Morphological integration
- Relaxed clocks
- Tip-dating
- Total-evidence dating