Fossils improve phylogenetic analyses of morphological characters

Area of Science:

• Paleontology
• Evolutionary Biology
• Phylogenetics

Background:

• Fossils offer direct evidence of past life and evolutionary events.
• Their integration into phylogenetic analyses can calibrate divergence times and reveal macroevolutionary dynamics.
• The impact of fossils on morphological phylogenetic reconstruction and the utility of tip-dated inference remain debated.

Purpose of the Study:

• To evaluate the performance of phylogenetic inference methods with varying fossil sampling and missing data.
• To assess the consequences of explicitly incorporating fossil stratigraphic ages using tip-dated inference.
• To determine how fossils affect phylogenetic accuracy and node resolution in morphological datasets.

Main Methods:

• Simulations were used to test phylogenetic inference methods.
• Analyses compared the performance of methods with and without fossil data.
• Tip-dated inference under the fossilized birth-death process was evaluated against undated methods.

Main Results:

• Fossil taxa enhance phylogenetic analysis of morphological data, improving accuracy and increasing resolved nodes, even when fragmentary.
• Fossils help resolve uncertain ancient relationships that are often incorrectly inferred from extant taxa alone.
• Tip-dated analyses incorporating fossil stratigraphic ages outperform undated methods, highlighting the value of temporal information.

Conclusions:

• Fossils are essential for accurate phylogenetic reconstruction, providing unique morphological and temporal signals.
• Incorporating fossils, especially using tip-dated inference, is necessary for a faithful understanding of evolutionary history.
• Fossil data improve phylogenetic accuracy and help to resolve complex evolutionary relationships.