Forest giants on different evolutionary branches: Ecomorphological convergence in helicopter damselflies

Area of Science:

• Evolutionary Biology
• Insect Systematics
• Phylogenetics

Background:

• Convergent evolution leads to analogous traits independently across diverse lineages.
• Giant damselflies (Afrotropical and Neotropical) exhibit striking ecological and morphological similarities.
• Previous phylogenetic studies have yielded conflicting hypotheses regarding their evolutionary relationships.

Purpose of the Study:

• To investigate the evolutionary history and phylogenetic placement of Afrotropical and Neotropical giant damselflies.
• To test the hypothesis of monophyly between these geographically distinct giant damselfly lineages.
• To determine the timing of divergence and explore potential vicariance events.

Main Methods:

• Molecular phylogenetic analysis using a comprehensive supermatrix.
• Inclusion of a wide range of outgroup taxa for robust phylogenetic inference.
• Molecular divergence time estimation to reconstruct evolutionary timelines.

Main Results:

• The molecular data strongly reject the monophyly of Afrotropical and Neotropical giant damselflies.
• Phylogenetic analyses contradict previous morphological and molecular inferences supporting monophyly.
• Divergence time estimates place the origin of Afrotropical lineages in the late Paleogene and Neotropical lineages at the Cretaceous/Paleogene boundary.

Conclusions:

• The observed similarities in giant damselflies are a product of independent convergent evolution, not shared ancestry.
• This finding refutes the long-standing West Gondwana vicariance hypothesis for these insects.
• The study highlights an astonishing case of Amphi-Atlantic tropical convergent evolution driven by environmental factors.