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Updated: Jan 21, 2026
09:33
A Technical Perspective in Modern Tree-ring Research - How to Overcome Dendroecological and Wood Anatomical Challenges
Published on: March 5, 2015
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Excavating ghost footprints and tangled trees from modern genomes.
Arne Jacobs1, Nina Overgaard Therkildsen1
1Department of Natural Resources, Cornell University, Ithaca, NY, USA.
Molecular Ecology
|August 6, 2019
Summary
Killer whales show complex evolutionary histories due to gene flow and admixture. Researchers uncovered ancient admixture with an extinct lineage, revealing new insights into their demographic past.
Area of Science:
- Evolutionary biology
- Population genetics
- Genomics
Background:
- Bifurcating trees are insufficient for species with gene flow and admixture.
- Genomic data resolution and sample distribution limit evolutionary insights.
- Killer whale (Orcinus orca) evolutionary history is complex.
Discussion:
- Foote et al. used novel analytical methods from human genetics.
- Recurrent vicariance and admixture patterns were identified in killer whales.
- Ancient admixture with an extinct lineage was detected.
Key Insights:
- Clear signatures of ancient admixture with a now extinct "ghost" lineage were found.
- This is one of the first accounts of archaic introgression in a nonhominid species.
- The study highlights complex evolutionary dynamics in killer whales.
Outlook:
- The study provides a roadmap for inferring evolutionary history in nonmodel species.
- Cost-effective sequencing and novel analytical approaches are key.
- This work promises advancements in understanding species' demographic histories.
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