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Updated: Jun 23, 2026
08:07
Environmental DNA Sampling from Whale-Watching Vessels for Cetacean Monitoring
Published on: April 10, 2026
Convergent Functional Genomic Evolution Underlying Repeated Freshwater Colonization in Cetaceans
D Pinilla-Beltrán1, Leonardo Duarte-Santos1, Mariana F Nery2
1Laboratory of Evolutionary Genomics, Department of Genetics, Evolution, Immunology and Microbiology, University of Campinas, Cidade Universitária, Campinas, Sao Paulo, 13083-862, Brazil.
Journal of Molecular Evolution
|June 22, 2026
Summary
Riverine cetaceans evolved unique adaptations for freshwater life. Genomic analysis reveals convergent evolution in immune, metabolic, and developmental pathways, highlighting key molecular changes enabling this remarkable transition.
Area of Science:
- Evolutionary biology
- Genomics
- Mammalian adaptation
Background:
- Cetacean transition from marine to freshwater environments is a significant evolutionary event.
- Genomic basis of freshwater adaptation in cetaceans is not well understood.
Purpose of the Study:
- Investigate genomic signatures of freshwater adaptation in riverine cetaceans.
- Identify key molecular adaptations and evolutionary mechanisms enabling freshwater colonization.
Main Methods:
- Comparative evolutionary analyses of six riverine cetacean species.
- Positive selection analysis, gene family dynamics (CAFE), and evolutionary rate convergence (RERconverge).
Main Results:
- Identified positive selection in NSMAF and CTRL genes related to inflammation and digestion.
- Detected adaptive signatures in hematopoiesis, osmoregulation, skeletal development, and immune responses.
- Found convergent evolution in 95 genes related to cellular nitrogen compound responses and transcriptional regulation.
Conclusions:
- Freshwater adaptation in cetaceans involves convergent evolution across fundamental biological systems.
- Molecular mechanisms include immune responses, metabolic regulation, and morphological development.
- Provides insights into speciation and successful colonization of freshwater ecosystems by cetaceans.
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