DNA barcoding and phylogenetic relationships in Anatidae

Area of Science:

• Molecular Biology
• Genetics
• Ornithology
• Evolutionary Biology

Background:

• Mitochondrial cytochrome c oxidase subunit I (COI) is a widely recognized marker for phylogenetic studies.
• COI gene sequences are valuable for species identification and understanding evolutionary relationships in birds.

Purpose of the Study:

• To assess the efficacy of DNA barcoding using COI for species identification within the Anatidae family (ducks, geese, swans).
• To infer phylogenetic relationships among Anatidae genera using COI gene sequences.

Main Methods:

• DNA barcoding of the COI gene was performed on 79 Anatidae species across 26 genera.
• Kimura two-parameter (K2P) genetic distances were calculated to quantify sequence variation.
• Phylogenetic trees were constructed using the neighbor-joining method.

Main Results:

• DNA barcodes correctly identified 83.54% (66 out of 79) of the Anatidae species.
• Thirteen species exhibited shared COI barcode sequences with closely related congeners.
• Average genetic distance between species was significantly higher (41x) than within species, supporting species distinctiveness.
• Phylogenetic analysis revealed three main clades, with Dendrocygna and Nomonyx + Oxyura identified as basal lineages.
• The remaining taxa grouped into clades corresponding to the subfamilies Anserinae and Anatinae.

Conclusions:

• DNA barcoding of the COI gene is a robust and effective molecular tool for identifying species within the Anatidae family.
• The study provides valuable insights into the phylogenetic structure of Anatidae, confirming subfamily divisions and identifying early diverging lineages.
• COI barcoding facilitates accurate species-level identification and aids in resolving evolutionary relationships in waterfowl.