1 #ISTC20 #Sesh9 The Sand Plover complex has long been a source of debate among taxonomists. This group is currently considered to be two species, each with numerous subspecies, but has never been investigated genetically. #ornithology #shorebirds #waders

2 #ISTC20 #Sesh9 Using biometrics, Greater Sand Plover is clearly separable from Lesser. However, based on breeding plumage & breeding range, Lesser can be further split into two groups: 'atrifrons' & 'mongolus'. It has been suggested that these two may be incipient species.

3 #ISTC20 #Sesh9 For this study samples were taken from the wintering/staging sites of Bar Al Hickman, Oman & Mai Po Marshes, Hong Kong. These were then supplemented with sequences from Genbank. We analysed 5 mitochondrial & 6 nuclear loci to create a robust phylogeny. #genetics

4 #ISTC20 #Sesh9 A BEAST* phylogeny based on all 11 genes confidently places the ‘atrifrons’ group as sister to Greater, with ‘mongolus’ group having diverged earlier. Sand plovers are therefore paraphyletic, and as such, the current 2 species taxonomy requires revision.

5 #ISTC20 #Sesh9 Mitochondrial & Z-linked genes were fixed for all groups, indicating high levels of philopatry across all taxa. However autosomal genes showed admixture between groups. This may be due to retention of ancestral alleles or low levels of ongoing gene flow.

6 #ISTC20 #Sesh9 Based on this new genetic evidence, in addition to differences in biometrics, plumage characters and allopatric breeding ranges, we argue that the Sand Plover complex is comprised of 3 species: C. leschenaultii, C. mongolus and C. atrifrons. #taxonomy