Figure 2.

Median-joining networks for each variable locus studied. Circles represent unique haplotypes, scaled by frequency and coloured by species (key inset). Each ‘tick’ represents one mutation, except between the Falkland Islands and continental clades in (a) and (b), which are separated by 12 and 11 mutations, respectively. Individuals are labelled by their DNA extraction number and source location (full specimen details in electronic supplementary material, table S1). (a,b) Mitochondrial haplotypes; (c,d) phased nuclear alleles. In some cases, the number of each allele observed is denoted by n. ARG, Argentina; CHL, Chile; FLK, Falkland Islands; s.d., steamer duck.