Figure 4: Heat-map of swIAV migration between locations.

Countries are listed in order of increasing geographical distance from Argentina (ARG). MEX=Mexico, USA=the United States, CAN=Canada, EUR=Europe, JPN=Japan, CHN=China (including Hong Kong SAR and Taiwan), KOR=South Korea, THA=Thailand, VNM=Vietnam. The intensity of the colour (red=high; white=low) reflects the number (no.) of ‘Markov jump’ counts inferred over the totality of phylogenies (all segments, all lineages) from one location to another (asymmetrical). Markov jump counts measure the number of inferred location state transitions, modelled by a continuous-time Markov chain process, that occur along the branches of the phylogeny. For clarity the heat-map has been divided into four sections representing (a) viral migration events within the Americas and between the Americas and Europe; (b) migrations from the Americas/Europe to Asia; (c) migrations from Asia to the Americas/Europe; and (d) migrations between the Asian countries.