"Supporting Information Table S1 Results of model fitting for the 39 alternative models of divergence for pool-seq data. Models are ranked by model category. SI, strict isolation; IM, isolation-with-migration; AM, ancient migration with one contact period; PAM, ancient migration with two periods of contact; SC, secondary contact with one period of contact; PSC, the same model with two periods of contact. Models involving strict isolation were implemented with no recent expansion, recent expansion (ex), heterogeneity of effective population size across the genome (2N) and both heterogeneity of effective population size across the genome and recent expansion (2Nex). All models of divergence-with-gene-flow were implemented with recent expansion (ex), heterogeneity of migration rate across the genome (2M2P), heterogeneity of migration rate across the genome and recent expansion (2M2Pex) and and heterogeneity in both migration rate and population size (2N2M2P)." Model k LogL AIC Model description Model comparison within Model comparison between SI 4 -2421.226 4850.451 Strict isolation IM 6 -2383.521 4779.041 Isolation-with-migration SI*** AM 7 -2362.277 4738.554 Ancient migration "SI***, IM***, SC+++, PSC+++" SC 7 -2382.615 4779.230 Secondary contact "SI***, IMNS, PSC-1.81" PAM 7 -2360.540 4735.080 Ancient migration with two phases of contact "SI***, IM***, SC+++, PSC+++, AM-3.47" PSC 7 -2383.520 4781.040 Secondary contact with two phases of contact "SI***, IMNS" SIex 7 -2234.797 4483.594 Expansion SI*** IMex 9 -2226.699 4471.397 SIex*** "IM***, IM2M2P+++" AMex 10 -2145.733 4311.465 "SIex***, IMex***, SCex+++, PSCex+++" "AM***, AM2M2P+++, AM2N+++, AM2N2M2P+++" SCex 10 -2226.699 4473.398 "SIex**, IMex NS, SCex-0.002" "SC***, SC2M2P+++" PAMex 10 -2114.967 4249.933 "SIex***, IMex***, SCex+++, PSCex+++, AMex +++" "PAM***, PAM2M2P+++, PAM2N+++, PAM2N2M2P+++" PSCex 10 -2226.700 4473.400 "SIex**, IMex NS" "PSC***, PSC2M2P+++" IM2M2P 8 -2244.500 4505.001 Heterogeneity in gene flow across the genome IM*** AM2M2P 9 -2229.833 4477.666 "IM2M2P***, SC2M2P+++, PSC2M2P+++" AM*** SC2M2P 9 -2236.918 4491.835 "IM2M2P***, PSC2M2P+" SC*** PAM2M2P 9 -2229.342 4476.684 "IM2M2P***, SC2M2P+++, PSC2M2P+++, AM2M2P-0.98" PAM*** PSC2M2P 9 -2241.334 4500.668 IM2M2P* PSC*** IM2M2Pex 11 -2142.048 4306.095 Heterogeneity in gene flow across the genome + Expansion "IM***, IMex***, IM2M2P***, IM2N+++, IM2Nex+++" AM2M2Pex 12 -2118.034 4260.068 "IM2M2Pex***, SC2M2Pex+++, PSC2M2Pex+++" "AM***, AMex***, AM2M2P***, AM2N+++" SC2M2Pex 12 -2136.592 4297.184 "IM2M2Pex***, PSC2M2Pex-0.54" "SC***, SCex***, SC2M2P***, SC2N+++, SC2Nex+++" PAM2M2Pex 12 -2112.475 4248.950 "IM2M2Pex***, AM2M2Pex++, SC2M2Pex+++, PSC2M2Pex+++" "PAM***, PAMexNS, PAM2M2P***, PAM2N+++" PSC2M2Pex 12 -2136.864 4297.728 IM2M2Pex** "PSC***, PSCex***, PSC2M2P***, PSC2N+++, PSC2Nex+++" SI2N 6 -2196.623 4405.246 heterogeneity in Ne "SI***, SIex+++" IM2N 8 -2182.470 4380.940 SI2N*** "IM***, IMex+++, IM2M2P+++, IM2N2M2P-4.00" AM2N 9 -2182.417 4382.834 "SI2N***, IM2NNS" "AM***, AM2M2P+++, AM2N2M2P-4.02" SC2N 9 -2179.895 4377.791 "SI2N***, IM2N*, AM2N-5.04, PSC2N-2.50" "SC***, SCex+++, SCM2M2P+++, SC2N2M2P-4.00" PAM2N 9 -2176.357 4370.715 "SI2N***, IM2N***, AM2N++, SC2N+, PSC2N+" "PAM***, PAM2M2P+++, PAM2N2M2P-5.13" PSC2N 9 -2181.144 4380.288 "SI2N***, IM2NNS, AM2N-2.55" "PSC***, PSCex+++, PSC2M2P+++, PSC2N2M2P-4.01" SI2Nex 9 -2180.330 4378.660 Heterogeneity in Ne + expansion "SI***, SIex***, SI2N***" IM2Nex 11 -2172.316 4366.632 SI2Nex*** "IM+++, IMex***, IM2M2P+++, IM2N***, IM2N2M2P+++" AM2Nex 12 -2117.316 4258.633 "SI2Nex***, IM2Nex***, SC2Nex+++, PSC2Nex+++" "AM+++, AMex***, AM2M2P+++, AM2M2Pex-1.45, AM2N***, AM2N2M2P+++" SC2Nex 12 -2171.326 4366.653 "SI2Nex***, IM2NexNS" "SC+++, SCex***, SC2N***, SC2M2P+++, SC2N2M2P+++" PAM2Nex 12 -2086.311 4196.623 "SI2Nex***, IM2Nex***, AM2Nex+++, SC2Nex+++, PSC2Nex+++, " "PAM+++, PAMex***, PAM2N***, PAM2M2P+++, PAM2M2Pex+++, PAM2N2M2P+++" PSC2Nex 12 -2172.088 4368.176 "SI2Nex***, IM2NexNS" "PSC+++, PSCex***, PSC2M2P+++, PSC2N***, PSC2N2M2P+++" IM2N2M2P 10 -2182.472 4384.944 Heterogeneity in Ne + Heterogeneity in gene flow across the genome "IM+++, IMex+++, IM2M2P***" AM2N2M2P 11 -2182.426 4386.851 IM2N2M2PNS "AM+++, AM2M2P***" SC2N2M2P 11 -2179.896 4381.792 "IM2N2M2P*, AM2N2M2P-5.06, PSC2N2M2P-2.51" "SC+++, SCex+++, SC2M2P***" PAM2N2M2P 11 -2176.924 4375.848 "IM2N2M2P***, AM2N2M2P++, SC2N2M2P+, PSC2N2M2P+" "PAM+++, PAM2M2P***" PSC2N2M2P 11 -2181.150 4384.300 "IM2N2M2PNS, AM2N2M2P-2.55" "PSC+++, PSCex+++, PSC2M2P***" "k is the number of parameters and AIC the Akaike Information Criterion. Model comparisons within and between classes of models are shown. Nested models were compared using likelihood ratio tests, with subscripts indicating significance levels (abbreviated ***P<0.001; **P <0.01; *P<0.05, NS non-significant). Non-nested models were compared using AIC with relative likelihood of each model compared to the best model L(Mi|Mbest)=exp((AICmin-AICi)/2) (abbreviated +++L(Mi|Mbest)<0.001; ++L(Mi|Mbest) <0.01; +L(Mi|Mbest)<0.05, L(Mi|Mbest)> 0.05 : AIC difference shown)"