alogies of SGDP modern and imputed ancient genomes in our qpAdm 
modelling and first compute f2-statistics using the Twigstats function 
f2_blocks_from_Relate between all populations involved, which we then 
feed to the ADMIXTOOLS2 package70.
Clustering using qpwave. T o overcome challenges with hand-curating 
source groups used in qpAdm modelling, we follow ref. 5 and run  
qpwave using Twigstats between pairs of ancient individuals. We use 
Han Chinese individuals from Beijing and five European populations 
from the 1000GP as reference groups. This approach tests whether two