of these a few would perhaps at once be able to migrate southwards, by keeping to the cooler currents, while others might remain and survive in the colder depths until the southern hemisphere was in its turn subjected to a glacial climate and permitted their further progress;
hauetariko gutxi batzuk berehala hegorantz migratzeko gai izanen ziren, korronte freskoagoetan iraunez, beste batzuek, ostera, ur sakon hotzagoetan geratu eta bizirautea lortuko zuten artean, harik eta hego hemisferioa ere glaziare-klimaren pean geratu eta aurrera segitzeko ahalbidea eman zien artean;