According to Least Cost Analysis (LCA, see Mlekuž (2012) and Verhagen et al., 2019), prehistoric migration probably occurred via the route that offered the Least Cost and duration of travel.

Do you know of any sources that measure LC of sea routes, taking into account the prevailing winds and sea currents? For example, based on LCA, the route from India to England around Africa is "much shorter" than the route from England to India around Africa: The prevailing winds flow approximately from India to the Cape of Good Hope, and from there to Senegal. Due to this, Vasco da Gama sailed first from Europe to South America in order to reach the westerly winds, which then carried him towards Indonesia.

Based on genetic evidence, the British Isles received immigrants from the Indus Valley approximately 700-200 BCE. I am searching for LCA models, that would tell me, which route from India to the British Isles was shortest: 1) The river route via the Caspian Sea, Volga, Karelia, and the Baltic Sea, 2) The route around Africa, or 3) the route via Middle east and the Mediterranean Sea.