Many Iberian colonists in the viceroyalties of New Spain (Mexico) and La Plata (Argentina) practiced cattle ranching. Both sides practiced branding and rode horses to control their herds. Many of the colonists, and their breeding stock, were Andalucian in origin.
During the colonial period, how did these two cattle cultures diverge? (One factor of which I am already aware is that La Plata cowboys adopted Incan-style bolas.)