Final answer:
The Basseri subsist on dairy products from their livestock but also supplement their diet with other food sources obtained through small farming and trade.
Step-by-step explanation:
The Basseri people primarily rely on dairy products from their livestock for subsistence. However, they also supplement their diet with other food sources to meet their nutritional needs. Historically, other pastoralist groups, such as the Bedouin, have supplemented their animal-based diet with cultivated plants obtained through small farming and trade. Contemporary pastoralists often find it necessary to supplement their diet with vitamins and carbohydrates from plant foods, which they obtain through small-scale farming and trade. Similarly, archaeologists have found that many groups combining pastoralism with farming engage in trade with neighboring farmers to exchange animal products for grains and vegetables. In summary, while the Basseri subsist mainly on dairy products from their livestock, they also supplement their diet with other food sources such as cultivated plants obtained through small farming and trade.