What is nativism? What are examples of this during antebellum america?

In the US, nativism is the policy of protecting the interests of native-born or established inhabitants against those of immigrants. In philosophy, it’s the theory that concepts, mental capacities, and mental structures are innate rather than acquired by learning.

High yielding varieties of wheat.

Explanation:

The father of the Green revolution as often called, Dr. Norman Borlaug was an American Scientist who was awarded Noble prize for his research. He invented high yielding varieties of wheat which combined with modern agriculture techniques which are used extensively in Mexico and India. It not only solved the problem of food security at home but made these nations wheat exporters.