The greatest effect of the European intrusion into the Americas was to increase the Indian and mestizo population through intermarriage with the whites. The primary cause of the massive population decline among native Americans after the European arrival was not warfare but disease.
Single-issue interest groups focus on advocacy around a single defining issue. These groups focus on a diverse array of issues including abortion, taxation, and animal rights. Because of their singular focus, these groups are known for the intensity of their lobbying.
