Quote by William Bartram
Animal substance seems to be the first food of all birds, even the granivorous tribes.
Summary
This quote suggests that animal substances, such as insects or worms, are the initial source of food for all types of birds, including those that primarily eat seeds. It implies that even though birds may primarily consume grains or seeds as their main diet, they still rely on animal-based food initially, possibly to meet their high protein requirements or to provide essential nutrients for survival.