Question

Why are baboons, sparrows, and human beings considered both primary and higher order consumers?

Answer 1

Baboons, sparrows, and human beings are considered both primary and higher order consumers because they all eat plants and meat. 
Primary consumers feed on producers/ plants. Then secondary consumers feed on primary consumers.
 

Answer 2

This is because a primary consumer is an animal that eats plant matter (called a herbivore). 

A secondary consumer is an animal that eats those herbivores but it may also consume plant matter. 

That is why all 3 are considered both.