A drawing can be more representative than a photograph
A drawing, illustration, or a constructed image can be more representative of a thing than a realistic photograph.
This is true when it comes to books about plants and animals, and also about maps.
Think about the London underground map, how it eschewes geographic information in favour of relationships and connections.
Representing an understanding of something over depicting an instance of it.
‘Although his works are most definitely fiction, they paint a literary picture of the world of espionage that, like the best paintings, exposes the nature of reality much better than the real thing.’
See Sketching vs detail-drawing, ,