When the dodo was alive there was no photography, so we don't know exactly what it looked like. This is quite a modern drawing of a dodo but it was based on older paintings of the bird. Do you think it is a realistic drawing?
By looking at the skeleton of the dodo and building on that, we probably get a better idea of what the dodo really looked like. If you were to draw a dodo, would you want to work from old paintings, or would you start from scratch and draw the bones on display in the Museum?