Adult human female and ostrich skeleton, not to scale.
Ostrich engraving originally from Cheselden’s works, included to show analogous structures between the bird and the human. Though the evolutionary significance of homology and analogy of anatomical structures wasn’t understood yet, Linnaeus used many homologous structures in his grouping of creatures within families and species. However, Linnaeus grouped animals based upon morphology, not evolutionary characteristics.
These days, phylogenetics is the science most closely associated with the evolution of homologous structures.
A Series of Engravings Representing the Human Skeleton. John Barclay, 1820.