Determining the relationship between two species primarily involves analyzing genetic sequence similarities, a method known as cladistics. However, other factors also play a significant role in establishing these relationships. The similarity of reproductive organs, such as flowers and ovaries in plants and animals, is a key indicator. Additionally, specific phenotypic traits, like mammalian teeth structure or pelvis formation, are used, especially in the study of fossils. While genetic analysis is the most reliable method, it is supplemented by morphological comparisons when genetic data is unavailable. The discussion highlights the complexity of species classification, particularly when multiple species exhibit similar genetic characteristics.
