Linked from

The 18 pages that link to Species problem, each with the reason it gives.

• Homo habilisRelated: Fragmentary fossils make the boundaries of Homo habilis contested.

• Homo heidelbergensisRelated: Fragmentary remains make it difficult to decide which fossils belong to this species.

• Species conceptRelated: It arises because no single boundary rule fits every organism and evolutionary history.

• Hominin taxonomyRelated: No single species definition resolves every fossil hominin boundary.

• Australopithecus sedibaRelated: The limited sample makes the boundaries and variation of this fossil species difficult to assess.

• Ernst MayrRelated: Mayr’s reproductive-isolation definition remains influential but cannot straightforwardly cover every lineage.

• History of biologyRelated: Changing species concepts reveal persistent limits in classifying life's diversity.

• Homo ergasterRelated: Sparse and variable fossils make the boundary between Homo ergaster and Homo erectus contested.

• Australopithecus bahrelghazaliRelated: A small number of fossils makes the species' distinctness difficult to evaluate.

• Australopithecus deyiremedaRelated: Limited fossils make the distinctness of this species a question of classification.

• Georges-Louis LeclercRelated: Buffon’s emphasis on reproduction and variation challenged fixed, purely classificatory accounts of species.

• KenyanthropusRelated: A single damaged skull makes the genus’s boundaries hard to test.

• PlatypterygiusRelated: Fragmentary fossils make it difficult to decide whether named Platypterygius forms are distinct species.

• ProtistologyRelated: Asexual reproduction and cryptic diversity make protist species boundaries especially challenging.

• Red Deer Cave peopleRelated: The fossils show why anatomical distinctiveness alone may not establish a species.