Though traditionally considered a suborder within Gruiformes, both morphological and genetic studies[3] show that it belongs to a separate group of birds, Australaves, whose other living members are Falconidae, Psittaciformes and Passeriformes.

[5] However, some researchers like Darren Naish feel that this assessment is biased towards the more well known, predatory representatives of the clade,[7] and indeed at least one form, Strigogyps, appears to have been herbivorous.

This specimen, which dates to the late Cretaceous period 66 million years ago, was originally reported as indistinguishable from the femurs of modern seriemas, and belonging to a large bird about 1 metre (3.3 ft) tall.

[9] However, a subsequent study published by West et al. (2019) reinterpreted this specimen as a fossil of an unnamed large-bodied member of a non-cariamiform genus Vegavis.

[10] In 2024, two ungual phalanx specimens from the early Eocene strata in Antarctica have been identified as those of a cariamiform, possibly of a phorusrhacid.