Modern bird palates

[morfrain_encilgar]

Part of the problem with the origins and relationships of different groups of ratites (ostrich-like birds) is their palate, which is similar to that found in tinamous, but different to the types of palate which are found in other modern birds. It has been suggested that the palate condition of ratites is paedomorphic and that they mignt be unrelated to one another.

Here, it is found that the shape of the palate morphology of ratites is not paedomorphic. A tinamou's palate does resemble that of an immature chicken, but only in its later stages of development, and is inbetween the ratites and the other birds.

[Stríbog]

The relationship of ratites has been hotly debated for some time, owing to the confusion over whether they arose separately on several continents (rheas in South America, ostriches in Africa, cassowaries and emus in Australasia) or whether they descended from a common ancestor. I'm surprised someone hasn't done a thorough intra- and inter-generic genetic analysis of ratite populations.

[morfrain_encilgar]

The relationship of ratites has been hotly debated for some time, owing to the confusion over whether they arose separately on several continents (rheas in South America, ostriches in Africa, cassowaries and emus in Australasia) or whether they descended from a common ancestor. I'm surprised someone hasn't done a thorough intra- and inter-generic genetic analysis of ratite populations.

Well, they probably have done that.

There's actually very little evidence, that ratites are unrelated to each other. Its settled that they are, but its still unknown wether flightlessness arose more than once, or wether they became flightless at different times, like rails have.

[Stríbog]

Well, they probably have done that.

There's actually very little evidence, that ratites are unrelated to each other. Its settled that they are, but its still unknown wether flightlessness arose more than once, or wether they became flightless at different times, like rails have.

Of course flightlessness arose independently several times, just as flight itself did. Penguins and ratites are obviously not closely related, yet both are flightless. Similarly, Protoavis and Archaeopteryx evolved flight millions of years before flight "permanently" took hold as later theropods gave rise to true birds.

[morfrain_encilgar]

Of course flightlessness arose independently several times, just as flight itself did. Penguins and ratites are obviously not closely related, yet both are flightless. Similarly, Protoavis and Archaeopteryx evolved flight millions of years before flight "permanently" took hold as later theropods gave rise to true birds.

I was referring to flightlessness in ratites, the penguins being related to Gaviids and to tubenoses. Some types of bird become flightless more often than other birds do, like the rails, and its not known wether ratites had an ancestor that could fly, or was already flightless.

Now theropod phylogeny is uncertain and I can't say I'm an expert on that, but Protoavis seems to be a mix of different animals and Archeopteryx seems to be similar to flying Cretaceous dromaeosaurs. And, Archeopteryx really isn't much older than the fathered dinosaurs of China.

[Stríbog]

I was referring to flightlessness in ratites, the penguins being related to Gaviids and to tubenoses. Some types of bird become flightless more often than other birds do, like the rails, and its not known wether ratites had an ancestor that could fly, or was already flightless.

Now theropod phylogeny is uncertain and I can't say I'm an expert on that, but Protoavis seems to be a mix of different animals and Archeopteryx seems to be similar to flying Cretaceous dromaeosaurs. And, Archeopteryx really isn't much older than the fathered dinosaurs of China.

As I understand it, Archaeopteryx was Late Jurassic and the earliest dromaeosaurs were early Cretaceous. Protoavis was late Triassic, a bit of an anomaly.

[morfrain_encilgar]

As I understand it, Archaeopteryx was Late Jurassic and the earliest dromaeosaurs were early Cretaceous. Protoavis was late Triassic, a bit of an anomaly.

Protoavis probably didn't exist but Archaeopteryx isn't much older than the first dromaeosaurs, which seem to have had flying ancestors themselves.