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Re: another dumb question: Terror Birds are not dinosaurs?



That message got sent to the list several times now, always without a single line break, so many list members can only have got the "message truncated" error. (Did the text get shuffled between different programs or operating systems?)

I hope I put the line breaks in the right place:

Eike wrote about phorusrhacids:

> And: they might not be Gruiformes (cranes and rails
> and some others). Hasn't been analyzed yet, but the
> groups of birds unequivocally accepted as Gruiformes
> nowadays all originated in Laurasia IIRC, that is
> Eurasia + North America. Terror birds evolved in South
> America, which at their time was still separate. Not> as far as to > preclude a gruiform relationship, but far
> enough to make it disputable. Presumed European
> relatives have been moved out of the group. Thus,
> their relationships need restudy, this aspiring
> student of all things avian say.


What you say there is not completely true; while you are right that Aenigmavis, which was postulated to be a basal phorusrhacid is no longer regarded as such but rather as a sophiornithid, that is a basal strigiform, that does not mean no phorusrhacid relatives are known from Palaeogene Laurasia. In fact, quite a few bathornithids and idiornithids are known from this time and these are part of Cariamae, just like Titanis and kin. It rather seems that the latter, and perhaps seriemas too, were a southern branch of this group that proved in the long run just a little more succesful then the northern clade which seems to have disappeared by Neogene times.That said, I agree that Cariamae probably have little to do with traditional Gruiformes. The proposed Metaves/Coronaves split is highly interesting and especially regarding 'Gruiformes'. Kagu, sunbittern and mesites are in Metaves whereas the rest is in Coronaves. Of these, seriemas (and thus Cariamae) are far from the others and placed in a, if accurate, highly interesting clade consisting of them, passeriforms, falcons and psittaciforms. It surprises me no one has yet given this clade a name (as far as I know), as it is a lovely clade indeed.

_DM:_ Nobody else has found that clade in an analysis yet. I think that's why it hasn't been named. If everyone starts finding it, it will certainly be named.


Anyways, in all probability you are right in saying that Gruiformes is probably paraphyletic. And in fact, over the years it has gradually eroded. For those with rusty knowledge or not quite in the know, this is the deal:

Traditional Gruiformes:
Gruidae (cranes)
Aramidae (limpkin)
Psophiidae (trumpeters)
Rallidae (Rails) (Sometimes regarded as a different 'order' and it is possible that in the future, Himantornis will be awarded its own family)
Heliornithidae (finfoots) (probably closest to rails)
Rhynochetidae (kagu) (possibly Metaves and thus something else entirely)
Eurypygidae (sunbittern) (same story)
Mesitornithidae (mesites) (same story)
Cariamidae (perhaps closest to parrots, passeriforms and falcons)
Turnicidae (buttonquails) (Charadriiformes)
Pedionomidae (plains-wanderer) (Charadriiformes)