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Cretaceous hookbill birds?


Still_human

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24 minutes ago, Tidgy's Dad said:

I don't know of any. 

Most of the bird beak shapes evolved after the K-Pg extinction event.

https://www.audubon.org/news/a-beak-boom-millions-years-ago-created-diversity-bird-bills-we-know-today

I could easily be misunderstanding that, but isn't it saying that the boom seemed to happened BEFORE the KT? It says the event likely happened 65-80mya, but does that mean the boom happened before the KT, and the slow process was from then on? If it happened around 65mya then that could mean the boom happened following the KT, but if it was any longer that would mean it was prior. Am I understand the  article correctly, or am I off-base?

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It says somewhere between 65 and 80 million years ago, but they are assuming that it occurred nearer the extinction as this allowed diversification to exploit new habitats and food sources. 

Life's Good!

Tortoise Friend.

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2 hours ago, Tidgy's Dad said:

It says somewhere between 65 and 80 million years ago, but they are assuming that it occurred nearer the extinction as this allowed diversification to exploit new habitats and food sources. 

Yeah, that make perfect sense.

I actually got the impression that they think there's a good chance it began before the KT. I would imagine it was common for lots of types of creatures to have a boom following the KT. I didnt see anything about how long they think the boom went on, but I guess if it didn't start until after the KT, it may have been a pretty short period of time for a significant evolution. If they mean 65-80mya as the entire encompassing period, it would mean there was no more than a million years for the boom to take place. I also didn't see anything specifying this or not, but I guess they could have been referring to the 65-80mya as just the start of the boom, and that it could have continued for...however long, and possibly just slowly decreased down to the steady evolutionary wave, and didn't really have a definitive "end".

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It started as soon as birds existed and began to evolve slightly different beaks, which they did,slowly, but the huge explosion, the 'boom' of new and massively different designs seems to have occurred quite rapidly, possibly just after the extinction. This is quite normal, there is always a fast, varied evolution of many of the survivors to fill evolutionary niches after any extinction, particularly the big ones that leave so many situations vacant. After a few million years, the spaces are filled, in this case , not necessarily by birds, but other creatures (bats for example?) so there is no more room to fill that doesn't have competition. 

After that we see a slow down in evolution, which is a refining of the adaptations that have already evolved with minor bursts when there have been smaller extinctions. 

Life's Good!

Tortoise Friend.

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Pseudastur and its cousin from the Green River Fm (I can't recall its name) are the oldest known parrots with good skeletons (including beak).  And they do not have typical parrot hook shaped beaks.  That came later.  There is a supposed Cret parrot from the Lance, but it is only a lower jaw, and only the top of it.  Many paleo-ortnithologists do not think it is a parrot, and I do not believe this individual bone shows any hint of a curvature to the upper jaw.  Tynskya from the GRF is supposedly an ancestral raptor, and its beak is curved.  

 

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.526.8896&rep=rep1&type=pdf

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1 hour ago, doushantuo said:

Pseudastur,one of the better-documented fossil parrots(Messel/Germany/Eocene)

yosmphfyqsoloeud4tww3gyesllifernakristleanthc.jpg

 

 

Please tell us the source of these figures.  Many interested viewers and potential researchers will certainly benefit, as well as a basic courtesy to the author(s) who expended all the hard work, time and energy necessary to publish it. 

image.png.a84de26dad44fb03836a743755df237c.png

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mayrj.1096-3642.2002.00042.x (1).pdf

Zoological Journal of the Linnean Society, 2002, 136, 715–729.

 

On the osteology and phylogenetic affinities of the Pseudasturidae – Lower Eocene stem-group representatives of parrots (Aves, Psittaciformes)
GERALD MAYR
less than 3MB

 

edit: emended to Pseudasturides by Mayr himself,it seems:

MAYR, G. (2004): Pseudasturides n. gen., a replacement name for the stem group parrot Pseudastur MAYR 1998 (preoccupied by
Pseudastur BLYTH 1850). - Senckenbergiana lethaea, 83 (1/2): 2. 

 

 

 

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On 9/19/2018 at 10:28 PM, doushantuo said:

Pseudastur,one of the better-documented fossil parrots(Messel/Germany/Eocene)

 

yosmphfyqsoloeud4tww3gyesllifernakristleanthc.jpg

lol people from china try to sell, sadly probably successfully, awful reproductions of these, claiming them as authentic. They're usually laughable quality, too.

 

wow, I never knew these were parrots. Such a non-"parrotical" beak

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WAAAAAAAAAAAAITWAITWAITWAIT!!!!! Aren't birds descended from dinosaurs? If that's the case, how can there possibly have been any birds during the Mesozoic, alongside dinosaurs????? It can't be convergent evolution, because they wouldn't all be considered birds, the different evolutions would be different kinds of animals.

This is such a blatantly obvious problem with either birds being around in the Mesozoic, or birds descending from dinosaurs, that I feel like I must be losing my mind right here....what am I forgetting or missing, that fits the 2 together??? 

To be honest, until this came up days ago, I didn't think there WERE birds until after the Cretaceous, but according to the stuff Ive been reading from here, and none of you guys questioning it, it seems like it must be the case.

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Wow, I feel absolutely idiotic! I always assumed Dino's evolved into birds after the KT extinction, and I swear that's how lots of shows portray, and explain it, but Ive known all about some Cretaceous birds, like hesperonis, so somehow I just never put 2&2 together that the evolution had to have happened long before the KT! DUH!

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