a Red eft

A blog for stem-bird watchers

Think I'm not looking at every single reblog of that Lion King Dinosaurs post?

assuming-dinosaur:

drawingdinosaurs:

assuming-dinosaur:

seegercove:

You bet your sweet bippies I am. Thank you, everyone. You’re beautiful and I’m so happy that you all love it so much. I’ve got more on the way. Mufasa’s been the hardest one to nail down thusfar, but I think you’re gonna like the one I’ve settled on.

Also! Taking suggestions on…

Evidence seems to be stacking up that Nanotyrannus is a juvenile Tyrannosaurus. So Simba would be a Nanotyrannus.

How about Dryptosaurus for the hyenas?

I also support the idea of Zazu as a mammal.

Exactly why I put the “Dueling Dinosaurs” species forward rather than explicitly saying Nanotyrannus, which is looking like a pretty distinct taxon so far.

I had read that claims of it being a distinct taxon might be more marketing than science. Besides, I’m having trouble finding any information on it other than the auction controversy.

So long as this specimen is for sale, any and all claims about it are nothing but marketing. Science can’t be done here until it’s been sold and studied by an independent team, otherwise, conflict of interest city.

So far, even with all the marketing hype, I haven’t seen anything to indicate his is not just another juvenile T. rex. The arms are proportionately very large, but it’s silly to think the arms grew proportionately in 100% of all tyrannosaurid species. Tarbosaurus started life with very small arms, but Tarbosaurus also has much more reduced forelimbs than even Tyrannosaurus, even as an adult. Additionally, our picture of T. rex forelimbs is still based largely on related species. Even Sue doesn’t have a complete hand. If the “Dueling Dinosaurs” specimen really does have the proportions people claim, all it really means is that T. rex fingers were longer and more robust than we thought, and not that similar to the tiny twig-fingers of Tarbosaurus it’s usually restored with.

Anonymous said: Why has the relative time of the K-Pg extinction changed from 65 to 66 mya? I grew up learning that this extinction took place 65 mya, and then a couple of years ago I started seeing 66 mya more often.

assuming-dinosaur:

archosaurophilia:

drawingdinosaurs:

aurusallos:

I’ve only really seen the 65 mya hypothesis, with maybe some stretchback to 65.5. It can be a little hard to calculate exactly when the event happened since a shift in one million years isn’t that significant. Except, carbon dating???

Someone that knows a little more about this than me should answer this question.

ETA: a few of the sites I’ve looked at so far have said that as of 2013 it was 66 mya… I’m confused now.

I’m willing to bet the 66 mya date is just coming from rounding off 65.5 mya. I’ve been seeing 66 mya more recently too, but I also recall seeing it in a fair amount of older media too, so I don’t think it’s new.

Nah, the ICS (International Commission on Stratigraphy) just redefined the end of the Cretaceous as 66 Ma (was roughly 65.5 before), based on updated studies of stratigraphic data. Since it’s the body responsible for defining these time periods, references have necessarily changed.

http://www.stratigraphy.org/ICSchart/ChronostratChart2014-02.jpg

It isn’t that they redefined the boundary of the Cretaceous—-that boundary is kept pretty constant by the BIG HONKING MASS EXTINCTION—-but that they have updated their estimates of when exactly the rocks that they defined to be the boundary were made.

Yes better dating methods now say this was closer to 66 than to the 65.5 or 65 I grew up with. Science marches on!

beard-and-dinos:

I see something in bird Part II
I did it again D:
Secretary bird became: Secretarioraptor!

Cool, but why give it a human eye…?

(via prehistoric-birds)

kenbrasai:

apsaravis:

Continued from this post.
This is meant to be an avisaur and waterfowls.
Drawn in Manga Studio, coloured in Photoshop.

Enantiornithes did not have retrices (they had ribbon-like tail feathers, that admitely formed a fan in some forms) and their feet were by all accounts fuzzy. Otherwise, it’s good.


True about the rectrices, but there isn’t any evidence that I can recall off the top of my head that all most or even any enants had fuzzy feet. One or two have long tibial feathers that have been erroneously called hind wings in the lit, and there is an unnamed Crato specimen with true hind wings, but I think calling anything but metatarsal feathers hind wings is a major reach, otherwise we need to say most modern birds have them too.

kenbrasai:

apsaravis:

Continued from this post.

This is meant to be an avisaur and waterfowls.

Drawn in Manga Studio, coloured in Photoshop.

Enantiornithes did not have retrices (they had ribbon-like tail feathers, that admitely formed a fan in some forms) and their feet were by all accounts fuzzy. Otherwise, it’s good.

True about the rectrices, but there isn’t any evidence that I can recall off the top of my head that all most or even any enants had fuzzy feet. One or two have long tibial feathers that have been erroneously called hind wings in the lit, and there is an unnamed Crato specimen with true hind wings, but I think calling anything but metatarsal feathers hind wings is a major reach, otherwise we need to say most modern birds have them too.

(via danbensen)

assuming-dinosaur:

Wait… with all of this new information about Deinocheirus, we’re going to need a new mystery dinosaur. 

Any ideas?

We still don’t have most if the actual skeleton of its contemporary Therizinosaurus. Similar situation: big clawed hands, rest of body unknown, inferred from smaller relatives. Possibility for an equal amount of weirdness!

assuming-dinosaur:

drawingdinosaurs:

cmkosemenillustrated:

A recently published photo of its skull suggests that the enigmatic “giant claw” dinosaur Deinocheirus mirificus had a face that roughly looked like this. Wow.
www.cmkosemen.com

Okay, I take back what I said earlier, looks like that thing in the pictures is the skull of Deinocheirus. Wow.

Only if he knows more than we do, so I’m still not sure. In context, it only makes sense for it to be the skull of Deinocheirus, but if it is, boy is it weird. It also looks like it might have an unusually deep lower jaw, though it’s hard to say at this angle.

I’m not sure where all the disbelief is coming from. In top view the skull looks pretty much identical to Gallimimus except for a slightly broader beak which does look a bit Anatosaurus like. But when I first saw the pic where the premax is separated from the max, for some reason I assumed the premax was another bit of bone from the foot and so the remainder of the skull looked almost too normal-ornithomimid to be true!

assuming-dinosaur:

drawingdinosaurs:

cmkosemenillustrated:

A recently published photo of its skull suggests that the enigmatic “giant claw” dinosaur Deinocheirus mirificus had a face that roughly looked like this. Wow.

www.cmkosemen.com

Okay, I take back what I said earlier, looks like that thing in the pictures is the skull of Deinocheirus. Wow.

Only if he knows more than we do, so I’m still not sure. In context, it only makes sense for it to be the skull of Deinocheirus, but if it is, boy is it weird. It also looks like it might have an unusually deep lower jaw, though it’s hard to say at this angle.

I’m not sure where all the disbelief is coming from. In top view the skull looks pretty much identical to Gallimimus except for a slightly broader beak which does look a bit Anatosaurus like. But when I first saw the pic where the premax is separated from the max, for some reason I assumed the premax was another bit of bone from the foot and so the remainder of the skull looked almost too normal-ornithomimid to be true!

cmkosemenillustrated:

A recently published photo of its skull suggests that the enigmatic “giant claw” dinosaur Deinocheirus mirificus had a face that roughly looked like this. Wow.
www.cmkosemen.com

cmkosemenillustrated:

A recently published photo of its skull suggests that the enigmatic “giant claw” dinosaur Deinocheirus mirificus had a face that roughly looked like this. Wow.

www.cmkosemen.com

(via prehistoric-birds)

daggerwrist:

This fossil specimen of the Cretaceous theropod Jinfengopteryx elegans contains a few small round structures that the dinosaur ate before death, probably seeds. This is rare direct evidence for diet in coelurosaurs.

Source 1:
Ji, Q., Ji, S., Lu, J., You, H., Chen, W., Liu, Y., and Liu, Y. (2005). “First avialan bird from China (Jinfengopteryx elegans gen. et sp. nov.).” Geological Bulletin of China24(3): 197-205.

Source 2.

Would be nice to credit the artists in these posts… ;) this one is mine, the Epidexipteryx is by Nobu Tamura.

(Source: arrowtongue, via prehistoric-birds)

http://captainironears.tumblr.com/post/84028301122/i-would-really-like-someone-to-explain-to-me-how

avisuchian:

redeft:

captainironears:

redeft:

captainironears:

I would really like someone to explain to me how birds are literally reptiles. Every time I contest that decision the response I get is basically “people with PhDs say this. you obviously don’t know how to science. here is some jargon which I hope you don’t understand.” and there is no effort made…

Basically, we went and changed literally everything about how we name and classify animals about 20 years ago and didn’t quite get around to alerting the media ;)

The word reptile used to mean ectothermic animal with scales and a three chambered heart.

That definition has been thrown out by most paleontologists and replaced by this: a reptile is any and all animals more closely related to lizards, turtles, and crocodiles than to mammals. This definition happens to include birds.

As you can see this is a totally different concept than the one you and most other people are familiar with. So we didn’t really discover that birds are reptiles, we changed what the word reptile means in order to include birds. Same goes for the word dinosaur.

Another confusing aspect of this name change is that the definition quoted above explicitly does not include mammals, so you may also see people saying the term “mammal-like reptile” is no longer to be used, because under the new definition mammals and reptiles are totally separate groups and the ancestors of mammals are no longer considered reptiles.

Uh hm. Forgive me, but that’s pretty silly. But thank you for explaining.

Can’t really disagree, but it is useful to do things in this way from a paleontological point of view. The features we used to associate with traditional “reptiles” didn’t all evolve at once, and neither did the features of birds, so the question of when something crossed the line between amphibian and reptile or reptile and bird became impossible to answer.

When does a reptile become a bird? When it had an avian lung system? Four chambered heart? Became endothermic, and if so, to what degree? First grew feathers? First flew? Many of these features are impossible to fossilize.

Rather than go back and forth on this forever we switched from a system where one group evolved into another, to one where one group evolves within another and all groups are nested like Russian dolls rather than separated out into boxes.

Therefore, we have impressive sounding statements that are really just semantic tricks, like “birds are dinosaurs” or “birds are reptiles” or even “humans are fish”.

i would argue that they’re more than semantic tricks; statements like that, while somewhat simplified and rather confusing if you’re not familiar with the science, do convey some of the amazing things that we’ve learned about the evolutionary history of life on earth, and at the least intrigue people enough that they ask questions and end up learning, much like OP

for me, the revelation that i am essentially an extremely derived fish was something close to a spiritual experience :P

It definitely gets people interested by making it sound more sensational, but I’d argue that “birds evolved from dinosaurs” is just as informative as “birds are dinosaurs” and less misleadingly based on a major shift in the way we arbitrarily name things. Of course are true in modern classification, but the latter requires more context for people to really understand without it coming across as elitist snobbery as the OP felt.

http://captainironears.tumblr.com/post/84028301122/i-would-really-like-someone-to-explain-to-me-how

captainironears:

redeft:

captainironears:

I would really like someone to explain to me how birds are literally reptiles. Every time I contest that decision the response I get is basically “people with PhDs say this. you obviously don’t know how to science. here is some jargon which I hope you don’t understand.” and there is no effort made…

Basically, we went and changed literally everything about how we name and classify animals about 20 years ago and didn’t quite get around to alerting the media ;)

The word reptile used to mean ectothermic animal with scales and a three chambered heart.

That definition has been thrown out by most paleontologists and replaced by this: a reptile is any and all animals more closely related to lizards, turtles, and crocodiles than to mammals. This definition happens to include birds.

As you can see this is a totally different concept than the one you and most other people are familiar with. So we didn’t really discover that birds are reptiles, we changed what the word reptile means in order to include birds. Same goes for the word dinosaur.

Another confusing aspect of this name change is that the definition quoted above explicitly does not include mammals, so you may also see people saying the term “mammal-like reptile” is no longer to be used, because under the new definition mammals and reptiles are totally separate groups and the ancestors of mammals are no longer considered reptiles.

Uh hm. Forgive me, but that’s pretty silly. But thank you for explaining.

Can’t really disagree, but it is useful to do things in this way from a paleontological point of view. The features we used to associate with traditional “reptiles” didn’t all evolve at once, and neither did the features of birds, so the question of when something crossed the line between amphibian and reptile or reptile and bird became impossible to answer.

When does a reptile become a bird? When it had an avian lung system? Four chambered heart? Became endothermic, and if so, to what degree? First grew feathers? First flew? Many of these features are impossible to fossilize.

Rather than go back and forth on this forever we switched from a system where one group evolved into another, to one where one group evolves within another and all groups are nested like Russian dolls rather than separated out into boxes.

Therefore, we have impressive sounding statements that are really just semantic tricks, like “birds are dinosaurs” or “birds are reptiles” or even “humans are fish”.