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Messages - DaveGodfrey

1
Here is another point in the article:
Quote
One thing that argues against the volant ancestry of these groups is the
propubic pubis. A retroverted pubis would be better for flying ecause it
makes a airfoil ( convex dorsally and concave ventrally )  shape of the
body. A propubic pubis would create a reverse-airfoil, which would not
be advantageous for flying because it would not create lift and the
"bird" would divebomb to the ground! Paul ( 1988 ) argued that the
propubic pubis was a reversal, which it may well be, but there is no
reason why that these groups should evolve a propubic pubis.
It seems to me that a ground-based, secondarily flightless creature would want a pubis that would keep it from rising up into the air. So I do not understand the point the author is making.
Can anyone help with this?
Perhaps someone will come along.
The bottom line is that the oviraptorosaur pubis is not contradictory to the idea that oviraptorosaurs were secondarily flightless.

In fact there is no evidence that contradicts the idea that oviraptorosaurs were secondarily flightless*. And in fact a few studies have actually supported that idea.
And plenty of other studies have given us no reason to think that they were because of where they place them relative to animals which we have reason to think were capable of limited flight.
2
I just realized the absurd interpretation Faid is making of what I posted.
I should have said It seems to me that a ground-based, secondarily flightless creature would want a pubis that would keep it from rising up into the air when it was running.
I assumed everyone understood that.

We did. It was still a fucking stupid thing to say. Do ostriches regularly sorta-takeoff and fall over? Because they have retroverted pubes like every other living bird.

Quote
I forgot about Faid. No doubt we will now be treated to a litany of absurd excuses and rationalizations from folks here.

What "absurd excuses" are you expecting? Because the only one I can think of is "you are an idiot who is incapable of expressing themselves in a clear manner, and says utterly idiotic things without thinking them through". And there's nothing "absurd" about that idea. "Mr When we look inside the eukaryote what do we see?"
3
http://dml.cmnh.org/1998Apr/msg00125.html
Quote
Paedomorphosis is the mechanism that makes flightless birds flightless.
It is seen in all flightless birds that we know to date. Indisputedly,
this is the feature that makes birds flightless and it has been proven
in laboratory studies where the thyroid was taken out of juvenile birds
and they began to exhibit retarded development in the form of the
feathers, forelimb, shoulder girdle, hindlimbs, and behavioral changes.
How these paedomorphic trends work in birds is when species gets
isolated ecologically, geographically, or both they get turned to
selective advantage. Usually birds turn flightless on islands or areas
with few predators, so flight is not necessary. Taking of new ecological
niches has also been considered a compelling reason ( See Feduccia 1996;
Dawson et al. 1994; Olson 1973. for further review on the points above).

This biogeographic isolation would be unlikely to happen in the Late
Jurassic or Early K because Pangaea was just beginning to break apart
and there were few islands to get isolated on
. Ecological isolation may
have been unlikely, but there is no evidence that we know of now.

https://en.wikipedia.org/wiki/Pangaea
Quote
Pangaea or Pangea ( /pænˈdʒiːə/[1]) was a supercontinent that existed during the late Paleozoic and early Mesozoic eras.[2][3] It assembled from earlier continental units approximately 335 million years ago, and it began to break apart about 175 million years ago.

https://en.wikipedia.org/wiki/Oviraptorosauria
Quote
Oviraptorosaurs
Temporal range: Cretaceous, 130-66 Ma

This seems to indicate that his argument against secondarily flightless oviraptorosaurs concerning "few islands to get isolated on", does not stand up.
In fact if you consider the timing you see that as Pangea breaks apart, islands would likely appear and would be new places for oviraptorosaurs to become secondarily flightless.
The breakup of Pangaea was a long and complicated process. Oviraptorosaurs are only known from Laurasia. If you first learn when Laurasia broke apart you might avoid making a fool of yourself.
4
Here is another point in the article:
Quote
One thing that argues against the volant ancestry of these groups is the
propubic pubis. A retroverted pubis would be better for flying ecause it
makes a airfoil ( convex dorsally and concave ventrally )  shape of the
body. A propubic pubis would create a reverse-airfoil, which would not
be advantageous for flying because it would not create lift and the
"bird" would divebomb to the ground! Paul ( 1988 ) argued that the
propubic pubis was a reversal, which it may well be, but there is no
reason why that these groups should evolve a propubic pubis.
It seems to me that a ground-based, secondarily flightless creature would want a pubis that would keep it from rising up into the air. So I do not understand the point the author is making.
Can anyone help with this?
Perhaps someone will come along.
Nah, mate, you're on your own with that one.

Ostriches still have the reverted pubis. Do you think they're in danger of taking off?
5
At a guess, Oviraptor would be an "advanced form". As for what he means by "more bird-like", why don't you read the references he gives, rather than asking "people here" who you clearly have nothing but disdain for?

I'd suggest asking him yourself, but we all know that he's banned you from his blog for your prior behaviour.
6
Which of the long words are you having problems understanding?
7
That would depend in the characters they are discussing now wouldn't it? Perhaps you would like to find out? You're a big boy now, you can do it yourself.

If they're ones unrelated to flight, then it doesn't mean anything much. If they're ones associated with flight in birds, and which you think should be present in "basal Pennaraptora", then according to you they first lost these characters, and then re-evolved them. Which isn't very parsimonious now is it?
8
No, it really doesn't. If it did you'd be able to explain why without throwing out idiotic ideas about "saltations", and completely ignoring the existence of other maniraptorans, or the fact that they were recognised as dinosaurs decades before anyone realised how closely related they might be to birds.

You'd actually be able to answer the questions put to you, rather than declaring things from your comfy chair without ever once looking at a fossil.
9
Does Sucky understand that birds are pennaraptorans?

And to answer his question, because things that aren't pennaraptorans, but are very closely related  are terrestrial and show no adaptations for flight. As do many paravians. 
10
Because all oviraptorosaurs were also "ground-based creatures", as were a very large number of paravians. As are all the animals that group closely to Pennaraptora.
11
What about the characters within Paraves that oviraptorosaurs do not have? Especially the ones that have nothing to do with flight, like egg morphology?

The reason the characters are listed where they are is because of how they're distributed. If you wanted to put oviraptorosaurs within Paraves (or rather move some members of Paraves out and into a position basal to Pennaraptora, you would need to list different characters, because their distribution would be different. Those characters would not be diagnostic of a Paraves that included oviraptorosaurs because they don't have them.
12
Quote
It is mainstream thinking that ground-based dinosaurs evolved into feathered  ground-based creatures which then evolved into basal Paraves. But that idea is greatly weakened if Oviraptorosaurs were secondarily flightless.
If Oviraptorosaurs were secondarily flightless then basal Pennaraptora were flying/volant. What did flying/volant basal Pennaraptora evolve from? 
Can anyone here acknowledge that flying/volant basal Pennaraptora must have evolved in a saltation from ground based dinosaurs, if Oviraptorosaurs were secondarily flightless?
Anyone? As an alternative you could describe the evolution from ground-based dinosaur to flying/volant basal Pennaraptora. And if you can support your thinking with reference link(s) and copy and paste that would also be helpful.
Well we have come to the Achilles Heel of the dino to bird theory. For the dino to bird theory to be correct there must have been a gigantic saltation that occurred between the ground-based dinosaurs and the flying/volant feathered creatures.
Worth repeating:
Anyone? As an alternative you could describe the evolution from ground-based dinosaur to flying/volant basal Pennaraptora. And if you can support your thinking with reference link(s) and copy and paste that would also be helpful.

You are the folks who are pretending to be knowledgeable about the dino to bird theory.
Since you folks need help consider this:
Notice the characteristics that appear at Pennaraptora and Paraves. This is the saltation required.
https://www.researchgate.net/publication/269715801_An_integrative_approach_to_understanding_bird_origins


Notice that the characteristics listed for pennaraptora and paraves are not present earlier. This is the saltation I am referring to. The saltation from ground-based dinosaurs to the flying/volant creatures of pennaraptora/paraves.
Its called "evolution" dickhead. You can find characters like that for every clade you want. Hey look, there are a bunch of things unique to whales. Therefore whales cannot be mammals, and must be ichthyosaurs. Never mind the fact that there are a ton of characters unique to mammals that you do see in whales, but are clearly absent from ichthyosaurs.

Or bats? What about the characters in bats that we don't see in other mammals? Or flowering plants. There are clearly a bunch of unique characters there. There must have been some kind of saltation. Therefore they cannot have evolved from gymnosperms, and must be descended from coral. They photosynthesise, and have "petals".
13
No, I can't acknowledge something that you have declared to be true with no supporting evidence. And what of the saltation between pterosaurs and "basal pennaraptorans"? Just because you think both could fly doesn't mean there aren't huge differences between the two groups.
14
Quote
Also note that if basal Pennaraptora are flying/volant then the oviraptorosaurs became ground based AFTER branching from basal Pennaraptora. Consequently they provide NO evidence of an ancestor/descendant relationship between dinos and birds.

Does anyone understand that if basal Pennaraptora are flying/volant then the oviraptorosaurs became ground based AFTER branching from basal Pennaraptora?

In the dino to bird theory Pennaraptora is imagined to be a ground-based transitional between actual dinosaurs and Paraves. Do people understand that?

No, it isn't. Pennaraptora is the group comprising both Paraves and Oviraptorosauria. Some of them are "ground-based", like Velociraptor. Some of them are clearly powered fliers, like pigeons,  and some  of them are secondarily flightless like dodos. Whether the earliest members of the group was capable of flying or not is unknown. But that doesn't stop them being dinosaurs. Because dinosaurs aren't classified based on whether they could fly or not, but on details of skeletal anatomy that are clearly present in maniraptorans.
15
Also note that if basal Pennaraptora are flying/volant then the oviraptorosaurs became ground based AFTER branching from basal Pennaraptora. Consequently they provide NO evidence of an ancestor/descendant relationship between dinos and birds.
Nope, that doesn't follow at all. What about all the things they have in common with dinosaurs that aren't directly related to locomotion? Do you think these unfound, unknown animals spent all their time airborne and never walked around on land? Because that would be stupid.

Bear in mind that that illustration is only dealing with the characters we think of as being "birdy". And not a ton of other things that allow you to recognise, for example, a vertebra as belonging to a theropod. And not a crocodile. You need to take into account those characters, and its those that show birds are dinosaurs.
16
 Perhaps idiot boy would care to enlighten us as to why egg characters would change in "basal Pennaraptora" if they had some kind of flight capability?
17
If basal Pennaraptora is flying/volant then all the characteristics now attributed to Paraves would be found in basal Pennaraptora. But if someone thinks that a particular characteristic now attributed to basal Paraves would not be found in flying/volant basal Pennaraptora please let us know and if you can support your thinking with reference link and copy and paste all the better.
No, you're the one saying that they would. You need to support your contention.

Hop to it.
18
The lout Dave Godfrey does not understand cladistics. He thinks that the characteristics attributed to Pennaraptora are observed. Of course they are not observed. All that is observed are the characteristics of the fossils included in the cladistic analysis.
The characteristics of Pennaraptora are hypothetical.
Is everyone confused about this point?
How would the list differ if Pennaraptora was flying/volant? Here is a clue - look at the characteristics attributed to Paraves. Which ones of those would not be attributed to Pennaraptora, if Pennaraptora was flying/volant?

Remember that if basal Pennaraptora were flying/volant, oviraptorosaurs were SECONDARILY flightless.

I checked the list.

I cannot find a single one that would somehow "change".

Perhaps "socrates" would like to clarify?
One might predict that asymmetric vaned feathers would turn out to be a more primitive character than currently thought if Oviraptorosauria was secondarily flightless. However there's no evidence that they are yet. So its a character that is currently restricted to Paraves, and not seen elsewhere. Until such time as it shows up in either a really basal oviraptorosaur, or in a non-pennaraptoran maniraptoran, its a perfectly good apomorphy of certain members of Paraves.

But those are predictions. They are not observations.
19
The lout Dave Godfrey does not understand cladistics.

He does actually. The idiot Socrates1 on the other hand doesn't seem to be able to read a phylogenetic tree.

Quote
He thinks that the characteristics attributed to Pennaraptora are observed. Of course they are not observed. All that is observed are the characteristics of the fossils included in the cladistic analysis.

The fossils that are placed as members of Pennaraptora possess those characters. Therefore they are observed to be present in members of Pennaraptora, but not in other clades. So that's why they're marked at the node. Because they characterise members of the clade designated by that node.
20
It wouldn't. That list is a list of observed characters.
21
Following is a revised list, based on feedback received from JonF ...

1) The poop in Rampart Cave Unit A is almost entirely Shasta ground sloth poop with very little of any other kind of feces.  That animal is now extinct.
2) Two ways to study the pooping habits of an extinct sloth would be (a) study the poop itself and (b) study the pooping habits of the closest living relative
2b) Wikipedia describes the (modern) "Sloth" ... link here ... https://en.wikipedia.org/wiki/Sloth
3) If we read the Wiki Sloth article, we find some curious things ... (a) modern sloths only poop about once a week (b) when they poop, they do so in the same spot over and over again (c) they poop out about 1/3 of their body weight each week
4) From the data given in the Long paper, the info in (3) above and applying a scale factor to scale up from "modern sloth" to the size of a Shasta sloth, we could calculate what would be required for one "Shasta sloth sized modern sloth" to deposit Unit A
5) This has been done by myself with the help of osmanthus and the result is that Unit A represents roughly "15 sloth years" of weekly, year round pooping of one adult Shasta sloth ... or "60 sloth years" of weekly, seasonal pooping (3 months of Spring only)
6) Unit A was supposedly deposited over a 2000 year time frame (not 1500, Faid) determined by carbon 14 (p.1844 first sentence of last paragraph in LH column)
7) Carbon 14 dating ignores theories of catastrophic global resurfacing events within the past 10,000 years.
8.) There is a difference in flora found in the upper part of Unit A compared to the lower part with more succulents being in the lower part

I eliminated Point 9 as it was redundant and I modified the others to be more FACTUAL.

Are we in agreement on these points?
NO.

"2) Two ways to study the pooping habits of an extinct sloth would be (a) study the poop itself and (b) study the pooping habits some extant animal that we can establish as analogous".

(Which would be one hell of a trick).

2b and 7 are true but irrelavent.

You left out quite a few relevant facts, such as the dark band contained in unit A.

So, is this your formal abandonment of any attempt to discuss Brown's model, Steve's model, or the real tests of Brown's model?
You say "NO" we are not in agreement ... but then you say "2b and 7 are true but irrelevant."  If you think they are true, how can you not be in agreement?  Also you want me to list an item about the dark band ... ok ... Are you talking about the "Guano Layer" item in Figure 1 on the right side?  If so, fine I can add that.

No I'm not abandoning anything.  Just separating out this topic for better clarity.
Because 2b is about living sloths, and therefore fucking useless when discussing extinct sloths with a totally fucking different ecology.
22
If you're describing the "dino to bird phylogeny" then there would be no difference. It isn't going to change just because Oviraptorosauria might have had an ancestor with some flight capability.

If you think it would then show your working. Or admit that you don't know. Your choice "prof".
23
Why do you think it would look any different?
24
No Sucky, I don't know what the phylogeny would look like. You need to tell us exactly what taxa are in "Euparaves" and what aren't. You don't have a "flying ancestor" for this group, other than, I assume Yi qi, but that's clearly a basal paravian, and therefore Oviraptorosauria are independently flightless of dromaeosaurs, so your "flying ancestor" needs to show up further down the tree than that.

Then you need to get off your arse and actually produce a tree. You claim to have the software. Create your data matrix and get on with it.
25
If Oviraptorids and other feathered, ground-based creatures were secondarily flightless, what would the revised phylogeny look like?
Why do you think it would look any different? What animals do you think are more basal in the cladogram than ornithomimosaurs? (Are they also secondarily flightless? Ifsoshow your evidence to support this). What phylogenetic analysis have you done that supports such a rearrangement?