Lufengosaurus parental feeding of young (free pdf)

[Ben Creisler]

Ben Creisler

bcre...@gmail.com

A new paper:

Free pdf:

Robert R. Reisz, Timothy D. Huang, Chuan-Mu Chen, Shu-Ju Tu, Tung-Chou Tsai, ShiMing Zhong, Ethan D. Mooney & Joseph J. Bevitt (2024)
Parental feeding in the dinosaur Lufengosaurus revealed through multidisciplinary comparisons with altricial and precocious birds
Scientific Reports 14: 20309
doi: https://doi.org/10.1038/s41598-024-70981-8

https://www.nature.com/articles/s41598-024-70981-8
https://link.springer.com/article/10.1038/s41598-024-70981-8



Previous studies arguing for parental care in dinosaurs have been primarily based on fossil accumulations of adults and hatchlings, perinatal and post-hatchlings in nests and nest areas, and evidence of brooding, the majority of which date to the Late Cretaceous. Similarly, the general body proportions of preserved embryonic skeletons of the much older Early Jurassic Massospondylus have been used to suggest that hatchlings were unable to forage for themselves. Here, we approach the question of parental care in dinosaurs by using a combined morphological, chemical, and biomechanical approach to compare early embryonic and hatchling bones of the Early Jurassic sauropodomorph Lufengosaurus with those of extant avian taxa with known levels of parental care. We compare femora, the main weight-bearing limb bone, at various embryonic and post-embryonic stages in a precocious and an altricial extant avian dinosaur with those of embryonic and hatchling Lufengosaurus, and find that the rate and degree of bone development in Lufengosaurus is closer to that of the highly altricial Columba (pigeon) than the precocious Gallus (chicken), providing strong support for the hypothesis that Lufengosaurus was fully altricial. We suggest that the limb bones of Lufengosaurus hatchlings were not strong enough to forage for themselves and would likely need parental feeding.

[Jura]

I wonder how the authors handled the apparent contradiction of extended parental care and feeding in sauropodomorphs with all the other lines of evidence that indicate no or limited parental care in this group.

*reads paper*

Ah, so they just ignore it.

[Mike Taylor]

Let's not forget that "this group" is a very broad church. Asking whether sauropodomorphs as a group were precocial or altricial is a bit like asking whether mammals are. They conclusion can be true of Lufengosaurus without generalising.

-- Mike.

--
You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/387df1fe-906a-47c6-ad0b-9de11b162848n%40googlegroups.com.

[Gregory Paul]

Quite  correct. Unfortunately because of the anti-scientific convention of no longer taxonomically directly recognizing grade as well as clade, prosauropods which are radically different from their elephantine sauropod relations are chucked together as sauropodomorphs, sort of how humans and Raranimus are all therapsids. Most adult sauropods were too titanic to care for their wee little offspring, and trackways show that juveniles did not join up with adults that might have not even been the same species until they had reached a tonne or so and could keep up without being stomped upon. That parenting prosauropods of just a couple of tonnes would guard their nests and then feed the nestlings is plausible, similar to what hadrosaurs seemed to have done. Whether young prosauropods would have later stayed with their parents in herds is open to question, I am not sure whether there is any trackway or bonebed info on that. There is no need to cite work on sauropods in a paper on much smaller prosauropods. 

I have noticed that the paleowhale people continue to use the term archeocete despite its being paraphyletic. Smart. 

Does the Phylocode actually bar paraphyletic names, such as prosauropods being defined as sauropodomorphs excluding sauropods? 

GSPaul 

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/CACnMvBaEep%3Dg9o3DHJpaMXBTzW%2B2szNiAOeG2PZpSnP9nSVBjQ%40mail.gmail.com.

[Jura]

None of this changes the problem of going from altricial to precocial. As far as I can tell, such a switch has only ever been postulated to have happened in mammals, and it was hypothesized to have occurred due to the longer gestation periods of placentals. Ovipositing animals would seem to face a tougher "challenge" in going from high level of parental investment to low level. It doesn't mean it couldn't happen, but it does require some thought on how it could have happened (e.g., larger bodies able to afford larger yolk sacs per egg). That the authors didn't bother to even pay lip service to this is the issue and it's something that they should have been dinged for during peer review.

Jason

[Tim Williams]

Gregory Paul wrote:

> Quite correct. Unfortunately because of the anti-scientific convention of no longer taxonomically directly recognizing grade as well as
> clade, prosauropods which are radically different from their elephantine sauropod relations are chucked together as sauropodomorphs,

"Prosauropods" and sauropods share an exclusive common ancestry, with the former constituting a series of outgroups to the latter.  

As I understand, the point of "Prosauropoda" is to define this group based on the absence of characters that are found in 'titanic' sauropods.  But many sauropod characters (including those associated with large body size) are also found in various "prosauropod" taxa.  So this typological approach is fraught.

> sort of how humans and Raranimus are all therapsids.

Mammals are therapsids - just as birds are dinosaurs.  I don't see a problem here.

[Gregory Paul]

The  below  is not correct. Prosauropoda is sauropodomorphs that are not in Sauropoda. Read what I say, not what you imagine I say. 

Interesting that no one has said if Prosauropoda is illicit in the Phylocode. Last  time I checked such paraphyletic groups did not seem to be either approved or explicitly disapproved, but  I could be wrong. And if it is not explicitly disapproved, is it automatically approved? 

GSPaul

--
You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.
To view this discussion on the web visit

https://groups.google.com/d/msgid/DinosaurMailingGroup/CA%2BnnY_GWpd-%2BQ-XfpJwu7NX4q4bT%3D8rieYaMXeQVqfXWD_AD4A%40mail.gmail.com

.

[Tim Williams]

Gregory Paul wrote:

> The  below  is not correct. Prosauropoda is sauropodomorphs that are not in Sauropoda.

Same thing.

> Interesting that no one has said if Prosauropoda is illicit in the Phylocode. Last  time I checked such paraphyletic groups did not seem to be
> either approved or explicitly disapproved, but  I could be wrong. And if it is not explicitly disapproved, is it automatically approved?

The PhyloCode only provides rules for applying names to clades, and not to paraphyletic taxa.  So although naming paraphyletic taxa is not formally proscribed, it's not what PhyloCode was set up to do.  That's my 'take' on it.

For example, I doubt the following definition would pass muster under the PhyloCode: euprosauropods = prosauropods with elongated, slender necks that include _Plateosaurus_.  

  

[Gregory Paul]

Many basal and some derived prosauropods were not titanic in adult size -- and may have been able to care for their young. 

Character plus clade names are accepted by the PC. Gauthier explicitly stated that back in 86 or so, and it is in the PC instructions. What can be disputed is the particular practicality of a definition in terms of the precision of the character definition. 

So is a paraphyletic name valid because it is outside the PC? 

--
You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.
To view this discussion on the web visit

https://groups.google.com/d/msgid/DinosaurMailingGroup/CA%2BnnY_FkmtO3%2B21acTvRYxnnK41fTOpHdc4b_TgCtQbzAqz26g%40mail.gmail.com

.

[Mike Taylor]

The PhyloCode has nothing to say about paraphyletic names, because it explicitly wants to govern them. But if you wanted to publish such a name, there's equally nothing in the PhyloCode that could prevent you. And your name/definition would be accepted or not by the community, just as in practice is also true of names established under the PhyloCode (or even the ICZN).

-- Mike.

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/1577570919.1623907.1725368273093%40mail.yahoo.com.

[Jerry Harris]

The solution seems simple enough: you can always use "prosauropod" in quotation marks to denote that you're acknowledging that it's a paraphyletic group. This would probably require having to define somewhere in any paper in which you use the term thusly as "all sauropodomorphs that aren't sauropods" or some such, just for maximal clarity. "Prosauropod" (in quotes) is a terrific shorthand for "all sauropodomorphs that aren't sauropods" and it makes communication simpler and more concise. I do not see a point to forcing Prosauropoda into existence as if it should be treated identically to a monophyletic group, or naming paraphyletic groups at all. Certainly we can acknowledge that Prosauropoda was, historically, considered a valid grouping in the Linnaean system, but that it's gone the way of Pachydermata and Thecodontia and all the other groupings that were para- or polyphyletic, but I do not understand the point of equalizing names for mono-, para-, and polyphyletic groups...am I missing something?

[Mike Taylor]

I guess we've been around this a few times now. I have never seen the point on a religious prohibition on naming groups of other than the officially approved topology, but I'm prepared to accept by this point that I'm in a minority.

But this:

> "Prosauropod" (in quotes) is a terrific shorthand for "all sauropodomorphs that aren't sauropods" and it makes communication simpler and more concise. I do not see a point to [...] naming paraphyletic groups at all.

Speaks for itself. "I so not see a point to a terrific shorthand that makes communication simpler and more concise".

¯\_(ツ)_/¯

-- Mike.

[Iain Reid]

"Prosauropod" is a useful shorthand for communication, and I as well don't see any issue with being used as a vernacular name as Jerry is suggesting. Issues come up if we try to formalize Prosauropoda Huene, 1920 in any sort of official manner. The PhyloCode does not administrate grades, and the ICZN does not administrate ranked nomenclature above the family-group, so Prosauropoda is not under the umbrella of any code. It shouldn't be defined and registered with the PhyloCode as it is not under that code's umbrella. And trying to come up with a formal definition for it also goes against the "simpler and more concise" communication.

What definition would we use? Prosauropoda as used by Huene was for all non-sauropod sauropodomorphs. Over time that paraphyly was recognized and authors began to shrink the encompassed taxa to the point where at the end (Upchurch et al., 2007) Prosauropoda was a monophyletic clade of sauropodomorphs that did not include early sauropodomorphs (Saturnalia, Thecodontosauurus, Mussaurus, Efraasia) or derived taxa we now have as sauropodiforms (Jingshanosaurus, melanorosaurids). Would we ignore the last decades of use of Prosauropoda as a group that only encompasses plateosaurids, massospondylids and anchisaurids? Especially with the flip flopping definitions of Sauropoda, what definition would a formal Prosauropoda get? Saturnaliids/guaibasaurids/unaysaurids were never under the umbrella, thecodontosaurids and anchisaurids were but not always, and melanorosaurids have been both sauropods and prosauropods.

It just seems cleaner and clearer to allow for prosauropod to be a vernacular term, whether within quotations or not, instead of trying to create a definition for a group with no applicable code for that definition to follow. The closest standards we have to follow are those of Linnaean taxonomy, and I don't see much desire to revert back to that structure of organization. Naming (defining) paraphyletic groups for use in taxonomy is a different beast from naming (coming up with informal names) paraphyletic groups for use in communication.

--
You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/CACnMvBaXxHi7K_qwhiUDi6Sgp5_YnAjBS-EeVhtD47ZsWb4GQg%40mail.gmail.com.

[Mike Taylor]

On Tue, 3 Sept 2024 at 16:59, Iain Reid <iains...@gmail.com> wrote:

"Prosauropod" is a useful shorthand for communication, and I as well don't see any issue with being used as a vernacular name as Jerry is suggesting. Issues come up if we try to formalize Prosauropoda Huene, 1920 in any sort of official manner. The PhyloCode does not administrate grades, and the ICZN does not administrate ranked nomenclature above the family-group, so Prosauropoda is not under the umbrella of any code.

That doesn't make a lick of difference. The PhyloCode only came into effect a couple of years ago: people had been happily making and using phylogenetic definitions without it for well over three decades. A code is Nice To Have, but far from essential.

 

It shouldn't be defined and registered with the PhyloCode as it is not under that code's umbrella.

Not "shouldn't", but "can't".

 

And trying to come up with a formal definition for it also goes against the "simpler and more concise" communication.

What definition would we use?

Obviously, Sauropodomorpha without Sauropoda. No other definition has ever been proposed. The fact that dozens of papers all redundantly define "prosauropod" in exactly this way should make it pretty obvious what's always meant by the term.

Anyway, I've said all I have to say on this subject, not just in the present thread but in several predecessors. So I'm going to let this lie now, and those who disagree with me are welcome to the final words.

-- Mike.

[Skye McDavid]

One additional wrinkle in the case of Prosauropoda specifically is that it has occasionally been treated as a clade and was given a phylogenetic definition (Plateosaurus > Saltasaurus; Sereno 1998). Perhaps the most notable use of Prosauropoda as a clade is in the 2004 edition of The Dinosauria. This definition predates the PhyloCode, but if one were to strictly use phylogenetic definitions that predate the PhyloCode, then Prosauropoda would be roughly equivalent to Plateosauridae, and much more restricted than its traditional usage for non-sauropod sauropodomorphs. 

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/CAFR_--bK2TfMZz75vVgB1c1PaSQdBX-yUrSxX1TcCUz-Qu-GUA%40mail.gmail.com.

--

Skye McDavid

(she/her)

https://www.skyemcdavid.com/

This message was sent at a time that is convenient for me. I do not expect you to reply outside of your normal working hours.

[Stephen Poropat]

Maybe we could use non-clade / grade names with an indicative punctuation mark afterwards or before to indicate that they are not monophyletic, in the same way that a dagger mark is used (at least sometimes) to indicate that a clade is extinct?

Dr Stephen F. Poropat

Research Fellow

Western Australian Organic and Isotope Geochemistry Centre

School of Earth and Planetary Sciences

Curtin University

Bentley, Western Australia

Australia 6102

https://stephenporopat.weebly.com/

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/CABrjrNHDgUd9YDxwFa5OVhycqDPuaE-rJ%3DM_3kk8iiq6Lm050Q%40mail.gmail.com.

[Gregory Paul]

I decline to use quotation marks, that accomodating to not using formal paraphyletic groups when I object to that attitude. And I am certainly not doing that in my upcoming field guide to Prosauropods and Sauropods -- like should the title be "Prosauropods" and Sauropods (will not use Sauropodomorphs in the title because that nerd techno jargon would literally kill sales). In the text it's prosauropods without marks. Same as I used rhamphorhynchoids in the pterosaur guide rather than the snooze inducing nonpterodactyloids or basal pterodactyloids. I try not to be cruel to my readers. I explain the nonsense accepted situation early in the text and define the terms and move on. 

Like I said the early fossil whale people use archeocete. So why not prosauropod, iguanodont, thecodont, pelycosaur?

Now there are situations that one has to use basal so and so or non. For example it is now apparent that only a minority of small tyrannosaur remains from the Hell Creek, Lance et al. are juvenile Tyrannosaurus. The rest are not even tyrannosaurids, being big armed basal eutyrannosaurs such as species of Nanotyrannus and Stygivenator and maybe more. But the and the Appalachian nontyrannosaurid eutyrannosaurs are too poorly preserved or not yet described to sort out if their interrelationships, so I chuck them together in an informal baso-eutyrannosaurs. When Bloody Mary and Jane are described that might change, or maybe not because the eastern US material is so incomplete. In the guides I use informal terms like baso-hadrosaurs, baso-tetranurans, baso-prosauropods when similar situations arise, their informal status indicated by the dash.  

Eoraptor and Buriolestes are much more like Plateosaurus and Melanorosaurus than those are to Giraffatitan, Brontosaurus and Nigersaurus which are radically different, so prosauropods can accomodate all the nonsauropod sauropodomorphs which is a dreadful name for nonexperts to put up with. 

GSPaul

https://groups.google.com/d/msgid/DinosaurMailingGroup/e05c4887-ded2-4197-880e-adfb4465f449n%40googlegroups.com

.

[Tim Williams]

Gregory Paul wrote:

> I decline to use quotation marks, that accomodating to not using formal paraphyletic groups when I object to that attitude. And I am certainly
> not doing that in my upcoming field guide to Prosauropods and Sauropods -- like should the title be "Prosauropods" and Sauropods

I've seen certain informal names for paraphyletic grades put in quotation marks in the technical literature - such as "condylarth" and "pelycosaur".  But this isn't always the case - such as archaeocete (as mentioned).  The separate question is should a formal name be used for a paraphyletic grade (such as Prosauropoda).  (AFAIK the recent papers that use archaeocete do not use a formal group Archaeoceti.)  

Personally, I think it's fine to keep certain grade-based words going  for convenience (prosauropod, archaeocete, pelycosaur etc) on a case-by-case basis.  But I'm against having paraphyletic grades as formal groups, because it gets us down the rabbit hole of Linnaean typological thinking - and before long we're arguing over whether Dinosauria should go back to being a separate group to Aves.  And then we'll bring back Pisces for all the fishes - after all, doesn't a lungfish look more like a salmon than it does a human?  (That last question was rhetorical and sarcastic - I'm quite content with tetrapods being put inside Sarcopterygii.)

> (will not use Sauropodomorphs in the title because that nerd techno jargon would literally kill sales).

If baso-eutyrannosaur is not 'nerd techno jargon', then I don't know what is.

> Like I said the early fossil whale people use archeocete. So why not prosauropod, iguanodont, thecodont, pelycosaur?

The other names might have some utility as vernacular/informal terms, but I'd prefer not to see the name thecodont ever again.  The name has too much baggage.  In the past Thecodontia was used as a wastebasket group, often to disguise the fact that the relationships among the members were not resolved.  

> But the and the Appalachian nontyrannosaurid eutyrannosaurs are too poorly preserved or not yet described to sort out if their
> interrelationships, so I chuck them together in an informal baso-eutyrannosaurs.

This must be an eye-of-the-beholder thing, but the term baso-eutyrannosaur looks awkward to me.  You have to explain what a eutyrannosaur is, and also what is meant by the baso- prefix.  But I find nothing wrong with sauropodomorph.  The name Sauropodomorpha has existed for nearly 100 years, and been in circulation as a clade name since the 1990s.  

I find the barrage of new taxonomic names in these dinosaur 'Field Guides' to be confusing: paxceratopsians, baso-eutyrannosaurs, euprosauropods, airfoilans, avebrevicaudans, and so on.  The reader has to grapple with a whole new taxonomic nomenclature.  Further, many of these Field-Guide-specific names draw upon concepts that are not widely accepted in the technical literature.  By contrast, what I liked about the old Field Guide by David Lambert is that it was a good-faith effort to summarize the current 'state of play' in dinosaur paleontology.

[Gregory Paul]

Some of the concerns appear excessive. Aves are going to remain in Dinosauria as Chiroptera are going to remain in Mammalia. And some discussions on the issue might be useful. For example should Therapsida include mammals in part because doing so leaves a whole bunch of distinctive Permo-Triassic protomammals without the simple tag that for eons all knew and loved them by? Why do we have to refer to almost all dinosaurs that are not birds in relation to that minor relatively uniform subgroup with two words as nonavian dinosaurs? Why not terradinosaurs? Think about it. 

In my submitted and don't hold your breath on seeing it soon if ever paper on the TT-zone tyrannosaurs great and little the proper PC term for the long armed graciles that are not Tyrannosaurus juveniles is nontyrannosaurid eutyrannosaurus (because tyrannosaurids probably all have the dinky arms). Using the eye and mouthful endlessly was ridiculous so near the beginning I say I will be calling them baso-eutyrannosaurs which works much better. I have no plans to use it in a pop book (it is not in the guides). 

What is wrong with baso-tyrannosauroids in the guides? There is this amorphous collection of tyrannosauroids whose intrarelationships are very obscure. What else is the group to be called? Same for baso-tetanurans. 

Thecodontia can be technically defined to include all the forms that used to be in it, Archosauriformes except Avemetarsalia. That includes all the old thecodonts including chasmatosuchids, proterosuchids, erythrosuchids, euparkerids, proterochampsids, ornithosuchids, phtyosaurs, and pseudosuchians that share the thecodont grade low slung, short necked, lizard-croc like basal archosaur form, with crocs being the living thecodonts like birds are the living dinosaurs. Way cool. Saying that crocs are living pseudosuchians is less satisfactory because that is just one clade of the greater basal archosaur group it was a part of and still represents. 

I hate sauropodomorph. Lousy boring name. Ick. Gag me with a spoon. Only jargonpiles can like it. We can blame Marsh for saddling the clade of super dinosaurs with a dull name about their feet that is not even close to accurate. Should have been something about how huge they were. Something to do with titanic, colossal. Is that too much to ask? A book title with sauropodmorphs in it is death, Princeton U Press is glad I am avoiding it. As I did not using theropod in my books on those. Beast foot, what the hell does that mean Othniel? Have been trying to replace it with the much more pertinent avepod which neotheropod is a subset of.  

GSPaul

--
You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.
To view this discussion on the web visit

https://groups.google.com/d/msgid/DinosaurMailingGroup/CA%2BnnY_FvwY%2BB9jQzV4BBLM-jGy-wy8sFABYZsCQWkAaD1eBRqg%40mail.gmail.com

.

[Tim Williams]

Gregory Paul wrote:

> Some of the concerns appear excessive. Aves are going to remain in Dinosauria as Chiroptera are going to remain in Mammalia. And some
> discussions on the issue might be useful. For example should Therapsida include mammals in part because doing so leaves a whole bunch of
> distinctive Permo-Triassic protomammals without the simple tag that for eons all knew and loved them by? Why do we have to refer to almost all
> dinosaurs that are not birds in relation to that minor relatively uniform subgroup with two words as nonavian dinosaurs? Why not
> terradinosaurs? Think about it.

I think it's a bad idea.

For this "minor relatively uniform subgroup" (i.e. birds) - is _Archaeopteryx_ a member of this subgroup?  Or is _Archaeopteryx_ a 'terradinosaur'?  

What about _Microraptor_?  Or _Deinonychus_?  _Anchiornis_?  _Oviraptor_?  _Ambopteryx_?  _Mononykus_?  Avians or 'terradinosaurs'?

That's the trouble with Linnaean typology - where to draw the line?  These distinctive "forms" of yours weren't cut from whole cloth.  This problem doesn't come up with clades.  For clades, all taxa are united by common descent, not by perceived (and often entirely subjective) similarities in "form".  

[Ethan Schoales]

Tim, if someone casually called an animal you listed in your second paragraph a “bird”, would you stop them?

--

You received this message because you are subscribed to the Google Groups "Dinosaur Mailing Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to DinosaurMailingG...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/DinosaurMailingGroup/CA%2BnnY_HbhF6ves-MxbZxcGS3VTGkotBp05xpSOwcx8P58HL2Fg%40mail.gmail.com.

[Tim Williams]

Ethan Schoales <ethan.s...@gmail.com> wrote:

> Tim, if someone casually called an animal you listed in your second paragraph a “bird”, would you stop them?

Good question.  Bird is a vernacular term, so I don't think I'd care much either way.  If pressed, I'd probably prefer that the term 'bird' be limited to members of the clade that includes _Archaeopteryx_ and anything more crownward (Avialae or Ornithes).  But that's just based on historical usage of the term "bird", nothing typological.

However, I might baulk at calling these 'avian' if the term 'avian' was used to denote a member of crown-group Aves.

[Tim Williams]

Gregory Paul wrote:

> Thecodontia can be technically defined to include all the forms that used to be in it, Archosauriformes except Avemetarsalia. That includes
> all the old thecodonts including chasmatosuchids, proterosuchids, erythrosuchids, euparkerids, proterochampsids, ornithosuchids, phtyosaurs,
> and pseudosuchians that share the thecodont grade low slung, short necked, lizard-croc like basal archosaur form, with crocs being the living
> thecodonts like birds are the living dinosaurs. Way cool.

_Effigia_ and _Saltoposuchus_ both say: "Way NOT cool!"