Talk:Dinosaur size

A. Giganteous

Antarctosaurus Giganteous is said to be between 58 & 63 tonnes. Even though the upper estimate is certainly smaller than the upper estimate of other suaropodmorphs, the lower estimate is significantly larger than a few large sauropodmorphs on the list. Wouldn't it be fairer and safer to rank size through lower estimate(s)?PNSMurthy (talk) 01:05, 7 August 2020 (UTC)

Paul (2019)[1] estimated "Antarctosaurus" giganteus to be 45-55 t heavy. Also, doesn't Holtz use "elephants" to describe mass instead of providing the actual estimate? Kiwi Rex (talk) 12:33, 23 August 2020 (UTC)

True, but it's still an estimate @Kiwi Rex:.PNSMurthy (talk) 00:53, 25 August 2020 (UTC)

It's a comparison, not an estimate. It's supposed to give an idea of how big it is compared to a modern animal, but we can't know exactly how much the "elephants" in "A". giganteus' mass weigh because the idea is exactly to not provide a number. Kiwi Rex (talk) 03:16, 25 August 2020 (UTC)

We need to sort this out

Hi fellow Wikipedians,

We need to sort this out. How are we measuring the dinosaurs in the list? Lowest estimate or highest estimate? Most recent estimate. Many dinosaurs have ranges of sizes. I honestly think we shouldn't do this, but rank sauropods based on the most recent estimate (unless it is obviously inaccurate - like Ultrasauros).

What do you guys think?

PNSMurthy (talk) 07:44, 25 August 2020 (UTC)

I think we should redo all lists or even get rid of them. Many of those species were more or less the same size. It's very misleading to say X is bigger than Y just because one specimen of X is 10 cm longer than a certain specimen of Y. If we keep the lists, I think we should do something similar to this, and maybe add notes to explain certain estimates (i.e. Molina-Pérez & Larramendi disagree with Paul about the "Mamenchisaurus" sinocanadorum fossil indicating a ~35 m long animal, and the note could explain their argument). Kiwi Rex (talk) 16:41, 25 August 2020 (UTC)

Indeed. I believe we should give precedence to the most recent estimate, and should not give a range of widely differing estimates. By the way; in your sandbox, you have produced an unreasonably small size for Futlongkosaurus.PNSMurthy (talk) 23:04, 25 August 2020 (UTC)

Number lists are honestly rather doomed to be misleading no matter what we do, because they present a strict hierarchy, as opposed to the more ambiguous reality of size estimations. The Dinosaur Facts and Figures books are not reliable sources. Also, I don't understand how 29t is "unreasonably small" for Futalognkosaurus, going by Paul (2019). --Slate Weasel ⟨T - C - S⟩ 23:28, 25 August 2020 (UTC)

It's been suggested in the past that we should just WP:BLOWITUP and I'm inclined to bring that back to the table. Lusotitan (Talk | Contributions) 04:28, 26 August 2020 (UTC)

@State Weasel:, scaling down from Puertosaurus, I gained 41 tonnes. And, like Dreadnoughtus, many estimates give higher sizes. Honestly, I think its shrinkwrapped.PNSMurthy (talk) 04:31, 26 August 2020 (UTC)

@Lusotitan: Okay suggestion, but I disagree. I have a mind to sort through the list and only keep 1 estimate (favorably the latest one).PNSMurthy (talk) 04:31, 26 August 2020 (UTC)

I think the list format is too flawed to ever work, hence why this article never has. Dinosaur size estimation is too uncertain for a list to be reliable or substantive. It feels more like the kind of dick measuring contest you'd find on Carnivora forum than something of any encyclopedic value. The article would be best entirely abandoned and just redirected to dinosaur or shifted in focus to be about how dinosaur size is estimated and the biomechanics behind that size (along with some more limited text-based discussion of the largest and smallest dinosaurs over the years). Lusotitan (Talk | Contributions) 07:10, 26 August 2020 (UTC)

Removing the lists and devoting the article to how dinosaur size is measured, biomechanical implications, and history of scaling is actually an interesting idea... Anyways, why would one scale a dinosaur known from 4 vertebrae to get a mass estimate for a significantly more complete one? If anything, the opposite should be done. Also, the supermassive Dreadnoughtus estimates have been deemed inaccurate by Bates et. al. (2015), who found a mass of 22-38t, comparable to the results published by Paul. But then again, this is not the place for WP:OR, we cannot claim that Paul (2019) is unreasonable based on WP:OR. As for lists, keeping only the latest estimate is problematic in and of itself, as different studies will reconstruct radically different flesh profiles or use entirely different methods to determine body size, and use different taxa. --Slate Weasel ⟨T - C - S⟩ 12:18, 26 August 2020 (UTC)

Putting the most recent study may or may not be good. For example, if a less recent study is well-supported, and then a more recent study is published but only few studies support its conclusions, I will still go for the well-supported study, even if it's less recent. JurassicClassic767 (talk | contribs) 14:31, 26 August 2020 (UTC)

@Lusotitan: This article is relatively well know and popular. What will happen if it disappears one fine day? Even though WP isn't generally considered reliable, its still public, and, if publicly visible. We aren't the only viewers of the page. Again, what will the public do?PNSMurthy (talk) 23:10, 26 August 2020 (UTC)

I don't fully understand your worries - it seems like the main options the article will be overhauled, in which case the public can read the new article, or the article gets redirected to a section in Dinosaur, where the public can read that section. --Slate Weasel ⟨T - C - S⟩ 12:20, 27 August 2020 (UTC)

Agreed, the contents won't "disappear", they'll perhaps just change or will be redirected to another page. JurassicClassic767 (talk | contribs) 14:57, 27 August 2020 (UTC)

That's perfect. Let's all start practising what we preach now okay? Lets get to work.PNSMurthy (talk) 23:08, 27 August 2020 (UTC)

Regarding the inclusion of estimates from that book, my intention was initially to have something to create the table with, and only later put more estimates from better sources. I chose that one to start with just because it's one of the few compilations of multiple estimates. It wasn't my intention to actually put those numbers in an article - I also think they are fishy. Kiwi Rex (talk) 00:35, 29 August 2020 (UTC)

By the way, this is also why I think the theropod version is better - it lists the numbers for length and mass together instead of dividing by source, but still mentions exactly who estimated what number. (Unreliable sources here too; this is just a model). Kiwi Rex (talk) 00:40, 29 August 2020 (UTC)

Another Source

Found a blog post that shows a massive sauropod (at least 80 tonnes as far as I can tell). If you think the source is still unreliable, the blog cites a source that also describes the sauropod in question (albeit briefly). Can this be catalogued - that is, if we do not rework the whole list?PNSMurthy (talk) 09:39, 28 August 2020 (UTC)

I realise have forgotten to link the post, here is the link:https://thesauropodomorphlair.wordpress.com/2020/06/04/the-candeleros-monster/.PNSMurthy (talk) 09:43, 28 August 2020 (UTC)

This, again, does not qualify as a reliable source. With blogs, stick with those published by the experts in the field (i.e. SV-POW!). Rib scaling is honestly quite a terrible method to get a reliable estimates. This post assumes that "proximal half" means exactly one half of the rib AND that this rib belongs to a lognkosaur in order to reach the conclusions. The error margin for such estimates is immense. --Slate Weasel ⟨T - C - S⟩ 12:13, 28 August 2020 (UTC)

State Weasel, I also mentioned that this blog post cited the article in which it got the rib from. The same source also hints at this dinosaur being similar (or even a sister taxon), to Argentinasaurus, which is a Longkosaur.PNSMurthy (talk) 00:27, 29 August 2020 (UTC)

The source provides no overall size estimate though, other than that it comes from a "gigantic" animal. Additionally, the source only hints about a relation to Argentinosaurus, stating "Further studies (Calvo in prep.) will establish if it has some relationships with the largest known sauropod, Argentinosaurus." This leaves things a little open-ended, as such a study seems to be lacking, and it is only stated that it could be related to Argentinosaurus. Titanosaur phylogeny has changed radically in the last 21 years, so that throws further uncertainty on things. --Slate Weasel ⟨T - C - S⟩

Admittedly, I seem to be unable to argue on such shaky ground:)PNSMurthy (talk) 00:04, 30 August 2020 (UTC)

Name of MPM-PV-39

What is the name of that dinosaur?PNSMurthy (talk) 07:34, 3 September 2020 (UTC)

It is a femur from the Cerro Fortalezo Formation (then known as the Pari Aike Formation) described briefly by Lacovara et. al. (2004) in an abstract. It is indeed massive, measuring about 2.2 m long and bearing a circumference of 99 cm, and apparently also quite robust. Here's the citation:

• Lacovara, Kenneth; Harris, Jerald; Lammana, Matthew; Novas, Fernando; Martínez, Rubén; Ambrosio, Alfredo (2004). "An enormous sauropod from the Maastrichtian Pari Aike Formation of southernmost Patagonia". Journal of Vertebrate Paleontology. 24 (3): A81.

This specimen has no name, and if I had to guess, it probably belongs to either Puertasaurus or Dreadnoughtus (neither of which were named in 2004). --Slate Weasel ⟨T - C - S⟩ 12:55, 3 September 2020 (UTC)

@State Weasel: Try Notocolossus? Dreadnoughtus is far too skinny and small. Whilst, we barely have anything on Puertosaurus. I'd either bet Notocolossus or Patagotitan. Both are MUCH more complete than Puertosaurus, and MUCH larger than Dreadnoughtus.PNSMurthy (talk) 01:03, 4 September 2020 (UTC)

I don't fully understand. Dreadnoughtus has some of the most robust limb bones of any non-saltasaurid titanosaur, hardly "far too skinny," not to mention that it probably exceeds the similarly long lognkosaur Futalognkosaurus in mass, not to mention that the only known specimens are immature. Notocolossus is from the Plottier Formation, and Patagotitan isn't even from the same epoch. Granted, as WP:OR bars us from assigning this to any species in particular for the article, but we already have two named giant titanosaurs from the Cerro Fortaleza Formation. --Slate Weasel ⟨T - C - S⟩ 12:09, 4 September 2020 (UTC)

Dreadnoughtus, my friend, has weight estimates ranging from 22.8 to 59.1 tonnes! And its certainly somewhere in the middle (probably 35 tonnes - if I had to guess). We also know that the largest specimen's length if only around 23 or 24 meters long - which is still a little shorter than F. Dukei. As for the fact that these specimens are juveniles, there are no estimates on the specimens' age, so that's fully of the park for now.

Now, returning to the topic, Dreadnoughtus is probably way smaller than this unnamed dinosaur - at least, until we know how old the largest specimen was. As for Puertosaurus, we do not have any limb material assigned to that genus. Puertosaurus is way to fragmentary to be assumed as the genus in which this new dinosaur is to be placed!

And, okay, P. Mayorum is not in the same epoch. My bad. But, Notocolossus is our best bet since is in a similar size range to this new and undescribed dinosaur. Furthermore, even if these two options are incorrect, I would like to know if this dinosaur is even a titanosaur, or some somphospondyl.PNSMurthy (talk) 00:55, 5 September 2020 (UTC)

I think that we both may have gotten a bit to far into this, as it doesn't really impact the article at all - although I must say that I don't understand why you argue that Notocolossus is a better assignment, since it doesn't preserve a femur either and isn't from the same formation. The femur of Dreadnoughtus is 1.91m long in the larger specimen, but even knowing which stage of growth it was at (which we do - it was mentioned in the appendicular osteology paper) won't allow us to reliably estimate adult size as far as I know. For the moment, though, it's probably best just to think of it as an indeterminate titanosaur until we can get some more info. The abstract does seem to assign the femur to Titanosauria, and it definitely exhibits characteristics of titanosauriformes. On the subject of the article, I'd recommend that we avoid dealing with unnamed and indeterminate taxa, unless there's really good reason not to (i.e. pre-2017 Patagotitan). Also, specimen numbers don't go in italics. --Slate Weasel ⟨T - C - S⟩ 11:44, 5 September 2020 (UTC)

Agreed. We are going far of topic. I only argue for Notocolossus because it is a little more complete than Puertosaurus, and, an adult. By the way, what article estimates the age of Dreadnoughtus? I think it might be of some interest to me.PNSMurthy (talk) 00:17, 6 September 2020 (UTC)

Ullman & Lacovara (2016) provide an estimated age of "subadult" for the Dreadnoughtus holotype, or a "stage 9" individual out of the 13-14 ontogenetic stages of Klein & Sander (2008). --Slate Weasel ⟨T - C - S⟩ 00:40, 6 September 2020 (UTC)

Thank you. Quite young then.PNSMurthy (talk) 00:51, 6 September 2020 (UTC)