Size and scale topic

I read more carefully the paper,  Mr. Larramendi essay is about the superiority of volumetric method on the allometric one to estimate body mass and height at shoulders of big animals like proboscidians. I don't know if he won the game. I even think that allometry is still used in breeding to know the optimal size of meat breed animals (these are people as serious as scientists given the economic stakes)

About Extant proboscidians he wrote:
"The complete fusion of long-bone epiphyses in today’s elephants occurs late among males, around the age of 40, and at around the age of 25 in females
(Roth 1984; Haynes 1991; Lister 1999; Larramendi 2014). It is thus expected that elephants attain their maximum stature by the end of the long-bone epiphyseal fusion. Both sexes, however, seem to continue growing throughout their lives (see Laws 1966; Lindeque and van Jaarsveld 1993). For this paper, fully-grown individuals are considered to be those who have completed their long-bone epiphyseal fusion."

For this paper, fully-grown individuals are considered to be those who have completed their long-bone epiphyseal fusion... For this paper.

Maybe I miss something with my poor english but if "both sexes, however, seem to continue growing throughout their lives" it means that individuals who have completed their long-bone epiphyseal fusion aren't necessarily fully-grown, it even means the opposite, they will continue to grow.

I don't know how this article is received by the scientific world but, although a neophyte, I find things in it that bother me.
Why use Homo sapiens in the size demonstration? There is a stark difference between the two species (I'm not talking about ears and trunks), humans stop growing when they reach adulthood, elephants don't.

Of course, the fact that taller than average individuals see their limb size increase more than their body size is true enough for our species and it seems to me to be true for elephants as well.
A young or average individual will look more compact than a tall individual.
Why am I talking about this? Because, in my opinion, the global form of a model must be taken into account when we want to choose where to affect it in the different possible scales.
For example, for the Mojo, I would tend to affect it in the largest scale.
I don't have the time right now but I'll take a few photos to illustrate my point.

Even the measures presented in the studies cause me problems. The table is large, full of small dots but it concerns "only" 264 females and 245 bulls in different populations. If the proportion of taller individuals is as described, the sample studied is a bit small and these individuals could have completely escaped the investigators.

As for the fact that much taller than average individuals are rare, I can totally agree, there are very few billionaires on earth but they do exist.

Kikimalou wrote:

I don't know how this article is received by the scientific world but, although a neophyte, I find things in it that bother me.
Why use Homo sapiens in the size demonstration? There is a stark difference between the two species (I'm not talking about ears and trunks), humans stop growing when they reach adulthood, elephants don't.

Mainly because there isn't much materian on bigger-than-average specimens, and Homo sapiens has lots of data. About allometry, is more than one this is trying to allometrically scale species of which we have lots of live specimens, etc - a complete different one is extimating extinct species of which we don't have a complete skeleton or, even if we have it, no idea on how its life adaptations impacted its skeleton ie. an animal having strong limbs, with thicker bones, is not alwas due to its greater weight compared to a more slender limbed one, they might have some differencies in locomotion, the thicker limbed one might have digged more, etc.

One thing I missed in the Larramendi (2016) article was this. Talking about the Angolan giant, he also says:
“The projected line from the highest point of the scapula of this individual to the base of the extended forefoot, whilst lying on its side, was measured at 417 cm, again indicating a shoulder height of about 396 cm.”
This is much more convincing than estimating shoulder height based on foot circumference.

Unfortunately, I don’t have access to the references that Larramendi mentions. The original reference is probably Ward et al. (1975) Rowland Ward’s Records of Big Game. I am always a bit sceptical about hunting records, as hunters are known to exaggerate their achievements. With such an extreme outlier that is so different from any other data points, one might also wonder whether there was a measurement error. The elephant was measured as a carcass, which raises the possibility that something happened to it before it was measured. Nevertheless, it is possible that the Angolan elephant was indeed very large.

Kikimalou wrote:

Even the measures presented in the studies cause me problems. The table is large, full of small dots but it concerns "only" 264 females and 245 bulls in different populations. If the proportion of taller individuals is as described, the sample studied is a bit small and these individuals could have completely escaped the investigators.
As for the fact that much taller than average individuals are rare, I can totally agree, there are very few billionaires on earth but they do exist.

Yes, I accept that. However, for an article on animal sizes, the sample size in Shrader et al. (2006) is very good and we also have 10 other studies mentioned in Della Rocca (2007). What is most striking is that the data points in Shrader et al.’s figure all clutter around the mean, whereas a 4 m tall elephant would be an extreme outlier. You’d normally expect at least a few elephants between 3.5 and 4 m in one of the many studies. It doesn’t make it impossible that a 4 m elephant existed, but it makes me suspicious.

Regardless of the finer points, I think we agree that 4 m elephants are truly exceptional. For most collections, such large elephants are irrelevant because we would like to have models that are representative. Humans can be 2.5 m tall, but we wouldn’t normally use a 2.5 tall human in a scale collection, and it is the same for a 4 m tall elephant.

More relevant is what the average size of African elephants is. Larramendi says 260 cm for females and 320 cm in good conditions. When we look at Fig. 6 in Della Rocca (2007), presented in my previous post, then we see that 260 and 320 cm are more like the average maximum size across studies. Similarly, in Shrader et al. (2006), 260 and 320 cm are about the average maximum size across populations. The Shrader et al. (2006) study is very useful because it also shows the mean shoulder height across several populations. The mean is about 234 cm for adult females and 282 cm for males.

What annoys me is that many websites suggest that the average African bush elephant is much taller. For example, in their first paragraph on the African bush elephant, Wikipedia says that they can be up to 3.96 m. While that is possibly true, it would be a bit odd to mention as the first characteristic of homo sapiens that they can be up to 2.8 m. Further on, they say that on average, females are 2.6 m and males are 3.2 m. As we have just seen, that is not their average height. Animal Diversity web says that females are 2.2-2.6 m and males are 3.2-4 m. While that is roughly correct for females (I’d say 2-2.6 m), males over 3.2 m aren't very common.

Kikimalou wrote:

It would be interesting to know how the animals in all these graphs were measured, are there any doubts there too?  

The elephants in Shrader et al. (2006) and Della Rocca (2007) were measured using photogrammetry. Della Rocca demonstrated that this is an accurate way of measuring elephants. Other studies measured elephants in different ways. For example, Lindeque and van Jaarsveld (1993) measured shoulder heights of “laterally recumbent elephants”. This is one of their graphs showing the male elephants:
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Larramendi argues that measuring recumbent elephants overestimates standing shoulder height by about 5%, and Lindeque and Van Jaarsveld indeed pointed out that their elephants were larger than in other studies. Nevertheless, they did not find any elephants over 3.5 m (mean for adult males is probably around 3 m). The findings across studies and populations are quite consistent, so I trust them much more than the measurement of a single elephant reported in a hunting record book.

Finally, let’s come back to the elephant that caused all the trouble:
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Measured in a straight line between callipers, my Mojo elephant is 10.6 cm at the shoulder. Assuming that male African elephants are normally 230-350 cm (Shrader et al., 2006), its scale is 1/22 – 1/33. That is the objective part. More subjectively, one might say that Mojo made the shoulders look a bit strange; they seem unnaturally high compared to the rest of the body, so it may be better to think of it as an elephant that is about 10 cm tall (1/23 – 1/35 scale). Even more subjectively, the Mojo looks like a fairly young adult to me because it lacks bulk and its tusks are relatively small. Based on this, I’d say it should probably be slightly smaller than the average size for a bull, so I’d say about 280 cm. In my opinion, the most appropriate scale for the Mojo is therefore 1/26 (assuming 10.6 cm) – 1/28 (assuming 10 cm) scale. I am happy to use it in my 1/32 scale collection, but I try to keep in mind that the Mojo looks quite atypical for a large bull.

Lindeque & Van Jaarsveld (2003)

I agree that the Mojo looks like a fairly young adult but it has tall legs what is supposed for a large adult. Though, the sculpt is fairly narrow. The CollectA model looks an older specimen.
Photogrammetry is the technic we use to calculate the size of a model from a picture using a Lego block as reference.

Kikimalou wrote:

Well I don't agree, we don't collect human figures but animal toys and, again, that changes everything. Do we want to show an individual of average size, minimum size, maximum size or exceptional? It's just a matter of intention. It depends on what you want to show of the animal.
We don't think the same way maybe because you collect exclusively at 1/32 and I display a large part of my collection at different scales.
When you measure a toy it is to check that it is compatible, in one way or another, with your jungle. When I measure a toy, it's to know which possible levels of my jungle it can live on. Then I have to think about which one suits it best.
And even for your collection Roger, if you really followed this reasoning, there are many animals that you should remove from it, starting with the Britains lioness and her sisters.

It's true, it depends on our intention. And I am a bit uncomfortable with my lionesses. My displays aren't fixed. Right now, I have a display with the intention to teach me how small lions can be, so I am displaying the Bandai Africa and Play Visions lionesses with the Mojo Mini lion. They are very small compared to the Hausser Elastolin and Marolin tigers in the same display!

Kikimalou wrote:

Subjectively I think the Mojo is a big bull because it lacks bulk and his legs are longer than those of the Papo angry one by example.
So what says Asier Larramendi about this ?

Not sure what Larramendi says about it. I think it's quite subjective, so if you think it's a very large bull, then it is fine as 1/30 or even 1/35. The main thing is that we know what we are doing. It looks to me as if the Bullyland bull (small version) represents an older and larger elephant. Would you say it represents a smaller individual? The shoulder heights of the Mojo and Bullyland are the same.
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Kikimalou wrote:

Roger, you have a fabulous 1/32 collection but I can show you some 1/22 and 1/25 African animals compared with the Mojo elephant, you will tell me if it's fine for you or if it is better in a 1/32 collection.

If you don't mind taking a photo, I'd enjoy seeing it. When I showed my elephant collection in the 1/32 topic, I mentioned that it misses models that are intermediate in size between the young elephants and the large older elephants. I'd quite like to have some models that are around 2.50 m or even smaller so that my view of elephant sizes becomes less distorted. Models in this size do exist, but the problem is that they usually have large tusks, which suggests that they represent a larger elephant. The Mojo elephant may therefore look a little bit odd with 1/22 or 1/25 scale animals. The Papo with crooked trunk may look better.

Ah, I am so sorry, what did I do? Instead of replying to Christophe's post, I somehow edited it. I didn't know I could do that. Is it possible to revert to Christophe's original post?

Kikimalou wrote:

Well I don't agree, we don't collect human figures but animal toys and, again, that changes everything. Do we want to show an individual of average size, minimum size, maximum size or exceptional? It's just a matter of intention. It depends on what you want to show of the animal.
We don't think the same way maybe because you collect exclusively at 1/32 and I display a large part of my collection at different scales.
When you measure a toy it is to check that it is compatible, in one way or another, with your jungle. When I measure a toy, it's to know which possible levels of my jungle it can live on. Then I have to think about which one suits it best.
And even for your collection Roger, if you really followed this reasoning, there are many animals that you should remove from it, starting with the Britains lioness and her sisters.

It's true, it depends on our intention. And I am a bit uncomfortable with my lionesses. My displays aren't fixed. Right now, I have a display with the intention to teach me how small lions can be, so I am displaying the Bandai Africa and Play Visions lionesses with the Mojo Mini lion. They are very small compared to the Hausser Elastolin and Marolin tigers in the same display!

Kikimalou wrote:

Subjectively I think the Mojo is a big bull because it lacks bulk and his legs are longer than those of the Papo angry one by example.
So what says Asier Larramendi about this ?

Not sure what Larramendi says about it. I think it's quite subjective, so if you think it's a very large bull, then it is fine as 1/30 or even 1/35. The main thing is that we know what we are doing. It looks to me as if the Bullyland bull (small version) represents an older and larger elephant. Would you say it represents a smaller individual? The shoulder heights of the Mojo and Bullyland are the same.
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Kikimalou wrote:

Roger, you have a fabulous 1/32 collection but I can show you some 1/22 and 1/25 African animals compared with the Mojo elephant, you will tell me if it's fine for you or if it is better in a 1/32 collection.

If you don't mind taking a photo, I'd enjoy seeing it. When I showed my elephant collection in the 1/32 topic, I mentioned that it misses models that are intermediate in size between the young elephants and the large older elephants. I'd quite like to have some models that are around 2.50 m or even smaller so that my view of elephant sizes becomes less distorted. Models in this size do exist, but the problem is that they usually have large tusks, which suggests that they represent a larger elephant. The Mojo elephant may therefore look a little bit odd with 1/22 or 1/25 scale animals. The Papo with crooked trunk may look better.

Leyster wrote:

Kikimalou wrote:

I don't know how this article is received by the scientific world but, although a neophyte, I find things in it that bother me.
Why use Homo sapiens in the size demonstration? There is a stark difference between the two species (I'm not talking about ears and trunks), humans stop growing when they reach adulthood, elephants don't.

Mainly because there isn't much materian on bigger-than-average specimens, and Homo sapiens has lots of data. About allometry, is more than one this is trying to allometrically scale species of which we have lots of live specimens, etc - a complete different one is extimating extinct species of which we don't have a complete skeleton or, even if we have it, no idea on how its life adaptations impacted its skeleton ie. an animal having strong limbs, with thicker bones, is not alwas due to its greater weight compared to a more slender limbed one, they might have some differencies in locomotion, the thicker limbed one might have digged more, etc.

Yes I understood. What I mean is that it reminds me the story of the guy who is looking for his glasses under a lamp post when he lost them somewhere else, at least under the lamp post there is light, it's easier for seek...  

rogerpgvg wrote:

Ah, I am so sorry, what did I do? Instead of replying to Christophe's post, I somehow edited it. I didn't know I could do that. Is it possible to revert to Christophe's original post?

Kikimalou wrote:

Well I don't agree, we don't collect human figures but animal toys and, again, that changes everything. Do we want to show an individual of average size, minimum size, maximum size or exceptional? It's just a matter of intention. It depends on what you want to show of the animal.
We don't think the same way maybe because you collect exclusively at 1/32 and I display a large part of my collection at different scales.
When you measure a toy it is to check that it is compatible, in one way or another, with your jungle. When I measure a toy, it's to know which possible levels of my jungle it can live on. Then I have to think about which one suits it best.
And even for your collection Roger, if you really followed this reasoning, there are many animals that you should remove from it, starting with the Britains lioness and her sisters.

It's true, it depends on our intention. And I am a bit uncomfortable with my lionesses. My displays aren't fixed. Right now, I have a display with the intention to teach me how small lions can be, so I am displaying the Bandai Africa and Play Visions lionesses with the Mojo Mini lion. They are very small compared to the Hausser Elastolin and Marolin tigers in the same display!

Kikimalou wrote:

Subjectively I think the Mojo is a big bull because it lacks bulk and his legs are longer than those of the Papo angry one by example.
So what says Asier Larramendi about this ?

Not sure what Larramendi says about it. I think it's quite subjective, so if you think it's a very large bull, then it is fine as 1/30 or even 1/35. The main thing is that we know what we are doing. It looks to me as if the Bullyland bull (small version) represents an older and larger elephant. Would you say it represents a smaller individual? The shoulder heights of the Mojo and Bullyland are the same.
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Kikimalou wrote:

Roger, you have a fabulous 1/32 collection but I can show you some 1/22 and 1/25 African animals compared with the Mojo elephant, you will tell me if it's fine for you or if it is better in a 1/32 collection.

If you don't mind taking a photo, I'd enjoy seeing it. When I showed my elephant collection in the 1/32 topic, I mentioned that it misses models that are intermediate in size between the young elephants and the large older elephants. I'd quite like to have some models that are around 2.50 m or even smaller so that my view of elephant sizes becomes less distorted. Models in this size do exist, but the problem is that they usually have large tusks, which suggests that they represent a larger elephant. The Mojo elephant may therefore look a little bit odd with 1/22 or 1/25 scale animals. The Papo with crooked trunk may look better.

Roger you are a very dangerous man
But the most dangerous one is probably the Portuguese croc who gaves you the moderator tools for this section.

No I can't go back in time and fix the error. Don't worry, I did the same thing to Rogerio years ago. Now I am very careful.

About Lion and Lioness, the Bandai lioness lives a very good life with the Kaiyodo Wild rush Lion on my 1/35 floor.

Since you erased my post   , you also erased what Asier Larramendi wrote :

"Mature elephants attain greater body mass than sub-adult individuals of the same shoulder height (see Kurt and Kumarasinghe 1998), and in African elephants over 30 years of age the height in- creases much less than the weight (Hanks 1972). Therefore, proboscideans tend to become stockier as they mature (there can be exceptions to this rule depending on nutritional con- ditions and other factors). Does this mean that exceptionally tall bulls are proportionally heavier? Or, at least, relatively as heavy as fully grown average-sized specimens? Probably not. It is known that in Namibia, where exceptionally tall elephants survive, they have relatively longer legs (Wood 1982), indicating a negative body mass allometry in unusu- ally tall elephants; they are relatively less heavy compared to the shoulder height as they have longer legs, and therefore relatively shorter and narrower bodies. Therefore, a strong negative allometry is also expected for oversized elephants. Gould (1966) also observed an intraspecific mandible size decrease vs. body length in Lucanus mearesi, in specimens above average. It is also known that larger animals have a general tendency toward shorter torso relative to the width and head length vs. body length relationships, which almost always show negative allometry due to the relatively de- creasing brain size (Gould 1966). These same results can be observed in very tall humans, where a relatively long arm and leg length vs. torso length is a rule, as is a relatively small head size. This is due to the decreasing brain weight/ body size relation."

For now I agree with him

So about Mojo, Bullyland and others, what are my two cents ?

I don't own the "little Bullyland" and the big one left me, so no pictures sorry.
For me, yes, it represents a smaller elephant, the proportions of the legs compared to the body, the length of this one look more classic. The Mojo has longer legs and a proportionately less elongated body quite typical of what Asier Larramendi says above.
As the two toys have the same size at the shoulders, from my point of view, there is something weird and I would not present the two elephants at the same scale.
The only weak point of the Mojo from this point of view is that its head is a little too big.
As for the tusks, well, apart from the female Papo and the Eikoh, they're still very (too much?) big, so that's not what I watch the most, too brand dependent.

So, is the Mojo a young bull or a tall one ? Again I am not denying my own subjectivity, but look at these two photos, the first of a "young elephant" and the second of a "big bull". When I layer the Mojo with the young, the legs are much longer on the toy, the proportions are closer to those of the "big bull" to me.

look also at this pic, you can see one of those famous "big elephants of Namibia" that Larramendi talks about. Please look at the legs.
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And now some models that you know well. There are three bulls and a female

Mojo and Eikoh, two males, the first is bigger but the Japanese looks very serious. They may be able to live together in the same savannah as a reasonably sized elephant and a big guy but that doesn't satisfy me and I prefer to scale the Eikoh up.
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Mojo and Papo, two males, the first is always bigger but the Papo is more "virile". At the same time, given his size, Mr. Mojo has nothing to demonstrate. For me they can coexist in the same savannah like a serious bull and a taller guy.
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Mojo and Papo, Mr. and Mrs. I find them very well matched, in full dimorphism as it should be.
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on 1/22, is the Papo with crooked trunk may look better ? Again , I had it but I let it go along time ago.  To answer that question, from my point of view, no. No Majors elephants can be comfortable at 1/22, they are too small and their proportions would be a bit strange to represent a very young elephant, it is not only the height at the shoulders to take into account.
The only ones that could do the job on this scale is perhaps the old Bullyland and absolutely the Lineol IV.

First of all you should take a look at these two photos of elephants accompanied by zebras: A big one and a smaller one.

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And now here are the two photos that I had already presented. I find him very suitable for 1/30 but he can play the big guys from Namibia at 1/35.

1/30
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1/35
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At 1/25 now, if someone considers him a young male, it can do the job provided we name him "Long legs Johnny"
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At 1/22, for me it's nonsense. He is trumpetting for his mom because the others make fun of his big teeth  
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And now the same with his majesty Lineol IV

1/22
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1/25
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Sorry again for editing your post and for rectifying the mess I created; yes, it is dangerous to give me too many privileges. I mistakenly used the "edit" button instead of the "quote" button.

Thanks a lot for these beautiful photos, it's great to see these comparisons. I find it difficult to match the elephant models with real elephants. The models are kind of idealised elephants, kind of too beautiful to be entirely realistic. I can see that the Mojo has some features of the tall Namibian elephant, especially the long legs. And indeed, none of the elephant models look like smaller, young adults, so they aren't appropriate for 1/22 scale. It would be nice if companies made young, smaller adults. I like the Mojo best in 1/30 scale, though it is possible that that's because it is closest to the 1/32 scale that I am used to seeing on my shelves.

So I'm the dangerous one.
I love those pictures, I also feel more confortable seeing the elephant with the 1:30 scale animals but I don't even dare to discuss and mine is with the 1:35 prehistoric ones so regardless of the best scale to put him, I'm so happy we have now so beautiful pvc African elephants like the Mojö Fun and CollectA ones. Now I just hope CollectA releases an Asian elephant bull at the same level, as we discussed before, the current figure is spectacularly detailed but the porportions are defintely bad.

rogerpgvg wrote:

Sorry again for editing your post and for rectifying the mess I created; yes, it is dangerous to give me too many privileges. I mistakenly used the "edit" button instead of the "quote" button.

Thanks a lot for these beautiful photos, it's great to see these comparisons. I find it difficult to match the elephant models with real elephants. The models are kind of idealised elephants, kind of too beautiful to be entirely realistic. I can see that the Mojo has some features of the tall Namibian elephant, especially the long legs. And indeed, none of the elephant models look like smaller, young adults, so they aren't appropriate for 1/22 scale. It would be nice if companies made young, smaller adults. I like the Mojo best in 1/30 scale, though it is possible that that's because it is closest to the 1/32 scale that I am used to seeing on my shelves.

Yes, we must keep in mind that what we measure are toys, sculptures, interpretations. Each author has put his talent and his point of view as well. I find that the five figurines presented here are excellent and "realistic" in their own way, they all show us a facet of the animal that we like or not according to our own impressions, our own interpretations.
Some like Schleich because the work is well finished and they are full of detail, I don't like them at all because their lack of consistency in proportions is unbearable for toys of this order. Makes sense from a guy who spends his time, tape measure in hand, making scale comparisons.
Large tusks are for me both a choice of companies that must sell their products to children, they must be attractive and safe.
This is also why brands produce Asian elephants with too big tusks and they don't produce "young adult" elephants, there is too much economical risk I guess.
In general, one finds acceptable tusks only in the productions of the 20th century or among the Japanese as on the Eikoh.

Roger wrote:

So I'm the dangerous one.
I love those pictures, I also feel more confortable seeing the elephant with the 1:30 scale animals but I don't even dare to discuss and mine is with the 1:35 prehistoric ones so regardless of the best scale to put him, I'm so happy we have now so beautiful pvc African elephants like the Mojö Fun and CollectA ones. Now I just hope CollectA releases an Asian elephant bull at the same level, as we discussed before, the current figure is spectacularly detailed but the porportions are defintely bad.

Yes dangerous Croc

YesI would be happy if a new Great Asian elephant would come soon
About the Mojo and Papo cow I shown above, here is a pic that sums up my thoughts. Even the higher shoulders are there
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Always enjoy these wonderful comparison photos!

Thanks Taylor

Does anyone know the size of these Epoch wolves?
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I haven't seen these before either... curious to know more about them. Are they part of a fairytale/fable set? Little Red Ridinghood or...?

Haven't seen before either but nice looking wolves!

Christophe and I had a discussion about the size of Chinese sturgeons in his [You must be registered and logged in to see this link.] It gets quite detailed, so it may be more appropriate to talk about it here.

Many websites mention 5 metres as the maximum total length of Chinese sturgeons, probably copying this information from Wikipedia, which says that they are 2-5 metres. The 5 m maximum length appears to be highly questionable. It is interesting that the maximum size of large animals is often based on dubious sources.

Let's have a look at what research articles report. Wang et al. (2012) measured 27 adult Chinese sturgeons and their total length was 245-368 cm, Yang et al. (2006) measured 40 with 246-360 cm TL, Zhu et al. (2002) measured 20 with 298-370 cm TL, Wei et al. (1997) measured 475 with 189-389 cm TL and Hui et al. (2006) measured 783 adults with 200-400 cm TL. Wei et al. show a useful graph with the length distribution:

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Of course, this doesn't prove that 5 m sturgeons don't exist. In general, it is very difficult to prove that something doesn't exist because it is always possible that we didn't search well enough (think of cryptids). However, taking these studies together, the number of measured individuals is very large relative to the population size. For example, Zhang et al. (2014) estimated that the number of spawning Chinese sturgeons (including both females and males) ranged between only 71 and 369 individuals in the years 2004-2008. It is very rare to have so many measurements relative to the size of the population. 5 m is well outside the range that the scientific articles report, so it seems improbable.

Chinese researchers who work with sturgeons (e.g., Zhu et al., 2002, He et al., 2009, Wei et al., 2011) usually mention 400 cm as the maximum size. They refer to an article by Chang and Cao (1999) in Chinese, which in turn refers to another article in Chinese. My AI translator doesn't do a good job, but it corresponds to the maximum observed by Hui et al. (2006). I haven't seen 500 cm in these articles.

The burden of proof is on websites that claim that Chinese sturgeons can reach 5 m. If they make extraordinary claims, they should also present extraordinary evidence. Although there are lots of websites mentioning 5 m, I haven't found any that give the original source of this information. We have no way of verifying it. Given how often animal size information is wrong (especially for large species), I am very sceptical.

Let's look in more detail at the Wikipedia references. Wikipedia refers to a web page by the Chinese Ministry of Culture and to a status report by NOAA Fisheries. Both indeed mention 2-5 m. The Chinese Ministry of Culture does not give any references. NOAA Fisheries refers to the website Pondlife which mentions a 5 m maximum length. Pondlife does not provide a specific reference for this, but it lists some general links. One is to the Encyclopedia of Life (EOL), which lists three individuals measuring 39, 130 and 346 cm. Another is to the Food and Agriculture Organisation (FAO) of the United Nations, which mentions 389 cm as the maximum length (without giving a reference, but this probably comes from Wei et al., 1997). A third link is to Fishbase, which says 346 cm. A fourth is to the World Register of Marine Species (WORMS). This website mentions 39 and 130 cm (with excellent references ). The final link is to the Integrated Taxonomic Information System (ITIS), which does not give any size information. Where is the 5 metres?

Yes you're certainly right, I think my sturgeon will leave the 1/50 stage to join the 1/35 stage for a size of 350cm, it will allow him to rub shoulders with a certain Britains Ltd Asian elephant.