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(04-29-2022, 09:36 PM)Pckts Wrote: You're not comparing averages of both specimens, you're comparing an average of one specimen to a single individual of another.
On top of that, you're not even comparing the same body weight.
For instance, Adriano who was measured in a straight line and weighed 130kg was 152cm in head and body.
That is 10cm shorter in length than the Sumatran Tiger average and 12kg's heavier.
Crawshaw also measured another in a straight line that was 122kg and it was less than 151cm in length.
So as you can see, Jaguars are going to be shorter in length and shoulder height but they pack more mass. They are the more dense animal overall.
This has nothing to do with cherry picking, these animals are measured and presented. Feel free to present any and all Sumatran Tigers that are comparable. Again it has nothing to do with isometric scaling, you have true numbers right in front of you.
And what does it matter? Averages use outliers and runts, they are just a number we like to use but have nothing to do with the actual cats on an individual basis. But generally speaking, a Jaguar will be shorter in length and shoulder than a Sumatran Tiger but will still be comparable in weight. Obviously exceptions exist for either side, but more often if you take 130kg specimens from either, that's how it's going to play out.
Proportional to what?
Sumatrans generally are longer in body at similar weights.
They are all part of the average, you using a single Llanos jaguar holds as much weight as a single 120kg individual. On average, Pantanal Jaguars are going to be 108kg and shorter in length and shoulder height. Unfortunately Sumatrans body weight averages and measurements are much harder to come by.
But generally speaking using Gautes table, they average 117kg and 162cm in body length. And assuming the longest on his table was the heaviest *which it may not be* it was only 140kg and 177cm long while Joker was 165cm the first capture then 179cm over the curves which really would be around 170cm in a straight line and weighed over 140kgs both times.
Another Sumatran Tiger from a hunting record was 180cm over the curves and weighed 142kgs.
So this paints a pretty clear picture, like what I've been saying. Jaguars generally will weigh more at similar lengths and shorter shoulder heights.
Jaguar shoulder height in the pantanal averages around 26.28 inches while Sumatrans generally are around 30'' at the shoulder *limited data exists though*
Long story short, you can compare both are equal lengths and the Jaguar generally will be a little heavier.
Next I'll see what I can get for skulls
WRONG! Everything you said is completely WRONG. I already made it clear above that I am comparing the AVERAGE Sumatran to the AVERAGE Jaguar.
But you are comparing a BULKIER than average Jaguar to the average Tiger so your comparison is nonsensical in itself.
And don’t you understand isometric scaling, do you? Rather than using a 120kg, bulkier than average Jaguar specimen, I isometrically scaled THE AVERAGE Jaguar to 120kg. Do you understand that?
You obviously are unable to comprehend the concept of isometric scaling so there is no point in arguing further.
Even Bengal Tigers can reach 280kg and American Lions also were often 280kg but American Lion would be LONGER at that weight, does that mean Bengal Tigers are more robust? No!! Not at all because Ngandong Tigers were still longer in length than American Lions.
I’m sorry I don’t mean to be offensive but you don’t seem to able to understand even simple physics.
Okay answer this question. How will you compare the average male Jaguar with an average male BENGAL Tiger in terms of ‘pound for pound’? Jaguars don’t even reach the 210-220kg weight so you tell me how you will make this comparison.
I would recommend you to check out Christiansen and Harris weight estimation studies, that might give you an idea about how isometric scaling works.
There is nothing to debate, you have the actual weights and measurements presented.
And once again, Isometric scaling is used to estimate, it's not exact while you have actual weights and measurements that are exact.
You scaling the average Jaguar which you don't even know what average is, it sounds like to 120kgs is far less valid than using actual 120kg Jaguars.
Your claim about Tigers and Lions makes no sense.
Funny you mention Christiansen, he literally says the same about jaguars compared to other cats.
Quote:Okay answer this question. How will you compare the average male Jaguar with an average male BENGAL Tiger in terms of ‘pound for pound’? Jaguars don’t even reach the 210-220kg weight so you tell me how you will make this comparison.
But this isn't needed, once again we have a Tiger and Jaguar that already exist in comparable weights.
You need to let go of this stance, you have verifiable data shown, it doesn't get more exact than that.
No! A big 220kg HYPOTHETICAL Jaguar would be similar in proportions to a small Jaguar which means its a case of isometric scaling NOT allometric which would only be done when the large animal is completely different in proportions compared to the small animal.
Your comparison is totally pointless because you are comparing a bulkier, extra muscular Jaguar to the average Sumatran Tiger which is not the correct way to make such comparisons.
And it doesn’t matter, I still stand by my initial point. I’m sure the Sumatran tiger still has a stronger bite than those Jaguars but you don’t understand even simple physics.
Now you tell me, how will you compare the Jaguar to a South African Lion in terms of ‘pound for pound’. Answer this question now. You don’t have a Sumatran like Lion, do you? How will you compare these two in pound for pound then.
What are you not understanding here?
Two Jaguars can weigh the same and still have completely different body measurements. Those proportions would be very different depending on the individual.
And what do you want to compare in regards to the Lion and Jaguar?
lb for lb what?
lb for lb bite force. Please compare lb for lb bite force for a Jaguar and a Bengal Tiger. Show me how much bite force will a Jaguar have in comparison to a Bengal Tiger if Jaguars are scaled to the same weight as Bengal Tigers.
Please show me the calculation and steps here while you do it and let’s see what the result comes out to be.
Again there is no way to calculate this with accuracy.
There are morphological differences that contribute to a bite force, then interpreting those differences isn't even universally accepted.
For instance,
-The shape of the mandible.
-The muscle attachment opening for the Masseters and temporalis.
-The shape and size of the Sagital Crest
-Canine bending strength and size
-Gape
and so on
If you want to use a simple equation it should be head size in relation to body size.
But again, you will have some Cats that are longer skulls while others are wider, but in terms of bite strength, the width should play a larger role than the length.
Come on! What are you talking about? We can simply scale the same Jaguar to 200kg by keeping all its body proportions and morphology intact.
It is very simple, the Jaguar will scale by 2 times and the bite force will only increase by around 1.77 times.
What are you talking about? We don’t need to calculate any of that. All of it has already been calculated by that same bite force study so what will you calculate? The force and weight ratio has ALREADY been calculated by that study. All we need to do is scale the weight to 2 times and when that happens the bite force would still be 12% weaker.
We are just talking about a hypothetical pound for pound scenario which means the same Jaguar from that study when scaled to twice the size, it’s bite force will only increase by 1.777 times. This is the simplest possible physics.
And please don’t say that actual animals aren’t used to estimate bite forces and all that.
In the end, the simple thing is that particular study said a 100kg Jaguar bites with 3/4 the force of a 200kg Tiger. Now we are comparing the exact same things pound for pound and in such a case you simply scale the exact same Jaguar morphology to 200kg and then the bite force would still be 12% weaker than the Tiger’s bite force.
It’s as simple as that. That is simple ‘pound for pound’ comparison. In pound for pound comparisons, the muscular cross section (and the force) would only scale with an exponent of 2 while the weight will scale with an exponent of 3. It’s as simple as that.
This will cause the bite force to lag behind and thus the Tiger would still have a stronger bite.
It's literally going in circles with you
The bite force is calculated off an estimated body weight. Added to that, these skulls came from captive cats only " We dissected the masticatory muscles of nine species of felids (Table 1), represented by a total of 28 specimens. All but two of the specimens were from Carolina Tiger Rescue (CTR; formerly the Carnivore Preservation Trust)"
Using a weight of 100kg for this particular Jaguar is meaningless, that's not a real 100kg Jaguar from the Pantanal or a 200kg Tiger from India. Their skull morphology is very different to their wild counterparts.
Also, it's not just "lb for lb"
There are numerous factors going into their scaling
"One alternative is to scale masticatory variables to a functionally meaningful anatomical measurement. Mandible length is often used as a scaling variable because it is a rough proxy for the load arm of an anterior bite (Hylander, 1979; Daegling, 2001; Vinyard et al., 2003; Vinyard and Hanna, 2005). If posterior bites are of greater interest, then the distance between the mandibular condyle and a molar could be used (Taylor et al., 2012). Instead of scaling to these variables, we have explicitly included them in the estimate of BF by measuring different hypothetical load arms at different bite points. This allows us to examine BF as a single variable and consider its scaling in relation to body size.
To sidestep the problems of periodic body mass fluctuations, we also use (e.g., in Perry, 2008; Perry and Hartstone-Rose, 2011; Perry et al., 2011) a cranial geometric mean as a proxy for overall body size. BM, JL and GM all yield very similar (statistically indistinguishable) regression results across all of the taxa that we have studied, though this is especially true for the morphologically homogenous Felidae."
"Our results demonstrate that masticatory muscle masses scale isometrically tending toward positive allometry when regressed against body mass and jaw length. The slope is statistically greater than one for all muscles (except the highly variable medial pterygoid) when regressed against a geometric mean of cranial variables. PCSA, and BF scale with significant positive allometry for all three scaling variables. This significance is driven by the exceptionally high correlations of these variables with all three independent variables in this morphologically conservative lineage. Scaling of FL tends towards negative allometry, but there is great scatter in the data and isometry cannot be ruled out statistically. However, FL is slightly less well-correlated with body size, resulting in higher absolute residuals, suggesting the potential for a dietary signal. Indeed a strong signal suggests a relationship between FL and relative prey size. Thus, in the family Felidae, where food material properties vary little, food geometric properties appear to select for muscle architectural properties. In at least one instance (the jaguar), estimated BF appears to signal food material properties—namely this species is capable of consuming more obdurate foods."
You are making it exceedingly complex even though it’s the simplest possible thing. When we compare the bite force pound for pound, we do it the way I described. That’s it.
But you aren’t able to understand simple physics so I can’t tell you anything else.
Why don’t you simply show your calculation right here? I already did the simple calculation and showed you that the Tiger would still have a 12% stronger bite even at equal weights.
Do you have any calculations of your own? If you do then show me your calculation right here. Show me what the bite force of the Jaguar would be at 200kg bodyweight. But if you don’t have any of that to show then this argument is pointless.
This is the simplest physics but you don’t seem to be able to comprehend this.
It has nothing to do with understanding, you're cutting corners to try and save face. You are disregarding real factors that came into play in determining the bite force.
It's literally providing you the multiple processes used in making that conclusion.
It's using real jaw muscle weights obtained against an estimated body mass on top of that, it's bringing into account bone formation and muscle distribution. All of which would need to be allometrically scaled.
You are simply just using a calculation to say "what if the jaguar was double the size" but it's absolutely clear that's not the only factor used to determine it's biteforce.
On top of that, you have real measurements from comparable animals not in captivity and have been explained the actual differences in their morphology. The fact that you don't seem to acknowledge this or understand it makes the rest this debate pointless.
The strongest bites in the animal kingdom
