Animal bite force

[creature386]

Here you can collect data about published bite force estimates of animals. Not all the ones which I will post will be accurate, but I just want to collect some.

This isn't published, but I still think Grey's summary belongs to such an overview therad:
theworldofanimals.proboards.com/index.cgi?board=animals&action=display&thread=32




animalcreativity.webs.com/Bite%20forces,%20canine%20strength%20and%20skull%20allometry%20in%20carnivores.pdf


With respect to previous estimates of bite force in gigantic
taxa, a bite force of 5300N has been proposed for the
Devonian placoderm fish Dunkleosteus terrelli (Anderson &
Westneat, 2007), and using a reverse engineering approach it
has been calculated that a bite force of 13 400N was
required for a large maxillary tooth of Tyrannosaurus rex
to cause measurable damage to the pelvis of a Triceratops
(Erickson et al., 1996).
www.bio-nica.info/Biblioteca/Wroe2008GreatWhiteSharkBiteForce.pdf


Hartstone-Rose, A., Perry, J., Morrow, C., 2012. Bite Force Estimation and the Fiber Architecture of Felid Masticatory Muscles. The Anatomical Record 295, 1336-1351.

Here some links now:
rsbl.royalsocietypublishing.org/content/8/4/660.full.pdf+html
rspb.royalsocietypublishing.org/content/271/1547/1451.full.pdf
www.newscientist.com/article/dn12712-sabretooth-cat-had-a-surprisingly-delicate-bite.html

Ursus arctos also has shown this, but I don't know the source:
coherent has shown it:
scholar.google.at/scholar?cluster=15750547468032030016&hl=de&as_sdt=0,5

[coherentsheaf]

Jifeng, here is the source: scholar.google.at/scholar?cluster=15750547468032030016&hl=de&as_sdt=0,5

I found this paper to be disturbingly bad in both documentation and its probable underestimation of PCSA, the relevant discussion can be found on carnivora somewhere. The Carcharocles estimates are speculative crap as well.

[LeopJag]

The figures for the cheetah shouldn't be higher than the jaguar's and the cougar's.. *facepalm*

[creature386]

May 8, 2013 2:37:44 GMT 5 coherentsheaf said:

The Carcharocles estimates are speculative crap as well.

I know that the upper estimates were considered as unlikely. Does that also hold true for the others aswell?

[coherentsheaf]

May 8, 2013 15:30:15 GMT 5 creature386 said:

May 8, 2013 2:37:44 GMT 5 coherentsheaf said:

The Carcharocles estimates are speculative crap as well.

I know that the upper estimates were considered as unlikely. Does that also hold true for the others aswell?

I dont know if the upper range is unlikely, it may even have been higher. I just think the method of taking the rather unrelated gws and scaling many orders of magnitude wont work well in general.

[Grey]

I would not consider Wroe's prediction for megalodon as speculative crap, more like grossly indicative data. It gives at best an idea of the magnitude we can expect for megatooth. Of course, the truth was probably quite different given the differences between it and the white shark and the fact we actually definitely don't know its exact body mass.

Why do you think it may even have been higher than the upper range predicted by Wroe ? Don't forget that 180 000 Newtons is based on the highest size estimate by Gottfried. I assume you suggest this because of the teeth much more robust in proportions than in the white shark ?

[theropod]

May 8, 2013 7:11:36 GMT 5 LeopJag said:

The figures for the cheetah shouldn't be higher than the jaguar's and the cougar's.. *facepalm*

A weight figure for those animals would be pretty helpful, otherwise what use is comparing them? That could be a 25kg leopardess and a 60kg cheetah...

[creature386]

I can't tell it you at the moment, because I can't read the paper for some reason.

[coherentsheaf]

May 18, 2013 12:54:40 GMT 5 Grey said:

I would not consider Wroe's prediction for megalodon as speculative crap, more like grossly indicative data. It gives at best an idea of the magnitude we can expect for megatooth. Of course, the truth was probably quite different given the differences between it and the white shark and the fact we actually definitely don't know its exact body mass.

Why do you think it may even have been higher than the upper range predicted by Wroe ? Don't forget that 180 000 Newtons is based on the highest size estimate by Gottfried. I assume you suggest this because of the teeth much more robust in proportions than in the white shark ?

I think the most important factor for uncertainty is that we do not know how gooddry skull estimates are for sharks. In crocodiles and mammals they lead to gigantic underestimates. This why I think it might be an underestimate- however the literature on extant sharks suggest not as much as in the case of tetrapods. The teeth have nothing to do with it. Broad teeth are associated with low bite forces in modern sharks.

[Grey]

I agree with that thought, I had myself suggested that.

I've read Hubbert about the tooth morphology related to bite force, but regardless of these documentations, we know that pretty big whales skeletons dating back Miocene and Pliocene wear very deep gashes, some decapitated (the Bakersifled cetotherid) and some reported broken in half (multiple reported skeletons from the Ica desert in Peru).

Regardless of Hubbert, the limited works and the common knowledge that sharks don't have particularly impressive bites, we can expect that megatooth had in absolute terms at least, a humongous power when biting, especially due to the lateral shaking.

[creature386]

Here is another paper by Wroe:
onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2011.00862.x/abstract
It's from 2011 and deals with the bite force of bears.
He said Agriotherium africanum was a very strong biter, while the modern plar bear is a rather weak one.

[Supercommunist]

[Grey]

Jun 1, 2013 12:55:43 GMT 5 coherentsheaf said:

Jun 1, 2013 9:12:32 GMT 5 Fragillimus335 said:

Lolong is estimated to have a bite force of ~7290lbs of force... that's up in Tyrannosaurus territory. :0 Scary stuff.

The newest paper estimating Tyrannosaurus bite force underestimated croc bite force. Similarly McHenry's PHD thesis predits a bite frce similar t or slightly higher than a crocodile's bite force at similar weight for Sue. The popularly cited numbers for Tyrannosaurus are underestimates, most likely by a factr of about 2-3.

So you suggest that overall, the majority of the predictions of bite force in extinct taxa are most likely to be underestimate, if I follow your reasonning right ?

[coherentsheaf]

Jun 2, 2013 6:54:49 GMT 5 Grey said:

Jun 1, 2013 12:55:43 GMT 5 coherentsheaf said:

The newest paper estimating Tyrannosaurus bite force underestimated croc bite force. Similarly McHenry's PHD thesis predits a bite frce similar t or slightly higher than a crocodile's bite force at similar weight for Sue. The popularly cited numbers for Tyrannosaurus are underestimates, most likely by a factr of about 2-3.

So you suggest that overall, the majority of the predictions of bite force in extinct taxa are most likely to be underestimate, if I follow your reasonning right ?

I think that (at least most) dry skull estimates are underestimates, as muscle corss sectional area tends to be underestimated. To quote McHenry:

The discrepancy between dry skull derived estimates of bite force, and observed values for the same taxa, is especially important. In all cases, observed bite force exceeds the predictions based upon the dry skull method; for example, the Alligator specimen (Figure 7-10) predicted in the present study to have a bite force of 1338 N at the rear bite position (Table 7-7) should have an in vivo bite force of 3900–4500 N according to Erickson et al.’s data. Ellis et al. (2008) recorded a canine bite of 859 N in a 40 kg dog which has a dry skull predicted bite force of 451 N. Individual data points from studies on other taxa, such as the spotted hyaena Crocuta crocuta (Binder and Van Valkenburgh 2000), also point to a much larger in vivo bite force than the value predicted from the dry skull method.


there are other studies with similar results. On carnivora forum Ursus showed a new study for Panthera, where the new estimates were also much larger than those previously predicted.

However soe of the estimates are overestimates. Erickson's 2012 estimate for a 3500kg Deinosuchus likely is, as isometric scaling from extant crocs would predict a considerably lower estimate.

[theropod]

And the multibody-dynamics method produces overestimates for some and tremendous underestimates for others?

what about this:

Predicted bite force in our human and Alligator models
closely match previous values (figure 2a, f ). Our human
bite forces (700–1020 N) overlap experimental values
of 730–749 N [5,6] and lie within estimates in earlier
modelling studies of 678–1080 N [7,8], with variability
across studies attributed to significant variation in
muscle size between individuals and the level of muscle
activation associated with different biting activities
[5–8]. Erickson et al. [13] reported peak forces of
500–765 N and 9000–11 125 N in alligators of equi-
valent size to our models. Peak forces in the initial
biting impact overlap these values (figure 2a, f; juvenile
601–801 N, adult 9800–13 135 N). Sustained bite
Biol. Lett.
force in the juvenile model (202–266 N) overlaps the
higher end values of Porro et al. ([12]; 120–215 N), and
shows even closer agreement (148–209 N) if we use the
lower value for FPUA (250 000 N m22) preferred by
these authors.

Is it really the same as with the dry skull estimates?



In Deinonychus, do you mean the estimate based on toothmarks? I heard of some gigantic figure for T. rex based on toothmarks, so they migutn produce overestimates in general. On the other hand the 2012 study stated the two previous, bite-mark based estimates were significantly lower than theirs.