So I was looking at the supplementary material of
Therrien et al. (2023). They have equations to calculate the minimum and maximum body mass of prey taken for a mammalian or reptilian predator of a given body mass.
The phylogenetically-corrected generalized least-squares regression for maximum prey body mass for mammalian predators is log max prey mass =
a log predator mass +
b, where
a equals 1.165 and
b equals -0.233.
This study looked at
Gorgosaurus, and estimated an adult specimen to weigh ~2,626 kg. To estimate its maximum prey size, this would mean a formula as follows:
log max prey mass = 1.165*log(2626) – 0.233
log max prey mass = 3.750
max prey mass = 5,623.4 kg
So if we take this equation at face value, an adult
Gorgosaurus weighing ~2.6 tonnes could prey on an animal as massive as an average adult bull African bush elephant (5.2-6.9 tonnes on average). Contemporary megaherbivorous dinosaurs like
Styracosaurus (~4,370 kg) and
Corythosaurus (3,620 kg) are within this prey size range.
The juvenile
Gorgosaurus specimen that had small
Citipes in its gut contents was estimated to weigh 334.4 kg by the authors. If we put its body mass into this equation, we get a maximum prey mass of ~509.33 kg.
HOWEVER...I question the accuracy of at least some of the maximum prey mass figures for extant predators they use. For example, the lion's maximum prey body mass in log(kg) is 2.740, which translates to animals weighing 549.54 kg (the lion's body mass in log(kg) is reported as 2.312, which is 205.12 kg). And how accurate is that? Well...
Clearly even a single lion is capable of taking down animals far larger than about half a metric ton. By contrast, the tiger (reported at 111.94 kg) has a reported maximum prey body mass of 2,722.7 kg. Needless to say, no matter how much of a tiger fan you may be, I think anyone should see the absurdity of a tiger being able to take prey 24 times its own body mass, while a lion nearly twice said tiger's body mass is limited to taking prey only ~2.7 times its own body mass.
As the excerpt from the supplementary material above alludes to, some of their data input for reptilian predator maximum prey body mass is also not quite accurate, namely underestimating the maximum prey mass of some large crocodilians. Similarly, what do they report the Komodo dragon's (reported body mass 47 kg) maximum prey mass as? 1.717, which translates to 52.119 kg (said prey claimed to be a Rusa deer)...
Lol
www.google.com/books/edition/Komodo_Dragons/MqFfBgAAQBAJ?hl=en&gbpv=1&dq=komodo%20dragon%20predation%20water%20buffalo%20auffenberg&pg=PT9&printsec=frontcoverNow, to be fair, I'm not a reptile expert, and I can't speak for the vast majority of the species listed in their supplementary info. However, it's clear that some of the info could use a bit of work. I guess the takeaway here is that, while this equation can be very useful, and maybe it gives some idea as to how big of a prey item a certain predator can take (I don't doubt an adult
Gorgosaurus could take an animal weighing 5.6 tonnes, or a juvenile weighing 334 kg could take an animal weighing half a tonne), maybe it should be refined with more accurate information on extant predator maximum prey size. Maybe some extinct predators will have their maximum prey size underestimated (although, I can't think of many prey items in
Gorgosaurus' ecosystem that were several times its body mass). Maybe some overestimated (especially if it lacks macropredatory adaptations)?
Just some food for thought.