Bite force quotient

Bite force quotient (BFQ) is a numerical value commonly used to represent the bite force of an animal, while also taking factors like the animal's size into account.

The BFQ is calculated as the regression of the quotient of an animal's bite force in newtons divided by its body mass in kilograms.[1] The BFQ was first applied by Wroe et al. (2005) in a paper comparing bite forces, body masses and prey size in a range of living and extinct mammalian carnivores, later expanded on by Christiansen & Wroe (2007).[2] Results showed that predators that take relatively large prey have large bite forces for their size, i.e., once adjusted for allometry. The authors predicted bite forces using beam theory, based on the directly proportional relationship between muscle cross-sectional area and the maximal force muscles can generate. Because body mass is proportional to volume the relationship between bite force and body mass is allometric. All else being equal, it would be expected to follow a 2/3 power rule. Consequently, small species would be expected to bite harder for their size than large species if a simple ratio of bite force to body mass is used, resulting in bias. Applying the BFQ normalizes the data allowing for fair comparison between species of different sizes in much the same way as an encephalization quotient normalizes data for brain size to body mass comparisons. It is a means for comparison, not an indicator of absolute bite force. In short, if an animal or species has a high BFQ this indicates that it bites hard for its size after controlling for allometry.

Hite et al.,[3] who include data from the widest range of living mammals of any bite force regression to date, produce from their regression the BFQ equation:

Or equivalently

where BF = Bite Force (N), and BM = Body Mass (g)

Carnivore BFQs

[edit]
Animal BFQ
Aardwolf 77
European badger 109
Asian black bear 44
American black bear 64
Brown bear 78
Domestic cat 67
Cheetah 119
Cougar 108
Coyote 88
Dhole 132
Dingo 125
African wild dog 138
Domestic dog 114
Singing dog 100
Arctic fox 97
Cape genet 48
Gray fox 80
Red fox 92
Gray wolf 136
Brown hyena 123
Spotted hyena 124
Jaguar 134
Jaguarundi 75
Leopard 98
Clouded leopard 137
Lion 128.1
Northern olingo 162
Sand cat 137
Sun bear 160
Least weasel 164
Spotted-tailed quoll 179
Tasmanian devil 181
Tiger 139
Thylacine 166

Table sources (unless otherwise stated):[1][4][2][5]

Sex Differences for BFQ in Canids

[edit]

In a 2020 paper, the results of an estimation of the BFQ of various canid species separated by sex were published.[6] Below there is a table with the BFQ averaged from the BFQ for each espécimen of each sex and for each species. BFQ coming from a single specimen for each sex in a given species will be marked with an asterisk.

Common Name Scientific Name Male BFQ Female BFQ
Short-eared dog Atelocynus microtis 120.25 144.65
Senegalese wolf Canis lupaster anthus 140.66 126.24
*Golden jackal *Canis aureus *113.98 *113.25
Coyote Canis latrans 132.65 131.88
Grey wolf Canis lupus 130.59 141.06
Dingo Canis lupus dingo 133.67 127.57
New Guinea singing dog Canis lupus hallstromi 130.26 107.31
*Red wolf *Canis rufus *182.41 *124.33
Ethiopian wolf Canis simensis 144.27 158.21
Crab-eating fox Cerdocyon thous 118.24 116.41
Maned wolf Chrysocyon brachyurus 131.59 112.87
Dhole Cuon alpinus 148.80 147.85
Side-striped jackal Lupullela adusta 111.21 107.21
Black-backed jackal Lupullela mesomelas 126.95 115.11
Culpeo Lycalopex culpaeus 128.62 120.07
*Darwin's fox *Lycalopex fulvipes *154.63 *140.60
South American gray fox Lycalopex griseus 135.27 124.87
Pampas fox Lycalopex gymnocercus 127.1 116.76
Sechuran fox Lycalopex sechurae 128.84 138.14
Hoary fox Lycalopex vetulus 123.09 122.13
African wild dog Lycaon pictus 144.71 146.08
Common raccoon dog Nyctereutes procyonoides 136.49 134.94
Bat-eared fox Otocyon megalotis 107.14 126.26
Bush dog Speothos venaticus 160.28 154.63
Gray fox Urocyon cinereoargenteus 146.30 121.51
Island fox Urocyon littoralis 109.27 108.22
Bengal fox Vulpes bengalensis 128.47 139.10
Cape fox Vulpes chama 96.98 87.21
Artic fox Vulpes lagopus 120.59 115.34
Kit fox Vulpes macrotis 109.77 110.99
Pale fox Vulpes pallida 89.47 98.21
Rüppell's fox Vulpes ruepellii 135.31 121.97
Swift fox Vulpes velox 122.57 120.38
Red fox Vulpes vulpes 116.25 118.97
Fennec fox Vulpes zerda 113 129.62

References

[edit]
  1. ^ a b Wroe S, McHenry C, Thomason J (March 2005). "Bite club: comparative bite force in big biting mammals and the prediction of predatory behaviour in fossil taxa". Proc. Biol. Sci. 272 (1563): 619–25. doi:10.1098/rspb.2004.2986. PMC 1564077. PMID 15817436.
  2. ^ a b Per Christiansen; Stephen Wroe (2007). "Bite Forces and Evolutionary Adaptations to Feeding Ecology in Carnivores" (PDF). Ecology. 88 (2): 347–358. doi:10.1890/0012-9658(2007)88[347:bfaeat]2.0.co;2. PMID 17479753.
  3. ^ Hite, Natalee J.; Germain, Cody; Cain, Blake W.; Sheldon, Mason; Perala, Sai Saketh Nandan; Sarko, Diana K. (2019). "The Better to Eat You With: Bite Force in the Naked Mole-Rat (Heterocephalus glaber) Is Stronger Than Predicted Based on Body Size". Frontiers in Integrative Neuroscience. 13: 70. doi:10.3389/fnint.2019.00070. ISSN 1662-5145. PMC 6904307. PMID 31866840.
  4. ^ Fish That Fake Orgasms: And Other Zoological Curiosities, Matt Walker, Macmillan, 2007, pp. 98-9, ISBN 978-0-312-37116-6 (retrieved 15 August 2010 from Google Books)
  5. ^ Campbell, C. "Biology: Behavior - Diet". The Thylacine Museum. Archived from the original on 2017-06-21. Retrieved 16 December 2020.
  6. ^ Magalhães, Arthur Ramalho; Damasceno, Elis Marina; Astúa, Diego (2020). "Bite force sexual dimorphism in Canidae (Mammalia: Carnivora): relations between diet, sociality and bite force intersexual differences". Hystrix, the Italian Journal of Mammalogy. 31 (2): 99–104. doi:10.4404/hystrix-00332-2020. ISSN 0394-1914.