A Bite Force Quotient (BFQ) is a numerical value which is used to represent the bite force of an animal while also taking factors like the animal's size into account. Pure bite force data can be very interesting, but difficult to compare across species; by using a Bite Force Quotient, researchers can compare across species, and consider how and why these animals have different jaw strengths.
Classically, bite force is established by taking a dry jawbone and using it as a lever to determine the failure point of the bone; in other words, the bone is used as a lever until it cracks. The bite force reflects the amount of pressure it took to break the jaw. It is also possible to use live animals to collect data, by getting the animals to bite down on objects which have been equipped with pressure sensors. However, this method is imperfect, because the animal may not bite with full strength.
When a Bite Force Quotient is calculated, researchers take the bite force data and consider it alongside the animal's size, the maximum size of its prey, and the types of prey it consumes. All of this information is plugged into a formula which generates a single number reflecting the bite force with adjustments for external factors. Such data can then be manipulated in a variety of ways to look at the animal world with fresh eyes.
Remarkably, marsupials appear to have some of the highest Bite Force Quotients in the world, along with Clouded Leopards and Tasmanian Devils, thrusting animals like the crocodile right out of the competition. However, a high Bite Force Quotient doesn't necessarily mean that an animal will do the most damage; marsupials like koalas can deal a lot of damage for their body size, for example, but most people would prefer a koala bite to a lion bite, because lions are so much larger and more powerful.
By looking at data from around the world, researchers can learn more about how animals evolved, why some animals have such a high Bite Force Quotient, and why others are comparatively weak. This data can also be collected for extinct animals, if a breakable jawbone can be obtained, potentially providing insight into how and where those animals lived.