Influential feeding dynamics of sharks and mathematical formulas to estimate the power of biting by morphological data

Document Type: Research Paper


1 MSc student, Biology Department, Ferdowsi University of Mashhad, Mashhad, Iran

2 Professor, Biology department, Ferdowsi University of Mashhad, Mashhad, Iran

3 PhD Candidate, Mechanical Engineering, Ferdowsi University of Mashhad, Iran


The mouths of some bony and cartilaginous fishes are located in the anterior part of their
bodies, with a slight variation in sharks, which have theirs located in the abdominal part. This
variation is evolutionary over time. The force exerted by the jaws of sharks in order to
dismember their prey can be examined from two origins: .The determined force exerted by teeth
and muscles and the force as a result of torque arm through jaw distance. Although sharks apply
less force compared to crocodile, their sharp teeth and mouth position provides much stronger
effect. Moreover, several species are characterized with heavier upper jaw and this enhances the
power. A mouth located in the anterior part of the body would have less force exerted. On the
contrary, human jaw is shorter, which applies much more force. This paper relates the prebranchial
length and power with preying strength. According to this survey, a couple of
predators were considered in terms of their mouth position, as well as different kind of feeding
and ecological characteristics. Morphological data on several sharks were extracted and
evaluated by MATLAB software to prove the following deductive hypothesis. The more the
support distance (prebranchial length) to concentrated force was, the stronger the shark preyed
on animals. The amount of torque had significant relationship with the lever distance and
concentrated force. Besides, several formulas have been recommended to estimate the bite force
and torque based on morphological characteristics.


Main Subjects

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