“…Hence, many scholars have made strenuous efforts, so as to find out the impact of age on evolution. For more details, please see [29,19,12,1,28,23,35,36,30,31,10,34,37,33,32] and the references therein for related works. Unfortunately, most of these equations barely get the existence, boundedness and positivity of the solution for the age-dependent version predation equations.…”