Summary: The G. Adomian
’s decomposition method (ADM) [J. Math. Anal. Appl. 135, No. 2, 501–544 (1988; Zbl 0671.34053
)] is presented for finding the exact solutions of more general biological population models. A new solution is constructed by power series. The fractional derivatives are described in the M. Caputo
sense [Ann. Univ. Ferrara, Nuova Ser., Sez. VII 41, 73–84 (1995; Zbl 0882.34007
)]. To illustrate the reliability of the method, some examples are provided.