Abstract: Disclosed herein are biologically inspired, either manual or electronic, portable fluid expression system to be used for, but not limited to, breast milk expression from nursing women and other milk expression from any species of mammal. The fluid expression systems can be configured to mimic the anatomy of a suckling infant and the biomechanics and fluid dynamics associated with this behavior. The fluid expression system can be used by nursing mothers to express breast milk efficiently, painlessly, and discreetly. The systems can include a single, contiguous flexible structure designed to resemble the lips and oropharyngeal cavity of a newborn infant of the mammalian species of interest. Rigid external housings or stiffening structures can be used to mimic the bony anatomy of the infant or mammalian species of interest.