Among the vertebrate lineages with different hearing frequency ranges. humans lie between the low-frequency hearing (1 kHz) of fish and amphibians and the high-frequency hearing (100 kHz) of bats and dolphins. Little is known about the mechanism underlying such a striking difference in the limits of hearing frequency. Prestin. https://parisnaturalfoodes.shop/product-category/f-c-l-non-gelatin/