Copepods are known to be the primary consumers of diatoms in the water column and initiate the production of PUA upon grazing.  The consumption of PUA-producing diatoms by copepods has been shown to diminish their reproductive success. Specifically, female copepods that consume diatoms spawn eggs with low viabilities and offspring with high teratogenesis rates. The compounds mainly act by preventing cell division and promoting apoptosis in copepod embryos, though the mechanism behind this is still poorly understood.