EFFECTS OF GLYPHOSATE ON ANTI-PREDATOR MORPHOLOGY IN DAPHNIA PULEX

Abstract

Glyphosate use has rapidly increased over the past several years. It is a broad-spectrum herbicide that destroys weeds and other broadleaf plants. Glyphosate is thought to be a target-specific herbicide that only affects plants. It has been tested on non-target organisms but has not been examined for its effects on anti-predator morphology in cladocerans. The purpose of this experiment was to examine glyphosate effects on Daphnia pulex. I tested three environmentally relevant concentrations of glyphosate in the presence or absence of predatory kairomones to determine its effects on neck teeth induction, number of spines, and carapace growth. Glyphosate significantly decreased organism growth showing that it does have an effect on juvenile D. pulex development. Any changes to anti-predator morphology among D. pulex could make them more vulnerable to predation and result in subsequent changes to freshwater aquatic food webs.