sentences:  A review article (Carreck & Ratnieks, 2015) concluded that while laboratory based studies have demonstrated adverse sub-lethal effects of neonicotinoid insecticides on honey bees and bumble bees, these same effects have not been observed in field studies, which is likely due to an overestimation of three key dosage factors (concentration, duration and choice) in many laboratory based studies.In 2017, researchers demonstrated the combined effects of nutritional stress and low doses of common, widely used neonicotinoid pesticides (clothianidin, thiamethoxam) found in nectar and pollen.Their results provided the first demonstration that neonicotinoids and nutrition levels can synergistically interact and cause significant harm to animal survival, showing the complexity of neonicotinoid effects.