Premise: Aluminium . Despite its prevalence in the environment , no known form of life uses aluminium salts metabolically , but aluminium is well tolerated by plants and animals . Delphinine is a toxic diterpenoid alkaloid found in plants from the Delphinium ( larkspur ) and Atragene ( a clematis ) genera , both in the family Ranunculaceae .
Hypothesis: Aluminium is highly poisonous to plants.
Label: CONTRADICTION