In each sensillum type, mutations of the receptors within the same oval all produce the same kind of phenotype, i.e. reduced, novel, or increased responses, to the indicated tastants. Thus in I-a sensilla, deletions of either Gr32a, Gr33a, or Gr66a produce a reduced response to BER, DEN, ESC, LOB, QUI, and SPS; loss of Gr32a or Gr89a produce a novel response to CAF, COU, THE, and TPH; loss of Gr32a but not Gr89a produces novel responses to ARI, SAP, and UMB. See also Figure S2.