Back in the laboratory, they deposited different amounts of Bt and non Bt pollen on leaf-discs and fed each in a single dose to a first instar larva which was observed over the next three days. They found no effect with the Bt-pollen collected from the field, even at the highest dosage. As the laboratory experiments involved feeding a single dose over three days, it gave no information as to the effects on mortality of cumulative doses over the entire life-cycle of the butterfly, such as it may experience in the field. It will be an abuse of science if this report were to be accepted as evidence that Bt-pollen is safe for black swallowtails. References and Notes 1.
Transgenic pollen harms monarch larvae.
Nature 399, 214. 2. Absence of toxicity of Bacillus thuringiensis pollen to black swallowtails under field conditions. PNAS early Ed.