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There is growing concern about sensory pollutants affecting ecological communities. Anthropogenically enhanced oxidants [ozone (O₃) and nitrate radicals (NO₃)] rapidly degrade floral scents, potentially reducing pollinator attraction to flowers. However, the physiological and behavioral impacts on pollinators and plant fitness are unknown. Using a nocturnal flower-moth system, we found that atmospherically relevant concentrations of NO₃eliminate flower visitation by moths, and the reaction of NO₃with a subset of monoterpenes is what reduces the scent’s attractiveness. Global atmospheric models of floral scent oxidation reveal that pollinators in certain urban areas may have a reduced ability to perceive and navigate to flowers. These results illustrate the impact of anthropogenic pollutants on an animal’s olfactory ability and indicate that such pollutants may be critical regulators of global pollination.

The ALICE Collaboration reports measurements of the semi-inclusive distribution of charged-particle jets recoiling from a high transverse momentum (high$p_{\mathrm{T}}$) charged hadron, in$pp$and central Pb-Pb collisions at center-of-mass energy per nucleon–nucleon collision$\sqrt{s_{\mathrm{NN}}}=5.02$TeV. The large uncorrelated background in central Pb-Pb collisions is corrected using a data-driven statistical approach which enables precise measurement of recoil jet distributions over a broad range in$p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$and jet resolution parameter$R$. Recoil jet yields are reported for$R=0.2$, 0.4, and 0.5 in the range$7<p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}<140 \mathrm{GeV}/c$and$\pi /2<\mathrm{\Delta }\phi <\pi$, where$\mathrm{\Delta }\phi$is the azimuthal angular separation between hadron trigger and recoil jet. The low-$p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$reach of the measurement explores unique phase space for studying jet quenching, the interaction of jets with the quark–gluon plasma generated in high-energy nuclear collisions. Comparison of$p_{\mathrm{T},\mathrm{ch}\mathrm{jet}}$distributions from$pp$and central Pb-Pb collisions probes medium-induced jet energy loss and intra-jet broadening, while comparison of their acoplanarity distributions explores in-medium jet scattering and medium response. The measurements are compared to theoretical calculations incorporating jet quenching.