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ABSTRACT The Sunyaev–Zel’dolvich (SZ) effect is expected to be instrumental in measuring velocities of distant clusters in near future telescope surveys. We simplify the calculation of peculiar velocities of galaxy clusters using deep learning frameworks trained on numerical simulations to avoid the independent estimation of the optical depth. Images of distorted photon backgrounds are generated for idealized observations using one of the largest cosmological hydrodynamical simulations, the Magneticum simulations. The model is tested to determine its ability of estimating peculiar velocities from future kinetic SZ observations under different noise conditions. The deep learning algorithm displays robustness in estimating peculiar velocities from kinetic SZ effect by an improvement in accuracy of about 17 per cent compared to the analytical approach. 

Neuroptera (lacewings) and allied orders Megaloptera (dobsonflies, alderflies) and Raphidioptera (snakeflies) are predatory insects and together make up the clade Neuropterida. The higher‐level relationships within Neuropterida have historically been widely disputed with multiple competing hypotheses. Moreover, the evolution of important biological innovations among various Neuropterida families, such as the origin, timing and direction of transitions between aquatic and terrestrial habitats of larvae, remains poorly understood. To investigate the origin and diversification of lacewings and their allies, we undertook phylogenetic analyses of mitochondrial genomes of all families of Neuropterida using Bayesian inference, maximum likelihood and maximum parsimony methods. We present a robust, fully resolved phylogeny and divergence time estimation for Neuropterida with strong statistical support for almost all nodes. Mitochondrial sequence data are typified by significant compositional heterogeneity across lineages, and parsimony and models assuming homogeneous rates did not recover Neuroptera as monophyletic. Only a model accounting for compositional heterogeneity (i.e.CAT‐GTR) recovered all orders of Neuropterida as monophyletic. Significant findings of the mitogenomic phylogeny include recovering Raphidioptera as sister to Megaloptera plus Neuroptera. The sister family of all other lacewings are the dusty‐wings (Coniopterygidae), rather than Nevrorthidae. Nevrorthidae are instead returned to their traditional position as the sister group of the spongilla‐flies (Sisyridae) and closely related to Osmylidae. Our divergence time analysis indicates that the Mesozoic was indeed a ‘golden age’ for lacewings, with most families of Neuropterida diverging during the Triassic and Jurassic and all extant families present by the Early Cretaceous. Based on ancestral character state reconstructions of larval habitat we evaluate competing hypotheses regarding the life style of early neuropteridan larvae as either aquatic or terrestrial.