Equine herpesvirus 4 infected domestic horses associated with Sintashta spoke-wheeled chariots around 4,000 years ago.

"data availability the data are available on ncbi under biosample: samea9533417"

"to ascertain the best-fitting clock prior between a strict clock and a relaxed lognormal clock we performed a model selection test using the nested sampling (ns) approach ( ; ) available through the ns package (v 1 1 0) and based upon established guidelines from the dedicated taming the beast ( ) tutorial ( https://taming-the-beast org/tutorials/ns-tutorial/ns-tutorial pdf ) and the github nested sampling faq ( https://github com/beast2-dev/nested-sampling/wiki/faq )."

"Conflict of interest: None declared."

"Funding This project has received funding from the Centre National de la Recherche Scientifique (CNRS) and University Paul Sabatier (AnimalFarm IRP), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement 681605-PEGASUS) and the European Research Council (ERC) through the Horsepower Synergy grant (Agreement no. 101071707). O.L. and K.M. were supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreements no. 895107 and no. 897931, respectively."