Crossing evolutionary paths: New research finds different hominin species coexisted SalonMuddy footprints suggest 2 species of early humans were neighbors in Kenya 1.5 million years ago The Associated PressContemporary hominin locomotor diversity Science1.5 million-year-old footprints reveal our Homo erectus ancestors lived with a 2nd proto-human species Livescience.comFootprints Suggest Different Human Relatives Lived Alongside One Another The New York Times