They Were Unable To Survive
Homo heidelbergensis appears to have been more clever than its ancestors. Members, for example, used cutting-edge equipment and developed their hunting skills. Individuals may have worked together to bring down larger creatures, which suggests a kind of social cohesion. Homo heidelbergensis, despite its many advantages, was unable to survive.
Without A Trace
But you should know that Homo heidelbergensis did not vanish without a trace. Quite the contrary, in fact. Middle Pleistocene-era species began to branch apart from this common forefather some 390,000 years ago. In the end, these branches would lead to the emergence of modern humans.