Mass extinction: the return to life

How quickly does nature recover after a mass extinction? Until now, it was assumed that it would take around 10 million years to rebuild complex ecosystems. In other words, to rebuild an entire food chain, from plants to predators, molluscs and fish. But an international team of researchers has just demonstrated that after just 1 million years, this chain, also known as "trophic", had already been re-established.