Vertebrates emerged around 500 million years ago from a massive evolutionary upheaval that involved two successive doublings in the amount of DNA in a marine invertebrate. These dramatic events triggered the evolution of a new animal, which became the ancestor of the backboned fishes, birds, reptiles and mammals, including humans.

“Amazingly, what happened so long ago still affects the life and diseases of modern humans,” said Professor Carol MacKintosh, of the College of Life Sciences at the University of Dundee.

The new research, published in the Royal Society journal Open Biology, proposes how these ancient DNA doublings boosted internal communication systems. The result is that cells in our bodies are far better at integrating information than even the smartest smartphones.

Such complexity is needed to coordinate the actions of our elaborate human bodies. The downside is that communication breakdowns cause diabetes, cancer and neurological disorders.

Researchers have been able to compare the human genome to the recently decoded genetic sequence of the invertebrate amphioxus, a tiny creature still found in our seas and which can be regarded as a `distant cousin’ to our species.