Scientists identify genetic building blocks behind human heart's subtle control system

Since the early 1900s, scientists have been wondering how birds and mammals could have developed almost identical conduction systems independently of each other when their common ancestor was a cold-blooded reptile with a sponge-like inner heart that has virtually no conduction bundles.

The studies show that it is simply the spongy inner tissue in the foetal heart that gets stretched out to become a fine network of conductive tissue in adult birds and mammals. And this knowledge can be put to use in the future.