One moment there’s nothing, the next … a heartbeat. As a vertebrate embryo grows, its heart tissue starts to pulse well before it’s needed. But how does the developing heart actually coordinate that very first beat?
Read the paper: A bioelectrical phase transition patterns the first vertebrate heartbeats
Using microscopes and glowing fluorescent proteins, researchers have been able to watch zebrafish embryos during this key point in development and examine the process in real time.