Did you know hatching is a pretty hectic process for birds? 🐣
When oxygen demand for the growing embryo can’t be met by regular respiration through the shell and membranes, lung respiration begins. The embryo first breaks into the air cell for extra oxygen (internal pip). When air here runs short, it cracks through the shell with an egg tooth, taking its first breath of fresh air (external pip). But it’s not done yet - the chick still has to hatch and break free!
In this photo a king #penguin
(Aptenodytes patagonicus) chick has successfully external pipped. It can be another 12 hours before the chick finally hatches. 🐥💛 #lovemyjob