This baby bird fossil gives a rare look at ancient avian development

The lack of complete breastbone suggests diversity in how some early birds developed

fossil of extinct bird called Enantiornithes

TINY FOSSIL  The breastbone of this fossilized ancient baby bird was still mostly cartilage, rather than bone, when the bird died, meaning it wouldn’t yet have been able to fly, an analysis suggests.

F. Knoll et al/Nature Communications 2018

This baby bird had barely hatched before it died 127 million years ago — and its lack of fully developed bony breastbone, or sternum, suggests it couldn’t yet fly.