Three Things I'm Curious About This Week #15

These collections of patterned rocks by Avery Gregory. There’s something very simple, yet very soothing about these arrangements.

A group of small rocks are carefully spaced in a cluster. Each rock has one or more holes. — Photo by Avery Gregory.

Glass frogs make themselves transparent by hiding their blood in their liver while they sleep. How amazing is that?

A glass frog is viewed from underneath. Its stomach and heart are visible through its transparent body. — Photo by Jesse Delia/AMNH via DW.com

Baudet du Poitou are French draft mules that have been bred since the Roman Empire. The breed declined to just 44 animals in 1977 and efforts are underway to recover this distinctive breed.