A recent remarkable archeologic discovery in Belgium remembers us that angelsharks have evolved during millions of years of evolution, adapting to different climate changes in their habitats.
Shark fossil remains were found in clay layers that were deposited 28 to 34 millions of years ago. A group of scientists from Belgium and Holland identified these as parts of a braincase and vertebras from an angelshark species.
Actually, the researchers are analysing the braincase to confirm to which ancestor of the actual angelsharks it belongs. This study can also help to understand of how these sharks have evolved.
The complete study is available in Contributions to Zoology: Mollen FH, Barry WM, van Bakel BWM, Jagt JWM (2016) A partial braincase and other skeletal remains of Oligocene angel sharks (Chondrichthyes, Squatiniformes) from northwest Belgium, with comments on squatinoid taxonomy.