Acipenseriform fish with ejecta clustered in the gill region. (A) X-ray of a fossil sturgeon head (outlined, pointing left; FAU.DGS.ND.161.115.T). (B) Magnified image of the X-ray in A showing numerous ejecta spherules clustered within the gill region (arrows). (C and D) Micro-CT images of another fish specimen (paddlefish; FAU.DGS.ND.161.29.T), with microtektites embedded between the gill rakers in the same fashion.

The Best Evidence Yet for the Dinosaur Killer


Archaeologist Robert A. DePalma, working in Southcentral North Dakota, has found the best evidence yet that the dinosaur killer, the huge meteor that struck the Yucatan Peninsula, leaving the Chicxulub crater, did indeed kill the dinosaurs. He has found, entombed in the rocks of the Hell Creek Formation, the archaeological equivalent of a smoking gun.…