
A rat with at least four testicles, one larger than its head, published in a scientific journal earlier this year.
Jenny McGrath/Business Insider
Forrest Sheperd
Scientists discovered a new dinosaur species, and it could reshape the history of T. rex's evolution
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Maiya Focht

Here’s something to chew on: a fossilized trilobite from the Ordovician Period, which is so well preserved that a team of paleontologists was able to identify its last meal, now mineralized in the creature’s fossil stomach.
ZHAO Chuang
Wu et al. PNAS 2019, doi.org/10.1073/pnas.1902396116