Two monkeys grooming each other about 20-30 million years ago may have helped produce a remarkable new find – the first fossilized red blood cells from a mammal, preserved so perfectly in amber that they appear to have been prepared for display in a laboratory. The blood cells were caught oozing out of two cuts on the back of an ancient tick just as it became stuck in tree sap that later fossilized into amber.
The discovery was published in the Journal of Medical Entomology by entomologist George Poinar in the Department of Integrative Biology. In the article, he describes the only known fossils of a type of parasite that still exists today, Babesia microti, which infects the blood cells of humans and other animals.