Mammoth 300,000 years old Going further back in time, the
team tested the skeletal remains of a Columbian mammoth from the Pleistocene.
The hollow, orange-tinged vessels seen here are still flexible,
while those in the inset are crystalline and shatter easily, even though both
came from the same specimen. Why the discrepancy in fossilization? Further studies now needed to
update our understanding of the fossilization process may help tell. The main image also
shows possible red blood cells. The white material is bone matrix that
didn't dissolve in the acid—probably collagen, a chief component of
bone and connective tissue
