The ratios of strontium isotopes in fossil shark teeth can be used to better understand how coastal environments evolved in ...
About half a million years ago, several sloths, armadillos, and horses fell into a sinkhole in Florida’s Big Bend region. […] ...
Roughly half a million years ago, a group of armadillo-like mammals, horses, and sloths met their end in a sinkhole in what ...
The age of the teeth helped to clarify the age of the ... scientists could estimate the age of the sites based only on mammal fossils. The sites were thought to be the same age.