Fossil shark teeth are abundant and can date the past in a unique way
The ratios of strontium isotopes in fossil shark teeth can be used to better understand how coastal environments evolved in ...
500,000 years ago, a bunch of animals fell into a Florida sink hole
Roughly half a million years ago, a group of armadillo-like mammals, horses, and sloths met their end in a sinkhole in what ...
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Fossil shark teeth are abundant and can date the past in a unique way
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.