In 1993, landfill workers at the Madera County landfill in California discovered fossils beneath the site.

Since its discovery, more than 15,000 fossils have been unearthed from the site, making it one of the most significant paleontological finds in recent decades.

Still to this day fossils are unearthed from the landfill in what is known as "salvage paleontology." Under their current system landfill workers dig as they need and allow paleontologists to come in and recover fossils as they are found.

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