Rodent rubbish as an Ice-Age thermometer
Fossilized garbage piles left behind by pack rats provide clues about temperatures long ago.
![860_rodent_rubbish.png](https://www.snexplores.org/wp-content/uploads/2019/11/860_rodent_rubbish.png)
Pack rats, like this white-throated woodrat, have a habit of gathering wood, cactus parts, stones, bones, and other items to build their piles.
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