A new study suggests that pollen clouds from increased vegetation at the end of the last ice age may have contributed to woolly mammoths’ extinction by causing allergic reactions. These allergies could have impaired their sense of smell, disrupting communication and breeding. This theory adds to existing ideas that inbreeding, human hunting, and vegetation changes led to their demise. Researchers propose examining mammoth stomach contents and mummified tissues for pollen and immune proteins to test this hypothesis. The study was published in the journal Earth History and Biodiversity.