Scientists link rising CO₂ to decline of the world's largest bees

Bees are among the world's most important pollinators, supporting wild ecosystems and helping produce many of the crops humans depend on. But while climate change has long been linked to rising temperatures and habitat loss, scientists have now identified another growing threat: increasing atmospheric carbon dioxide (CO₂). A new study suggests that elevated CO₂ levels may be disproportionately harming the world's largest bees, leaving their populations smaller and less genetically diverse while favouring smaller-bodied pollinators. Because larger bees are often the most effective pollinators, the findings raise fresh concerns about the future of global food security and biodiversity.