The article discusses the largest big cat species, both extinct and current, as shared by members of the Reddit community r/bigcats. It highlights notable species such as the Smilodon populator and the Siberian tiger, detailing their weights and features while noting the complexities in categorizing size among various subspecies.

The article discusses various big cat species, highlighting the largest known species both extinct and current, including the Smilodon populator, American lion, Siberian tiger, and liger. It emphasizes the complexities in determining the largest big cat due to size variability and extinct species estimates, while also suggesting relevant Reddit communities for further discussion.

The article details the theft of thousands of butterflies from Australian museums by collector Colin Wyatt, who used charm to deceive the entomological community. It highlights the discovery of a fake butterfly that had been painted to resemble a rare species, raising concerns about the integrity of collected specimens and their importance to biodiversity research.

The Christmas Island shrew (Crocidura trichura), once abundant on Christmas Island, has been declared extinct due to the introduction of invasive species and habitat destruction. Despite brief rediscoveries in 1958 and 1984, the species could not be saved, highlighting the fragility of ecosystems and the impact of human activities on native wildlife. Its extinction marks the 39th mammal species lost in Australia since colonization, serving as a reminder of the unseen losses in biodiversity.