Q.Mention the major threats to biodiversity caused by human activities. Explain.

Step 1. The chapter's headline statistic sets the scale: habitat loss, fragmentation and destruction affect about 73% of all species — the single largest human-driven threat category.

Step 2. Habitat loss itself stems from clearing land for settlement, agriculture, mining, industry and highways, while habitat fragmentation further splits remaining habitat into isolated patches that destroy species interactions and disproportionately harm large-territory animals such as elephants and migratory birds.

Step 3. Over-exploitation — hunting, poaching, indiscriminate logging, over-fishing and mining — has already driven species like the Dodo, passenger pigeon and Steller's sea cow extinct, while introduced exotic/alien species (Tilapia, Nile Perch, African apple snail) drive out native species as the second major recognised cause of extinction. …

List the chapter's named human-driven causes of biodiversity decline, leading with the 73% habitat-loss statis …

• Naming causes without the chapter's specific supporting statistic (73% habitat-loss impact) or named species examples. …