The Australian redback spider is a highly toxic spider, mainly distributed in Australia, but also in New Zealand, Southeast Asia and Japan. The female spider is about 1cm long and has a black body with red or orange stripes and hourglass marks on her abdomen. The male spider is smaller and lighter in color. The venom contains a neurotoxin that can cause severe pain, swelling, and nausea after being bitten, but antivenom can be an effective treatment. It prefers to inhabit dark, dry environments, such as under rocks, firewood or outdoor furniture, and is nocturnal. Females live up to 2-3 years, males usually only 6-7 months.

Didelphinae is a general term for mammals in the family Didelphinae, belonging to the marsupial order, and is a small to medium-sized mammal. Due to the fact that female opossums can carry their young around and run around, they are named "opossums". Has the largest number of teeth among living land mammals. Nocturnal, gentle temperament, often goes out at night, preys on small invertebrates such as insects and snails, and also eats some plant-based food. When threatened or injured, opossums will roar (especially males), pretend to be dead, and mimic the appearance and scent of sick or dead animals. He is known as the "brake man" because he suddenly stands still while running, confusing predators, and then suddenly jumps up to escape