The most difficult car­ni­vores riddles

The saltwater crocodile is the largest of all living reptiles, reaching up to 6.3 m and 1,360 kg. It may be found from Northern Australia to the eastern coast of India.

Only lions live and hunt in groups. A pride of lions consists of related females and offspring and a small number of adult males.

The area of nasal mucous membrane in a bear's head is 7 times greater than a bloodhound's (and one hundred times larger than in a human's). Polar bears have been seen to march up to 40 miles in a straight line to reach a prey animal they have detected.

When the crocodile's mouth is closed, the large fourth tooth in the lower jaw fits into a constriction in the upper jaw. For hard-to-distinguish specimens, the protruding tooth is the most reliable feature to define a species

Siberian tiger males can reach as much as 3.5 m (11ft) in total length and 270–310 kg (600–675 lb) of weight. Lion males reach up to 250 kg.

A group of whales swims in a shrinking circle blowing bubbles below a school of prey. Forage fish show a strong fear of bubbles and can be easily contained within a bubble curtain. The shrinking ring of bubbles encircles the school and confines it in an ever-smaller cylinder. The whales, then suddenly swim upward through the "net", mouths agape, swallowing thousands of fish in one gulp.

The biggest recorded "beachmaster" male of the southern elephant seal was 5,000 kg (11,000 lb) and 6.9 m (22.5 ft) long. A bear can grow up to 1,000 kg - five times less.

Dingos ancestors that were brought to Australia were relatively undomesticated and closer to wild Asian gray wolf. The dingo's diet includes bandicoots, rodents, echidnas, crabs, fruits, and other plants, as well as insects (mostly beetles). On Fraser Island, dignos often eat fish.

Cats are nocturnal predators and therefore have excellent hearing, among the best of any mammal. They can detect an extremely broad range of frequencies, ranging from 55 Hz to 79 kHz. This is far more than humans (31 Hz - 18 kHz), and dogs (67 Hz - 44 kHz). Cat's ability to hear ultrasound is probably important in hunting, since many species of rodents make ultrasonic calls.