- Rats breed so quickly that in just 18 months, 2 rats could have created over 1 million relatives. 
- The blue whale can produce the loudest sound of any animal. At 188 decibels, the noise can be detected over 800 kilometres away. 
- Horses and cows sleep while standing up. 
- Giant Arctic jellyfish have tentacles that can reach over 36 metres in length. 
- Locusts have leg muscles that are about 1000 times more powerful than an equal weight of human muscle. 
- Hummingbirds are so agile and have such good control that they can fly backwards. 
- Instead of bones, sharks have a skeleton made from cartilage. 
- Insects such as bees, mosquitoes and cicadas make noise by rapidly moving their wings. 
- The horn of a rhinoceros is made from compacted hair rather than bone or another substance. 
- Sharks lay the biggest eggs in the world. 
- The giant anteater has the longest tongue of any mammal in the world, measuring up to 2 feet long! 
- Tiny primates called tarsier have the largest eyes relative to body size of any mammal. 
- A group of flamingos is named a "flamboyance". 
- Even when a snake has its eyes closed, it can still see through its eyelids. 
- Unlike humans, sheep have four stomachs, each one helps them digest the food they eat. 
- Despite the white, fluffy appearance of Polar Bears fur (which is transparent), it actually has black skin. 
- As well as being a famous Looney Tunes character, the Tasmanian Devil is a real animal that is only found in the wild in Tasmania, Australia. It is the largest carnivorous marsupial in the world. 
- The average housefly only lives for 2 or 3 weeks. 
- Mosquitoes can be annoying insects but did you know that it's only the female mosquito that actually bites humans. 
- Cats use their whiskers to check whether a space is too small for them to fit through or not. 
- Some cockroaches can survive without air for over 40 minutes. 
- The only mammals that lay eggs are the platypus and the echidna. 
- Elk antlers can grow as fast as 2.5 cm (1 inch) a day. 
- Skunk spray is powerful enough for humans to notice it from miles away. 
- Salamanders can regenerate (grow back) their limbs, tail, and even their jaw. 
- Kiwis lay eggs that can weigh up to a quarter of their body weight.