Think you know rats? Think again. These remarkable rodents are equipped with brilliant survival skills, unique biological quirks and impressive intelligence.
Whether it's their ever-growing teeth, their inability to vomit or their recently-discovered laugh, rats are full of surprises. Here are 10 rat facts you (probably) haven't heard before.
10 amazing rat facts
1. There are more brown rats in the world than any other species
This makes rats the most numerous species on Earth. They make up 40 per cent of all 5,487 species of mammal on Earth.
2. Rats can’t vomit.
Like other rodents, rats can’t trigger the vomiting reflex that other species have, due to muscular and neurological structures. They lack the stomach structure that moves contents towards the oesophagus, and also lack the neural pathways in the brain that usually coordinate the movements involved in vomiting. Did you know horses can't vomit either?
3. The biggest rat in the world is a whopping 3.9kg.
The Sumatran bamboo rat might not be the longest rat, measuring 50cm, but it definitely clocks in at the heaviest.
4. Rats’ whiskers are more sensitive than human fingertips.
They use their whiskers to help guide them around their environments, and also to balance. They can therefore survive – and thrive – with relatively poor vision. It’s therefore advised for rat owners to never trim their pet’s whiskers.
5. The world’s deadliest rat carries enough toxin to kill an elephant.
The crested rat (also known as the maned rat or African crested rat) is the only known poisonous rodent, and one bite is enough to kill its prey in one.
6. Rats’ teeth never stop growing.
It’s the same for all rodents – they continue growing throughout their life, so they’re able to gnaw with the best possible gnashers without worrying about wearing them down.
7. The naked mole-rat can survive 18 minutes without oxygen – and feel no pain.
The naked mole-rat is definitively one of the weirdest species of rat in the world, living like insects with a single breeding queen that remains fertile right up until her death. Naked mole-rats can also live up to 30 years of age, making them one of the longest-living rodents.
8. Rats are known for their impressive fecundity.
Rats begin breeding from about five weeks of age and continue on until about the age of two. Females are fertile roughly every three weeks, and males can ejaculate multiple times in a row, increasing the likelihood of pregnancy. Females can also become pregnant again within 24 hours of giving birth.
9. Rats “laugh” when they’re being tickled – and they enjoy it.
Researchers discovered that rats could laugh in 2016 when the rats let out “laughs”, which are too high pitched for us to hear but can be recorded with microphones and augmented to be heard at a lower pitch. The rats were also shown to chase the researchers’ hands to be tickled again.
10. Rats can be trained to do pretty much anything.
They can be trained to do everything from detecting bombs – as in the case of the African giant pouched rat – or play basketball.
11. Rats are great swimmers
Not only are rats great swimmers but they can also hold their breath for three minutes
Top image: Brown rat (credit: Getty Images)