Kangaroo rats are desert dwellers: Lifeform of the week
Can you imagine living in sweltering, brutal heat? There’s hardly any water around you. And you’re surrounded by snakes that will not stop trying to eat you…
Meet the kangaroo rat. It’s a tiny rodent with a great big set of tools for thriving in the desert world.
These spring-loaded rodents are not rats
Those survival skills are why Frank Herbert called his main character in the popular sci fi novel Dune by the nickname Muad’Dib. His actual name – known and loved by fans around the world – was Paul Atreides. But Muad’Dib was appropriate. It was the name for the kangaroo rat in the fictional language of the desert Fremen, spoken throughout the book:
Muad’Dib is wise in the ways of the desert. Muad’Dib creates his own water. Muad’Dib hides from the sun and travels in the cool night. Muad’Dib is fruitful and multiplies over the land. Muad’Dib we call ‘instructor-of-boys.’ That is a powerful base on which to build your life, Paul-Muad’Dib.
Back on Earth, kangaroo rats are from the genus Dipodomys. And they’re not rats at all. Although they are rodents, they are a species distinct from rats. On the other hand, kangaroo rats do bear a striking resemblance to – and leap just like – kangaroos. They have enormous hindlegs and long tails, much like kangaroos. But they are pint-sized compared to kangaroos. Their small size varies from 4 to 8 inches (10 to 20 cm). Their tails are as long as their bodies and heads. Sometimes longer! They tip the scales at around 1.2 to 6.3 ounces (35 to 180 g).
Uniquely among rodents, kangaroo rats and their cousins kangaroo mice are bipedal. That is, they move about on two legs. And they move by jumping. Their front legs are much smaller than their back legs. Kangaroo rats use their front legs mainly for holding objects and feeding.
In this way, they’re kind of like a small, furry and adorable T-rex.
‘Muad’Dib is wise in the ways of the desert’
Most members of the genus Dipodomys are found in arid and semi-arid areas of western North America. They range from southern Canada to southern Mexico. A total of 23 species of kangaroo rat are known.
Normally, they feed on seeds, roots, stems, leaves and, occasionally, insects. They are able to survive without drinking water for long periods of time. Most of their hydration comes from the food they eat, which has a high water content.
Unlike the fictional Dune variety, kangaroo rats do not collect dew on their ears. But their kidneys are at least four times more efficient at retaining water and excreting salt than those of humans. Like the desert Fremen clad in their stillsuits, they are adapted to concentrate their urine. This minimizes water loss and maximizes conservation.
In the book, the animal Muad’Dib – like its real kangaroo rat cousins – is nocturnal. This way, earthly kangaroo rats avoid high daytime temperatures and reduce water loss through evaporation.
Harnessing desert power: How kangaroo rats battle snakes and win
Kangaroo rats’ hindlegs seem out of proportion. They’re four times longer than the forelegs. This allows these creatures to jump up to 10 feet (3 m). It’s practically their only defense mechanism against snakes, their biggest native threat. Unfortunately for kangaroo rats, these predators are very, very patient. Luckily, our little friends know how to defend themselves.
The kangaroo rat’s senses let it detect even the slightest low-frequency sounds. It responds within milliseconds. And even the stealthy sound produced by a crawling snake or the flapping of an owl’s wings is warning enough. Our furry friend stops, throws sand with his hindlegs at the predator or makes an impressive jump to save itself.
Even being trapped in a snake’s mouth isn’t certain death. The kangaroo rat can kick its way out before the venom is released. The same kick propels the snakes away.
And when they jump to survive, kangaroo rats swing their long tails to find balance. This leaves them in a good position to escape by jumping again. In a Harkonnen versus Atreides fight, the point goes to Muad’Dib.
All this happens in the blink of an eye. Sometimes, kangaroo rats do lose this battle. But these small animals survive the snakes’ attacks three out of four times to return safely to their burrows. As Muad’Dib learned from the Fremen, often the best defense is a good attack.
The daily family life of kangaroo rats
They are very sociable animals. In fact, they sleep on top of each other to retain body heat, especially if it is winter. And they tap the ground with their big hindlegs to communicate with other kangaroo rats.
Their mating system is generally polygamous. The female gives birth after 40 days of gestation. A litter has three babies on average. After eight or 10 weeks, they are completely independent. They reach sexual maturity at eight or 12 months. Kangaroo rats can live for two to five years.
Most species of kangaroo rat use their burrows as food reserves in case there is a bad season. How thoughtful they are!
Unfortunately, these cute but tough animals have to battle with more than snakes and birds of prey. They are also highly coveted by animal traffickers. This humanmade threat – combined with humanmade reduction of their habitat – has put different families of the kangaroo rat in danger. And some are even on the verge of extinction.
For example, the giant kangaroo rat continues to be threatened by agricultural and urban development, rodenticides, and oil drilling and exploration in California. More than 98% of its habitat has disappeared.
Bottom line: Kangaroo rats are small, desert-adapted rodents. They are highly skilled and know how to defend themselves from different predators, including poisonous snakes.
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