# 12 Amazing Facts About Kangaroos (They Cannot Walk Backwards)

*Australia · JUL 25 2026*

> Kangaroos cannot hop backwards because of their large feet and thick tail, they use elastic tendons that make hopping more efficient the faster they go, and females can pause a pregnancy until conditions improve.

Tendons that work like springs, a tail used as a fifth leg, and the ability to pause a pregnancy. Twelve verified kangaroo facts.

## What are the key takeaways from this briefing?
- Kangaroos cannot hop backwards because of their large feet and rigid tail.
- Elastic tendons make hopping more energy-efficient as speed increases.
- The tail generates as much propulsive force as a human leg during slow movement.
- Embryonic diapause lets a female pause a pregnancy until conditions improve.
- A mother can produce two different milk compositions at the same time.

## Twelve kangaroo facts, fact-checked

Kangaroos are the largest marsupials alive and the only large animals that hop as their main gait. Full profile in our [kangaroo guide](/wildlife-guides/kangaroo/).

### 1. They cannot hop backwards

Large feet and a thick, inflexible tail make reversing impossible — part of why the kangaroo appears on Australia's coat of arms as a symbol of moving forward.

### 2. Hopping gets more efficient with speed

Elastic tendons in the legs store and return energy like springs, so a kangaroo uses barely more energy at 20 km/h than at 10.

### 3. The tail is a fifth leg

When walking slowly, a kangaroo supports its weight on its tail and produces as much propulsive force with it as with a human leg.

### 4. Females can pause a pregnancy

Embryonic diapause holds a fertilised embryo in suspension until conditions improve or the current joey leaves the pouch.

### 5. A mother can produce two milks at once

Different teats supply different compositions simultaneously — one for a newborn, one for an older joey still returning to the pouch.

### 6. Newborns are about 2 cm long

Born blind and hairless, a joey crawls unaided through the fur to the pouch.

### 7. Red kangaroos reach 2 m tall

Large males can exceed 90 kg, making them the largest marsupials alive.

### 8. They can reach 70 km/h

Sustained speed is far lower, but red kangaroos can hit around 70 km/h in short bursts and clear 8 m in one hop.

### 9. Males box, and it is serious

Sparring uses forearms to grapple and the tail as a brace for a two-footed kick that can be genuinely dangerous.

### 10. They wet their forearms to cool down

Saliva evaporating from a dense surface network of blood vessels is an effective heat-loss mechanism in hot, dry country.

### 11. They are ruminant-like, but not ruminants

Kangaroos ferment plant matter with gut microbes but produce far less methane than cattle, which has attracted agricultural research interest.

### 12. Most species are not threatened

The large kangaroos are abundant and commercially harvested, while several smaller macropods are threatened or already extinct.

**[Read the full kangaroo wildlife guide](/wildlife-guides/kangaroo/)** for IUCN status, population context and sources — or **[donate to WARN](/donate/)** to help fund the partner teams protecting wildlife on the ground.

## What do people ask about this briefing?
### Can kangaroos walk backwards?
No. Their large hind feet and thick, inflexible tail make reversing impossible. This is one reason the kangaroo appears on Australia's coat of arms, as a symbol of only moving forward.

### How fast can a kangaroo hop?
Red kangaroos can reach around 70 km/h in short bursts and clear about 8 metres in a single hop. Cruising speed is much lower, but hopping becomes more energy-efficient as speed rises because leg tendons store and return energy like springs.

### What is embryonic diapause?
The ability to hold a fertilised embryo in suspended development until conditions improve or the current joey leaves the pouch. It lets a female time births to rainfall and food availability rather than to a fixed cycle.

### How big is a newborn kangaroo?
About 2 centimetres — blind, hairless and roughly the size of a jellybean. It crawls unaided through its mother's fur to the pouch, where it attaches to a teat and continues developing.

### Are kangaroos dangerous?
Large males can be. They grapple with their forearms and brace on the tail to deliver a two-footed kick powerful enough to cause serious injury. Attacks on people are uncommon but not unknown, particularly where kangaroos have been fed by humans.

## Which sources does this briefing use?
- [IUCN Red List](https://www.iucnredlist.org/)
- [Smithsonian's National Zoo — Kangaroo](https://nationalzoo.si.edu/animals)

Human-readable page: https://worldanimalrescuenetwork.org/newsroom/kangaroo-12-amazing-facts/