The only large animal that hops, and the largest marsupial alive. Its legs work like springs, so going faster costs it almost nothing extra. Its tail works as a fifth leg. A mother can hold one embryo on pause, nurse a newborn the size of a bean, and feed an older joey a different milk, all at once.

How hopping worksSee the numbers
FamilyMacropodidae
Lives inAustralia and New Guinea
IUCN statusLeast Concern
DietGrass and shrubs
KANGAROOS AT A GLANCE

"Kangaroo" usually means the four largest members of the family Macropodidae: the red, eastern grey, western grey and antilopine kangaroos. The red kangaroo (Osphranter rufus) is the biggest, with males reaching about 90 kg. All are grazing marsupials of Australia’s grasslands and open woodland. They move by hopping on two long hind legs, live in loose groups called mobs, and raise their young in a pouch. The wider family has more than 60 species, including wallabies, tree-kangaroos and the quokka. The large kangaroos are abundant and listed as Least Concern.

Figures graded and sourced in the fact sheet below. Most numbers are for the red kangaroo.
KEY DISCOVERIES
1770A word written downOn the Endeavour River, James Cook’s crew record "kanguru" from Guugu Yimithirr speakers.
1960sPaused pregnancyResearchers show a kangaroo embryo can wait in the womb, undeveloped, until the pouch is free.
1973Cheap speedOn a treadmill, red kangaroos use no more oxygen at 22 km/h than at 7 (Dawson & Taylor).
2014A fifth legAt walking pace the tail pushes as hard as the front and back legs put together (O’Connor et al.).
2015Left-handedWild red and eastern grey kangaroos prefer the left hand for feeding and grooming (Giljov et al.).
2020Asking for helpFaced with a box they cannot open, 10 of 11 kangaroos look to a person (McElligott et al.).
ONLY IN THE KANGAROO

What makes the kangaroo unlike any other animal?

Short answer: It is the only large animal that gets around by hopping, and its way of breeding lets one mother run three young at different stages at once.

01Speed for freeTendons in the legs store and return energy on every bounce, so a faster hop costs barely more than a slow one.Dawson & Taylor 1973
02A fifth legWhen grazing, it plants its tail and swings both hind legs forward. The tail does as much work as a human leg does in walking.O’Connor et al. 2014
03Pregnancy on pauseA fertilised embryo of about 100 cells can wait for months until the older joey leaves the pouch.Tyndale-Biscoe & Renfree 1987
04Two milks at onceOne teat makes thin, sugary milk for a newborn while another makes rich, fatty milk for a joey at foot.Tyndale-Biscoe 2005
05Mostly left-handedOutside humans, kangaroos show one of the strongest hand preferences known in any mammal.Giljov et al. 2015
06The largest marsupialA big male red kangaroo stands as tall as a person and weighs up to about 90 kg.Dawson 2012
FACT SHEET

How big and how fast is a kangaroo?

Short answer: A male red kangaroo stands up to about 1.8 m and weighs up to about 90 kg. It cruises at 20 to 25 km/h and can sprint at around 60.

MeasuredEstimatedQuoted, unverified
Standing heightMeasuredup to ~1.8 mMale redup to ~1.8 mFemale red~1.1 mMales can rear taller on tail and toes when fighting. Dawson 2012
WeightMeasured~18 to 90 kgMale redup to ~90 kgFemale red18 to 40 kgMales keep growing through life and can be more than twice the weight of females
Top speedEstimated~60 km/hShort burst~60 km/hCruising20 to 25 km/hBursts over short distances. It can hold the cruising pace for kilometres
Longest leapEstimated~8 to 9 mFast hop8 to 9 mReported, 195112.8 mThe 12.8 m bound was reported during a chase and not measured to modern standards
Cost of hoppingMeasuredflat from 7 to 22 km/hAt 7 km/hbaselineAt 22 km/habout the sameOxygen use on a treadmill. Above 18 km/h, hopping is cheaper than running on four legs. Dawson & Taylor 1973
NewbornMeasuredunder 1 gLength at birth~2.5 cmPregnancy~33 daysBlind, hairless, with working front limbs only. Tyndale-Biscoe & Renfree 1987
Time in the pouchMeasured~8 monthsLeaves for good~235 daysWeaned~12 monthsRed kangaroo. Grey kangaroos take several months longer
PopulationEstimated~35 to 50 millionLarge kangaroos~35 to 50 millionPeople in Australia~27 millionSurveyed harvest zones only. Numbers rise and crash with rain and drought. Australian Government estimates
Clears a 3 m fenceQuoted, unverified?Often quoted. Hops of about 1.8 m high are well documented; 3 m is repeated without a measurement we could trace.Popular claim
Speed Race tool →
HOPPING

Why do kangaroos hop?

Short answer: Because for a kangaroo it is the cheapest way to travel fast. The long tendons of the hind legs act as springs, and each landing loads them for the next take-off.

Read: the physics of the kangaroo jump →
01LandBoth feet hit together and the ankle folds under the animal’s weight.
02StretchThe Achilles tendons stretch like thick rubber bands, storing energy.
03RecoilThe tendons snap back and return much of that energy to the next hop.
04LengthenTo go faster it takes longer hops, not quicker ones. Hop rate stays nearly constant.
05BreatheEach hop swings the gut like a piston, pushing air in and out of the lungs at no extra cost.
Oxygen used at different speedsKangaroo, 7 km/hbaselineKangaroo, 22 km/habout the sameRunning mammal, 22 km/hhigherSchematic, after Dawson & Taylor 1973. Below about 6 km/h hopping is inefficient, which is why kangaroos switch to the five-limbed walk.
Slow gearAt grazing pace it uses hands, tail and feet in turn. This "pentapedal" walk is costly, so kangaroos avoid long slow journeys.
Legs move togetherOn land the hind legs cannot easily move one at a time. In water, they kick alternately.
Built for distanceCheap cruising lets kangaroos range widely for patchy grass and water in dry country.
A size limitTendon stress rises with body size. Extinct giant kangaroos were probably too heavy to hop fast.
Alexander & Vernon 1975; Kram & Dawson 1998; O’Connor et al. 2014.
POUCH AND JOEY

How does a kangaroo’s pouch work?

Short answer: The joey is born tiny, after about a month, and finishes developing attached to a teat inside the pouch. It is not born in the pouch: it climbs there by itself.

Read: how the kangaroo pouch works →
Day 0BirthA newborn the size of a jellybean emerges from the birth canal.
~3 minutesThe climbUsing only its front limbs, it hauls itself through the fur to the pouch.
Months 0 to 2AttachedIt latches on to a teat, which swells in its mouth, and stays fixed there.
Months 6 to 8Head outIt starts to look out, then to hop in and out, diving back in head first.
To ~12 monthsAt footOut of the pouch for good, it still puts its head in to drink.
A spare embryoThe mother mates again soon after birth. The new embryo stops developing until suckling by the pouch young eases off.
Milk that changesMilk composition shifts through lactation, from dilute and sugary to rich in fat and protein.
Drought switchIn severe drought females stop breeding. When rain returns, a paused embryo restarts within days.
Inside the pouchIt is warm, hairless and has four teats. The mother cleans it with her tongue.
Three young at onceA female red kangaroo in good seasons can have a joey at foot, a younger one in the pouch and a paused embryo in the womb. If the pouch young dies, the embryo resumes and is born about a month later.Tyndale-Biscoe & Renfree 1987.
DRY-COUNTRY BODY

How do kangaroos survive in the outback?

Short answer: By spending little and wasting little. They rest through the heat, cool themselves by licking their forearms, make very concentrated urine and can travel far for food at low cost.

Forearm lickingA dense net of blood vessels lies just under the skin of the forearms. Wet with saliva, it works as a radiator.
Shade by dayKangaroos lie up under trees in the hottest hours and feed at dusk, at night and at dawn.
A fermenting stomachA long, chambered stomach breaks down tough grass with microbes, a little like a cow’s.
Teeth on a conveyorMolars erupt at the back, move forward as they wear, and fall out at the front.
Wide viewEyes set high and to the side give a broad field of view, and the ears turn separately.
The tailHeavy and muscular. It balances the body in a hop and props it up at rest and in a fight.
LifespanMost die young. Survivors can reach about 20 years in the wild.
SwimmingKangaroos swim well and will take to water to escape dingoes or dogs.
Dawson 2012.
MOBS AND BOXING

Do kangaroos really box?

Short answer: Males do fight, but it is closer to wrestling and kicking than boxing. They grapple with the forearms, then lean back on the tail and kick with both hind feet.

01ChallengeA male approaches stiff-legged, scratching his chest or pulling at grass.
02Stand tallBoth rise on toes and tail to show their height.
03GrappleThey lock forearms and paw at each other’s head and shoulders.
04KickBalanced on the tail, one drives both hind feet into the other’s belly.
05YieldThe loser breaks off and moves away. Serious injury is uncommon.
MobsGroups are loose. Animals join and leave freely, and the core is females with their young.
Dominant malesThe largest male in an area does most of the mating, and holds that place for a year or so.
Alarm thumpA kangaroo that spots danger thumps the ground with its hind feet as it bounds off.
Looking to peopleIn one study, captive kangaroos used to people that could not open a food box looked back and forth between it and a person.
Dawson 2012; McElligott et al. 2020.
KINDS OF KANGAROO

How many kinds of kangaroo are there?

Short answer: Four species are called kangaroos. The same family holds about 60 others, from wallaroos and wallabies to tree-kangaroos.

Read: red kangaroo →
Red kangarooOsphranter rufusArid and semi-arid inlandThe largest. Males are rusty red, females often blue-grey.MalesUp to ~90 kg
Eastern grey kangarooMacropus giganteusEastern Australia and TasmaniaThe kangaroo of farms, golf courses and city edges in the east.MalesUp to ~66 kg
Western grey kangarooMacropus fuliginosusSouthern and western AustraliaBrowner, with a strong smell in males. Also on Kangaroo Island.MalesUp to ~54 kg
Antilopine kangarooOsphranter antilopinusTropical northA slender kangaroo of the monsoon woodlands.MalesUp to ~50 kg
WallaroosStocky, shaggy relatives of rocky hills, between a wallaby and a kangaroo in size.
WallabiesNot a natural group: the name covers most smaller members of the family.
Tree-kangaroosAbout 14 species in New Guinea and far north Queensland that went back up into the trees.
QuokkaA cat-sized relative from Western Australia, best known from Rottnest Island.
Read: quokka →
EVOLUTION

What are kangaroos related to?

Short answer: Koalas, wombats and possums. Kangaroos descend from small, possum-like animals that came down from the trees and took to hopping as Australia dried out and grasslands spread.

Read: marsupials, Australia’s pouched mammals →
Platypus and echidnasEgg-laying mammalsOpossumsAmerican marsupialsTasmanian devil and quollsMeat-eating marsupialsKoala and wombatsThe kangaroos’ closest cousinsGiant short-faced kangaroosExtinct; too heavy to hop fastKangaroosRed, grey and antilopineMarsupialsAustralian marsupialsDiprotodontsKangaroo family
Relationships simplified, not to time scale. After Meredith et al. 2009. Opossum, Tasmanian devil and giant kangaroo outlines: PhyloPic, CC0.
ProcoptodonA short-faced kangaroo that stood over 2 m and weighed more than 200 kg. It died out about 45,000 years ago.
Giants that walkedThe bones of the giant short-faced kangaroos suggest they strode on two legs, one foot at a time.
Back into the treesTree-kangaroos evolved from ground-living, hopping ancestors and climb with strong arms.
Janis et al. 2014. Platypus profile →
KANGAROOS AND PEOPLE

Are kangaroos endangered?

Short answer: No. The four large kangaroos are among the most numerous large wild mammals on Earth, and all are Least Concern. Several smaller relatives are threatened, and how the large ones are managed is hotly argued.

Endangered register →
Boom and bustNATURALNumbers can double in a run of wet years and halve in a drought. Farm dams and cleared pasture have favoured the large species.
Commercial harvestDEBATEDKangaroos are shot for meat and leather under government quotas set as a share of surveyed numbers. Supporters call it sustainable use; critics object on welfare grounds.
RoadsHIGHKangaroos are the animal most often hit by vehicles in Australia, mostly around dusk and dawn.
Aerial surveysGovernments count kangaroos from aircraft each year and adjust quotas to the result.
Protected by lawAll kangaroos are protected native animals. Killing one requires a licence.
Smaller relativesRock-wallabies, bettongs and tree-kangaroos get fenced reserves, fox control and captive breeding.
First peoplesKangaroos have been hunted, eaten and painted in Australia for tens of thousands of years.
Coat of armsA red kangaroo and an emu hold Australia’s shield. Both are popularly said to be unable to walk backwards.
DingoesThe dingo is the main natural predator. Where dingoes are fenced out, kangaroo numbers run higher.
Keep your distanceA cornered male can injure a person with a kick. Attacks are rare and deaths very rare.
Australian Government kangaroo population estimates; IUCN Red List.
MYTH OR FACT

Six kangaroo claims, checked

2Myths3Half true1Facts
01MYTH"Kangaroo" means "I don’t understand".WHERE IT CAME FROMA story told since the 1800s.
WHAT THE EVIDENCE SAYSThe word comes from "gangurru", the Guugu Yimithirr name for a kind of large grey kangaroo. A linguist confirmed it with speakers in the 1970s.
WHAT IS TRUE INSTEADA real word for a real animal.Sources: 12
02MYTHJoeys are born in the pouch.WHERE IT CAME FROMThe newborn is almost never seen.
WHAT THE EVIDENCE SAYSThe joey is born through the birth canal and crawls unaided to the pouch, where it attaches to a teat.
WHAT IS TRUE INSTEADBorn outside, then climbs in.Sources: 06
03HALF TRUEKangaroos cannot move backwards.WHERE IT CAME FROMThe long feet and heavy tail make it look impossible.
WHAT THE EVIDENCE SAYSThey cannot hop backwards with any ease, but they can shuffle back a few steps, and are seen doing so in fights.
WHAT IS TRUE INSTEADAwkward, not impossible.Sources: 01
04HALF TRUEKangaroos box.WHERE IT CAME FROMFairground "boxing kangaroo" shows.
WHAT THE EVIDENCE SAYSMales spar with their forearms, but the damaging blows are kicks delivered while leaning back on the tail.
WHAT IS TRUE INSTEADMore kick-boxing than boxing.Sources: 01
05HALF TRUEKangaroos produce no methane.WHERE IT CAME FROMThey digest grass without belching like cattle.
WHAT THE EVIDENCE SAYSMeasurements show kangaroos do release methane, though less than a cow or sheep for the food they eat.
WHAT IS TRUE INSTEADLess methane, not none.Sources: 10
06FACTA kangaroo can move its hind legs separately when swimming.WHERE IT CAME FROMObserved in rivers and dams.
WHAT THE EVIDENCE SAYSOn land the hind legs work as a pair. In water they kick alternately, in a dog-paddle.
WHAT IS TRUE INSTEADTrue.Sources: 01
OPEN QUESTIONS

What science still doesn’t know

?Why did hopping evolve?Cheap travel in open country is the usual answer. Why no other large mammal does it is not understood.
?How is the embryo paused?Hormones tied to suckling are involved, but the full control of the pause and restart is still being worked out.
?Why left-handed?Standing upright frees the hands, which may favour a preferred side. The brain basis is unknown.
?How many are there?Surveys cover the harvest zones well and the rest of the continent poorly.
?What killed the giants?Hunting by the first Australians and a drying climate are both blamed for the loss of giant kangaroos.
?How do they find rain?Red kangaroos move towards distant storms. Whether they smell, see or hear them is unclear.
FAQ

Frequently asked questions

How fast can a kangaroo go?+

It cruises at 20 to 25 km/h and can reach about 60 km/h in a short burst.

How far can a kangaroo jump?+

A fast-moving red kangaroo covers 8 to 9 m in a single hop.

How big is a newborn kangaroo?+

About 2.5 cm long and under 1 g, roughly the size of a jellybean.

How long does a joey stay in the pouch?+

A red kangaroo joey leaves the pouch for good at about 8 months and is weaned at about a year.

What do kangaroos eat?+

Mainly grasses, plus herbs and shrubs. They ferment food in a chambered stomach.

Are kangaroos endangered?+

No. The four large kangaroo species are abundant and listed as Least Concern.

COMPARE AND EXPLORE

Explore kangaroos further

TOPICMarsupialsOpen →PROFILEPlatypus profileOpen →TOOLSpeed RaceOpen →TOOLSize ComparisonOpen →
HOW WE KNOW

Sources and how we check

This page is written by Strange Animals and checked against primary research. Every figure carries a grade and a numbered source.

Cite this pageStrange Animals. (2026, November 15). Kangaroo (Osphranter and Macropus): hopping, pouch, body and species. https://strangeanimals.info/mammals/marsupials/kangaroo
  1. 01Dawson, T. J. Kangaroos, 2nd edition. CSIRO Publishing2012
  2. 02Dawson, T. J. and Taylor, C. R. Energetic cost of locomotion in kangaroos. Nature 246: 313-3141973
  3. 03Alexander, R. McN. and Vernon, A. The mechanics of hopping by kangaroos (Macropodidae). Journal of Zoology 177: 265-3031975
  4. 04Kram, R. and Dawson, T. J. Energetics and biomechanics of locomotion by red kangaroos (Macropus rufus). Comparative Biochemistry and Physiology B 120: 41-491998
  5. 05O’Connor, S. M. et al. The kangaroo’s tail propels and powers pentapedal locomotion. Biology Letters 10: 201403812014
  6. 06Tyndale-Biscoe, H. and Renfree, M. Reproductive Physiology of Marsupials. Cambridge University Press1987
  7. 07Tyndale-Biscoe, H. Life of Marsupials. CSIRO Publishing2005
  8. 08Giljov, A. et al. Parallel emergence of true handedness in the evolution of marsupials and placentals. Current Biology 25: 1878-18842015
  9. 09McElligott, A. G. et al. Kangaroos display gazing and gaze alternations during an unsolvable problem task. Biology Letters 16: 202006072020
  10. 10Vendl, C. et al. Decreasing methane yield with increasing food intake keeps daily methane emissions constant in two foregut fermenting marsupials, the western grey kangaroo and red kangaroo. Journal of Experimental Biology 218: 3425-34342015
  11. 11Janis, C. M., Buttrill, K. and Figueirido, B. Locomotion in extinct giant kangaroos: were sthenurines hop-less monsters?. PLoS ONE 9: e1098882014
  12. 12Haviland, J. B. A last look at Cook’s Guugu Yimidhirr word list. Oceania 44: 216-2321974
  13. 13Meredith, R. W., Westerman, M. and Springer, M. S. A phylogeny of Diprotodontia (Marsupialia) based on sequences for five nuclear genes. Molecular Phylogenetics and Evolution 51: 554-5712009
  14. 14Australian Government Kangaroo population estimates in commercial harvest zones. Department of Climate Change, Energy, the Environment and Watern.d.
  15. 15Ellis, M. et al. (IUCN) Osphranter rufus. IUCN Red List. Least Concern2016
WATCH

Three films worth your time

ClipBBC EarthKangaroo BoxingMale grey kangaroos fight to become the dominant male of the group. From the BBC series Life of Mammals.Pairs with: Mobs and boxing →
ClipAustralian Reptile ParkKangaroo Joey Takes First HopsJellybean, an eight-month-old eastern grey kangaroo joey at the Australian Reptile Park, takes some first hops.Pairs with: Pouch and joey →
ClipMorelia AustraliaFighting Kangaroos Kickboxing and Hopping BackwardsKangaroos fighting, low kicks included, and one that hops backwards.Pairs with: Myths →
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