Head to head
Southern Cassowary vs Emu
The cassowary and the emu are Australia's two big flightless birds and each other's closest relatives, but they live very differently. The emu is a lean grey wanderer of the open outback; the cassowary is a heavy, armour-headed, brilliantly coloured bird of dense rainforest with a reputation as the most dangerous bird alive.
| Southern Cassowary | Emu | |
|---|---|---|
| Habitat | Tropical rainforest of NE Australia and New Guinea | Open scrub, grassland, and woodland across Australia |
| Height | 1.5–1.8 m | 1.5–1.9 m |
| Weight | 55–75 kg (females largest) | 30–55 kg |
| Head | Tall keratin casque; blue-and-red bare skin, wattles | Plain, feathered, no casque |
| Inner claw | Straight dagger up to ~12 cm | Blunt; the kick still hurts but no dagger |
| Temperament | Wary but will charge and kick if cornered or fed | Generally calm and curious |
| Diet | Fallen rainforest fruit — a key seed disperser | Seeds, fruit, flowers, insects — a generalist |
| Conservation status | Least Concern (Australian population near-threatened locally) | Least Concern |
Cassowary vs Emu: common questions
Is the cassowary really the most dangerous bird?
It is the bird with the most serious record of attacks on people. Its forward-driving kick with a long, sharp inner claw can cause deep puncture and slashing wounds, and there are documented fatalities, though they are very rare and usually involve a bird that has been fed by humans and lost its fear.
What is the cassowary's casque for?
It is not fully settled. Proposed functions include a sound resonator for the very low "booming" calls, a signal of age and status, a tool for pushing through dense undergrowth, and possibly heat regulation, as the casque is well supplied with blood.
Are cassowaries and emus related?
Yes — they are each other's closest living relatives, together forming the family group Casuariidae. They diverged tens of millions of years ago and adapted to opposite habitats, the emu to open arid country and the cassowary to closed rainforest.