Paleo Profile: New Caledonia’s Giant Fowl

A restoration of Sylviornis. From Worthy et al., 2016.
A restoration of Sylviornis. From Worthy et al., 2016.

Life gets weird on islands. Some species, such as elephants, shrink over time, while forms of life that are tiny on the mainland expand to unheard of sizes. Among the best examples of this Island Rule—which is really more of an Island Puzzle—are birds. Over and over again, islands have hosted populations of ground-dwelling, supersized birds, such as one hefty fowl that strutted around New Caledonia.

François Poplin named the bird Sylviornis neocaledoniae in 1980. Exactly what sort of avian it was, however, has been in dispute ever since then. Poplin considered the helmet-headed bird to be related to cassowaries and emus, while other experts suggested that Sylviornis was much closer to turkey-like megapodes. Then further analysis of the skull led other avian experts to put Sylviornis in its own special lineage, the Sylviornithidae, asserting that the turkey-like features of the birds bones were a case of convergence.

In order to sort through this tangle, paleontologist Trevor Worthy and colleagues had a look at about 600 bones of the bird’s body. What they found supported some earlier suggestions about where the bird nested in the greater avian family tree – Sylviornis was a stem galliform, or a relatively archaic member of the group that contains turkeys, pheasants, and chickens. And this might rule out Sylviornis as the answer to a New Caledonian mystery.

Strange earthen mounds on New Caledonia were thought to be the nests of the massive Sylviornis. But this connection relied on the idea that the big bird was a megapode, as these birds characteristically deposit warm their eggs in holes or little hillocks of soil to gain warmth from rotting vegetation, the earth, or some other outside source. Now that Worthy and coauthors have pushed Sylviornis further away from the megapodes, the idea that the mystery mounds were made by Sylviornis now seems less likely. The anatomy of the bird’s feet, the researchers conclude, was at best suited to scratching at the dirt as if it were a supersized chicken. Perhaps, as paleontologists scratch at the soil themselves, they’ll uncover more clues about the life and times of this long-lost fowl.

Some of the Sylviornis long bones examined in the study. From Worthy et al., 2016.
Some of the Sylviornis long bones examined in the study. From Worthy et al., 2016.

Fossil Facts

Name: Sylviornis neocaledoniae

Age: Over 5,500 years ago until about 3,000 years ago.

Where in the world?: New Caledonia

What sort of critter?: A bird related to landfowl like turkeys and pheasant.

Size: Over two and a half feet tall and more than 60 pounds.

How much of the creature’s body is known?: Thousands of individual elements from the skeletons of multiple individuals.


Worthy, T., Mitri, M., Handley, W., Lee, M., Anderson, A., Sand, C. 2016. Osteology supports a steam-galliform affinity for the giant extinct flightless birds Sylviornis neocaledoniae (Sylviornithidae, Galloanseres). PLOS ONE. doi: 10.1371/journal.pone.0150871

Previous Paleo Profiles:

The Unfortunate Dragon
The Cross Lizard
The South China Lizard
Zhenyuan Sun’s dragon
The Fascinating Scrap
The Sloth Claw
The Hefty Kangaroo
Mathison’s Fox
Scar Face
The Rain-Maker Lizard
“Lightning Claw”
The Ancient Agama
The Hell-Hound
The Cutting Shears of Kimbeto Wash
The False Moose
“Miss Piggy” the Prehistoric Turtle
Mexico’s “Bird Mimic”
The Greatest Auk
Catalonia’s Little Ape
Pakistan’s Butterfly-Faced Beast
The Head of the Devil
Spain’s Megatoothed Croc
The Smoke Hill Bird
The Vereda Hilarco Beast
The North’s Sailback
Amidala’s Strange Horn
The Northern Mantis Shrimp
Spain’s High-Spined Herbviore
Wucaiwan’s Ornamented Horned Face
Alcide d’Orbigny’s Dawn Beast
The Shield Fortress
The Dragon Thief
The Purgatoire River’s Whale Fish
Russia’s Curved Blade
The Dawn Mole
The Oldest Chameleon
The Wandering Spirit
Teyú Yaguá

2 thoughts on “Paleo Profile: New Caledonia’s Giant Fowl

  1. so why don’t think the mounds were made by these birds?

    the brush turkey that lives across the sea in australia also makes giant mounds to warm their eggs. the mounds are a whole lot bigger than the turkeys and it doesn’t seem obvious from the outset that they are capable of making those giant mounds with the feet they have. they do also use the feet to scratch around and forage.

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