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Alexornis

A small, sparrow-like animal with feathers and a toothed beak

WWD - Prehistoric Planet

Alexornis is an extinct, prehistoric bird, which lived at the time of the dinosaurs. It was a small, sparrow-like animal with feathers and a toothed beak.

They call it home

Alexornis lived in an environment of warm, coastal lagoons, swamps, mudflats and forest. It lived alongside dinosaurs like Lambeosaurus.

What we heard about their hearing

What we heard about their hearing

Alexornis and other early birds are thought to have had similar perceptions to modern birds. Archaeopteryx, one of the earlier bird-like dinosaurs, had heightened auditory and sensory perception in the ear and was well adapted to life on the wing.

What big teeth you have

What big teeth you have

Most enantiornithine birds like Alexornis possessed teeth. In fact, there were a variety of different forms of teeth. Like the varied beaks of Darwin's finches, these ancient birds had specialised teeth, well adapted to suit the varying diets of different species.

Nose knowledge

Nose knowledge

Alexornis might have smelled like a dinosaur. Early birds have been studied and found to have had a respectable sense of smell. This sense was eventually lost in later birds as they moved towards a heightened sense of vision and balance.

The most fantastic find

The most fantastic find

Alexornis is known from just one fragmentary fossil of the shoulder, wing and leg. It was discovered by HJ Garbani and J Loewe in 1971 in Baja California, Mexico. Because the remains are so fragmentary, the majority of our knowledge of Alexornis is inferred from other members of their group, the Enantiornithes.

Alexornis features

Alexornis features Height: 0.2m (0.7ft)
Length: 0.15m (0.5ft)
Weight: 0.3kg (0.7lbs)
Top speed: 45kph (28mph)
Vision: Eyesight would have been Alexornis' most important sense. For a life in the skies, good binocular vision is essential.
Skin: Alexornis, like its close relatives, had feathers similar to today's birds. These were asymmetrical flight feathers, which indicates considerable flight capability.
Brain: Alexornis is thought to have had an enlarged forebrain, consistent with other birds leading a life in the air.
Prey: Alexornis probably, like other enantiornithines, relied on their teeth rather than beak to manipulate their food.
Bite: We know very little about the feeding habits of Alexornis. Some enantiornithines had large, robust jaws for eating hard-shelled invertebrates, others had long snouts and thin teeth at the tip of their jaws for probing mud and others had larger teeth for fishing.
Nest: The remnants of a mass breeding colony of an enantiornithine bird has been found in Romania. Given the large volume of eggshells, this colony must have been considerable, consisting of hundreds of nests. The site is consistent with ground nesting birds and is thought to have been left by close relatives of Alexornis.

Alexornis facts and theories

Alexornis facts and theories

  1. One of the most unusual features of birds like Alexornis is that they had teeth, which living birds have lost. Because their dinosaur ancestors had teeth, birds must have lost them at some point during their evolution history. Amazingly, scientists have successfully made chickens grow teeth in laboratory experiments. That means the genetic codes for teeth are still hidden away in the DNA of living birds!
  2. Alexornis were members of a group of prehistoric birds – the Enantiornithes – which went extinct at the end of the Cretaceous along with the dinosaurs. They are not the direct ancestors of modern birds but a side branch that was pruned along the way.
  3. A number of enantiornithines had well-developed hatchlings with wing feathers and a large brain. They were ready to run, forage and even fly within just a few days. This might have meant that they left the nest within just a few days of birth.
  4. Enantiornithines like Alexornis went extinct at the end of the Cretaceous period along with all the dinosaurs.
  5. Enantiornithines had 'bastard wings' – a small pointing arrangement of feathers on the first digit – like modern birds do today. This gave them better manoeuvrability in the air.