Tag: bird

Copepteryx

Copepteryx hexeris, a plotopterid bird from the Late Oligocene of Japan (~28-23 mya).

Known from around the North Pacific rim from about 33-15 million years ago, plotopterids were flightless diving birds which used their small but powerful wings to propel themselves through the water. They were convergently similar to penguins in body shape and lifestyle, but not actually closely related to them – instead being relatives of gannets, cormorants, and anhingas.

Smaller plotopterids were about the size of modern cormorants, around 70cm long (2′4″), but the larger known genera like Copepteryx rivalled the southern giant penguins at around 1.8m (6′).

And a second species of Copepteryx known only from a single leg bone (Copepteryx titan) may have been ever bigger. Estimated at over 2m in length (6′6″), it was possibly one of the largest diving birds to have ever lived.

Ergilornis

Ergilornis rapidus, a 1.2-1.5m tall bird (4′-5′) from the Early Oligocene of Mongolia (~33-28 mya). Closely related to modern cranes, trumpeters, and limpkins, it was part of an extinct group called eogruids – flightless birds which existed across Eurasia for a large portion of the Cenozoic from roughly 40-3 million years ago.

Although the earliest known eogruids were smaller and less specialized, and may even have still been somewhat capable of flying, later forms like Ergilornis had highly reduced wings, long legs adapted for running, and convergently ostrich-like feet with only two toes each.

Longipteryx

Longipteryx chaoyangensis, an enantiornithine from the Early Cretaceous of China, about 120 million years ago. With a body length of only around 15cm (6″), it had a long snout tipped with a few hooked teeth and feet capable of perching – features that indicate it may have lived very similarly to modern kingfishers, feeding on fish and small invertebrates in its swampy forest habitat.

The enantiornithines were a sort of “cousin” lineage to modern birds. Most had toothy jaws and clawed wings, and the wide variety in their skull shapes suggests that they were specialized for many different dietary niches. The entire group went extinct during the K-Pg mass extinction and left no living descendants, but during the Cretaceous they were the most widespread and diverse group of birds*, with fossils currently known from every continent except Antarctica.

* Depending on how you define “bird”.

Jamaican flightless ibis

The Jamaican ibis (Xenicibis xympithecus) was a bird unique to the Caribbean island of Jamaica. One of only two known types of completely flightless ibises, it was similar in size to a chicken – probably around 75cm long (2′5″) and weighing 2kg (4.4 lbs).

It had some incredibly unusual wing anatomy, with strengthened bones, a proportionally short forearm, and the “hand” section modified into a thick club-like shape. Some remains show evidence of blunt-force injuries, suggesting these birds fought each other by swinging around their heavy wings like baseball bats.

Its bones have found in several cave deposits which are difficult to accurately date, but are likely to be somewhere between 10,000 and 2,200 years old. It’s unclear whether Xenicibis was still around when humans first colonized the island, but if so it was probably driven to extinction soon after.

Turtle-jawed moa-nalo

The turtle-jawed moa-nalo (Chelychelynechen quassus) was a large flightless goose-like duck from the Hawaiian island of Kaua‘i. About 90cm tall (3′) and weighing around 7kg (15lbs), these birds and their relatives were descended from dabbling ducks and existed on most of the larger Hawaiian islands for the last 3 million years or so – before going extinct around 1000 years ago following the arrival of Polynesian settlers.

Chelychelynechen had an unusually-shaped bill, tall and broad with vertically-oriented nostrils, convergently similar to the beak of a turtle. It would have occupied the same sort of ecological niche as giant tortoises on other islands, filling the role of large herbivore in the absence of mammals.

Bathornis

Bathornis grallator, a flightless bird about 75cm tall (2′6″) from the Late Eocene and Early Oligocene of Midwestern USA (~37-34 mya).

It was originally mistaken for a long-legged vulture (under the name Neocathartes) when first discovered in the 1940s, but later studies have shown it was actually one of the smaller members of the bathornithids – close cousins of the more well-known South American “terror birds”, successfully occupying terrestrial predator niches alongside large carnivorous mammals.