Nearly Complete Baby Bird Preserved in Amber
Researchers from the Chinese Academy of Sciences in collaboration with colleagues from the Royal Saskatchewan Museum (Canada) and the China University of Geosciences have announced the discovery of yet another prehistoric animal preserved entombed within a 99-million-year-old piece of amber from Myanmar. The animal is a baby bird, perhaps only a few days old when it was engulfed in sticky tree resin back in the Cretaceous. It is an astonishing discovery, one of a number of remarkable fossil finds made in recent years from the amber deposits of northern Myanmar. Most of the skull and neck is preserved along with part of a wing, a hindlimb, complete with claws and some soft tissue surrounding the tail. Some of the plumage has also been encased within the amber nodule. Described as representing a specimen of the Enantiornithes clade, it is the most complete bird preserved in amber found to date.
Enantiornithine Hatchling Preserved in Burmese Amber
Picture Credit: Ryan McKellar (Royal Saskatchewan Museum) et al.
The picture above shows the amber nodule (a). The nodule measures approximately 86 mm × 30 mm × 57 mm it has been assigned the specimen number HPG-15-1 and it has been cut in half. The cut-mark is represented in (c) which shows the cut as a dotted line against a line drawing of the bird’s remains preserved in the nodule. An interpretation of the high-resolution scans showing the skeletal components is shown in (b). The disarticulated remains of this individual has led the research team to speculate that the corpse of this young bird might have been scavenged prior to its entombing in the tree resin.
A Very Young Bird
Writing in the academic journal “Gondwana Research”, the scientists conclude that the shape of the skeleton and the plumage indicates a very young bird, the well-developed wings, claws and the presence of some filamentous body feathers suggests that Enantiornithines were hatched in a relatively advanced state, being perhaps able to feed itself almost immediately. Being born nearly fully developed and independent of the parents is termed precocial. Many modern birds are precocial, examples include ostrich chicks and ducklings. These birds are able to keep themselves warm and move about, often leaving the nest in just a few hours. The scarcity of body feathers on the Cretaceous bird represents a distinct departure from the feather coverings found in today’s precocial birds. Perhaps the Enantiornithines relied on their parents to brood them to keep them warm, or perhaps these birds hatched during the hottest part of the year, when insulation was not as necessary.
A Three-Dimensional Model Created from the High-Resolution Scans
Picture Credit: Ryan McKellar (Royal Saskatchewan Museum)
Commenting on the importance of this fossil discovery, Ryan McKellar (Royal Saskatchewan Museum) stated:
“We’ve had more complete specimens, where you get more of the skeleton preserved, from compression fossils, but never with this level of detail. It’s like a little diorama.”
The amber nodule also contains insect remains, plant material and mites, providing an insight into the fauna and flora of a conifer forest that existed around 99 to 100 million years ago. The amber was found by a miner back in 2014, at first the claw was thought to have come from a lizard but once the piece had been purchased by the Hupoge Amber Museum in Tengchong City, China, a correct identification was made. The specimen was nicknamed “Belone” a local term for an amber-coloured bird called the Oriental skylark.
Researchers including palaeontologist Lida Xing (China University of Geosciences), used CT scans to examine fossil elements hidden from view. These scans revealed the skull and part of the spine, although the cutting of the nodule damaged the anterior portion of the head and the tiny jaws.
As for its feathers, the bird had different kinds: some that palaeontologists have seen on dinosaurs, but others that are closer to modern-day birds. This, the research team commented, was one of the most surprising and rewarding finds.
The Enantiornithine Hind Leg
Picture Credit: Ming Bai
A Precocial Bird
The presence of strong toes equipped with sharp claws suggests that this bird could clamber around in the trees shortly after hatching, yet more evidence of just how independent this young bird was. Precociality is thought to be ancestral in birds. Thus, altricial birds tend to be found in the most derived families within the Aves (birds) Order. There is some evidence for precociality in the Dinosauria. It seems that being independent at birth is a characteristic that is basal to the birds.
A Close View of One of the Claws
Picture Credit: Ming Bai
The amber mines of Kachin Province (northern Myanmar) are renowned for their remarkable fossils, back in 2016, Everything Dinosaur wrote an article about the remnants of a bird’s wing that had been preserved trapped in amber.
To read more: Bird Wing Trapped In Amber
Later that year, Everything Dinosaur reported on discovery of a fragment of a dinosaur’s tail that had been found preserved inside amber. That remarkable specimen was studied by a number of the researchers who contributed to the study of this baby bird fossil.
To read more about the dinosaur tail discovery: The Tale of a Dinosaur Tail
The scientific paper: “A mid-Cretaceous Enantiornithine (Aves) Hatchling Preserved in Burmese Amber with Unusual Plumage” by Lida Xing, Jingmai K. O’Connor, Ryan C. McKellar, Luis M. Chiappe, Kuowei Tseng, Gang Li, Ming Bai published in Gondwana Research.