A newly identified 127 million-year-old extinct bird species has revealed a crucial evolutionary stepping stone between ancient dinosaurs and modern birds.
The fossil, which was unearthed in northeastern China, provides new information about avian development during the early evolution of flight.
The early Cretaceous fossil dates to a time when birds had already lost their long bony tail, but before they evolved a fan of flight feathers on their shortened tail.
The fossil (left) was found in northeastern China and provides new information about avian development during the early evolution of flight. The scientists named this well-preserved complete skeleton Jinguofortis perplexus (artist’s impression, right)
Scientists from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences have named the well-preserved complete fossil Jinguofortis perplexus.
Jinguofortis is an amalgamation of the Chinese word ‘jinguo’, which means female warrior, and the Latin word ‘fortis’, meaning brave.
The latest findings were published in the Proceedings of the National Academy of Sciences.
According to the researchers, Jinguofortis perplexus had a unique combination of traits, including a jaw with small teeth – like its theropod dinosaur relatives (a suborder of dinosaurs characterised by their hollow bones and three-toed limbs).
The two-legged theropod dinosaurs, such as Tyrannosaurus rex also had bird-like feet, a bird-like pelvis, and a ‘wishbone’ typical of birds.
Like birds, they also had hollow bones that may have contained air sacs used in breathing.
The new specimen had evolved a bird-like short bony tail ending in a compound bone called a pygostyle.
Stones found in its gizzard reveal that it mostly ate plants and also had a third finger with only two bones, unlike other early birds.
The fossil’s shoulder joint also gives clues about its flight capacity.
In flying birds, the shoulder, which experiences high stress during flight, is a tight joint between unfused bones.
In contrast, Jinguofortis’s shoulder bones are fused to one another.
Based on its skeleton and feathers, Jinguofortis perplexus probably flew a bit differently than birds do today.
Measurement of the fossil’s wing size and estimation of its body mass show that the extinct species had a wing shape and wing-to-body ratio similar to living birds.
Pictured are the major changes of the coracoid and scapula (main components of the shoulder girdle) across the major vertebrate groups. In flying birds, the shoulder, which experiences high stress during flight, is a tight joint between unfused bones
This latest find follows research from last month that revealed dinosaur DNA is the same as modern birds.
The ancient reptiles may have come in such different shapes and sizes because their genetic code had ‘a large number’ of chromosomes, scientists found.
This diversity helped them evolve quickly to changing climates, allowing them to dominate the planet for around 180 million years.
Using DNA from modern-day turtles and birds, researchers were able to piece together the history of DNA back more than 255 million years.
Scientists believe the way their DNA was organised may have provided dinosaurs with a ‘blueprint for evolutionary success’.
Researchers led by Professor Darren Griffin of the University of Kent’s School of Biosciences recreated what the genome structure of dinosaurs would have looked like under the microscope.
‘Having a lot of chromosomes enables dinosaurs to shuffle their genes around much more than other types of animals’, Professor Griffin told BBC.
‘This shuffling means that dinosaurs can evolve more quickly and so help them survive so long as the planet changed,’ he said.