These flightless birds were 11 feet tall and weighed nearly half a ton at an estimated 450 kilograms. For context: the ostrich is he largest bird on earth and adult ostriches weigh just 150 kilos (330 lbs).
The Pachystruthio dmanisensis was discovered using a femur bone found in 2018 on the Crimean Peninsula, in the northern Black Sea. Based on other animal remains found in the same cave this particular dmanisensis is estimated to have died between 1.5 and 2 million years ago. That puts it at the right time to have been around when the first humans migrated to the area!
In 2018, paleontologists examined the fossil of a bird which had been discovered in northwest China a few years earlier. The new species, Avimaia schweitzerae, was around 115 million years old. In a fossil first, the bird was pregnant with an egg. But there was something wrong with the egg. It had too many layers – as many as six layers in some places. Scientists think this could be why the bird died. In modern birds, trauma can delay a female from nesting, and she can keep an egg inside herself for too long. Over time, her body adds unnecessary layers of shell around it. Known as “egg binding,” it smothers the embryo and often kills the mother.
But that was not the only surprise Avimaia schweitzerae had in store. When a bird prepares for egg-making, she stacks up on calcium in the medullary bone — something that has never been positively identified in a fossil bird before. Avimaia’s medullary region showed all the right signs. If confirmed, it would provide a unique link between avian reproduction and this bone.
The earliest fossilized lungs have been found in an ancestral bird species. About 120 million years years ago, the Archaeorhynchus spathula lived in what is today China alongside dinosaurs, before dying in a volcanic eruption. The newfound fossil is unusual for its preserved feathers and considerable soft tissue, which show that this primitive bird’s lungs closely resemble those found in living birds.
Modern birds have hyper-efficient lungs. Flying is a tough workout, and hyper-efficient lungs process oxygen quickly and with less effort, so that birds’ muscles can get enough oxygen during flight to keep going. This new fossil suggests such specialized lungs evolved earlier than previously thought.