Ecological restoration diagram of the pseudo-toothed bird
Fossil specimen of pseudolodon
Recently, fossils from Antarctica 50 million years ago were identified as an extinct giant pelagic bird, the pseudolodon. The record of this discovery is the earliest fossil record of giant flying birds. The results were published in Scientific Reports on October 26 by scientists at the University of California, Berkeley, and the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences.
Pseudoodonts are noticeable for their special "bone teeth", which have unique bone spurs on their jaws, like a mouth full of fangs. The paper published a study of a fossil of a pseudolodon found on Seymour Island in Antarctica, which may be the largest bird ever able to fly. The fossil is currently preserved in the University of California Paleontological Museum as a broken jaw about 12 cm long.
It is worth noting that the bone "teeth" retained on the jaw may be up to 3 cm long when the pseudo-toothed bird is alive, and this broken jaw may originate from a skull up to 60 cm long. Through measurements of the size and spacing of these "teeth", as well as analysis of comparisons with other pseudolodon fossils, this individual is larger than or approximately the largest pseudolodated bird specimen known to date. The authors, combined with metatarsal fossils from another fossil site on the island, speculate that the wingspan of extinct species represented by fossils is between 5 and 6 meters.
The fossil points found were first discovered by the Antarctic expedition, and through the original field records, it was found that the metatarsal fossils were produced in a fossil point 50 million years ago, while the jaw fossils came from a fossil point 40 million years ago.
Author Peter Cross said: "Today the ostrich is the largest non-flying bird, and the diomedea exulans with a wingspan of nearly 3.5 meters is the largest flying bird. However, the discovery of the pseudolodon bird has a wingspan of between 5 and 6 meters, indicating that birds evolved very rapidly after the extinction of the dinosaurs, and the long time interval between the two fossil points of 10 million years indicates that this giant bird dominated the sky over the ocean for tens of millions of years. ”
Study co-author Dr Ashley said: "The sheer size of these extinct birds is unmatched in marine habitats. Only one bird closely related to the vulture, the teratornis, could match the wingspan, but they did not appear until 40 million years after the pseudolodon became extinct. ”
Co-author Thomas, a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences, explains that the pseudolodont survival strategy found may be close to that of albatrosses, which also have huge wingspans. Antarctic waters are now dominated by whales and seals, but back then, the giant pseudolodon soared through the open sea in search of its prey, squid and fish, and its iconic sharp "dentures" made it the dreaded ruler of Antarctic waters.
In the Eocene 50 million years ago, Antarctica's climate was much warmer than it is today, not the daunting icy continent we know today. At that time, in addition to mammals such as marsupials, sloths and distant relatives of anteaters, birds occupied the sea, land and sea of the Antarctic continent, and were a paradise for ducks, ostriches, petrels, and many extinct relatives of birds. The giant pseudolodon is also part of this Antarctic ecosystem, living in Antarctica for at least 10 million years. (Cui Xueqin)
Related thesis information: https://www.nature.com/articles/s41598-020-75248-6
Source: China Science Daily