When the dinosaurs became extinct, a hole remained in the trophic chain. The mega-predators disappeared, equivalent to the lions, tigers or wolves of today. Some mammals and reptiles competed in the highest levels of this chain, but in some places it was the non-flying birds that reigned and subdued the rest of living beings.
It is a group of birds with no current equivalent. Its presence is documented on all continents except Antarctica, but like its predecessors, the dinosaurs also became extinct.
The skull in all cases stands out for its large size; the very robust and sharp corneal beak adapted to consume meat. Presumably they ate carrion, but their hind legs: long and muscular, and their body: not very heavy; They provided these birds with speed in the race, perfect for chasing their prey.
Gastornis, was one of the pioneers. Its presence in Europe is documented 56 million years ago. In his "world" he was a giant, who was supposed to keep the small mammals that then populated Germany frightened. But the debate about his diet has officially begun. Until a few years ago it was considered carnivorous, but in 2014 a study appeared that seems to indicate the opposite.
Skull of Gastornis
The shape of its beak is different from that of most "birds of terror", and the size of the muscles of the jaw fits more with a bird that eats seeds. It is true that the study is not conclusive, although the doubt about its feeding is reasonable.
The same happens with the Dromornis of Australia. In both cases, in its ecosystem there were plants that provided large seeds, which perhaps could have consumed by this type of bird.
There is no doubt, however, with the Kelenken, one of the largest "birds of terror", and not with the predatory habits of Titanis. The huge skull scares and the curved beak fits with that of a carnivore. The surprising thing of the Titanis are its wings, similar to "arms", since in its ends it had hands provided with two sharp claws similar to those of the Tyrannosaurus rex.
Skull of Titanis
The evolutionary line of this set of birds is not clear. Presumably, a group of medium sized dinosaurs could give rise to this type of animals. Titanis lived 5 million years ago and is one of those last birds of terror. Mammals with more variability won the game and now dominate the land. The question is: Will the birds of terror return? o What other creatures does evolution provide?
Terror bird´s sizes
Germán Z. López
This post can also be read in Spanish at our partner blog Made in Pangea.
- Isotopic and anatomical evidence of an herbivorous diet in the Early Tertiary giant bird Gastornis. Implications for the structure of Paleocene terrestrial ecosystems. Naturwissenchaffen. 101(4), 313-322. Angst, D., Lécuyer, C., Amiot, R., Buffetaut, E., Fourel, F., Martineau, F., Legendre, S., Abourachid, A. & Herrel, A. (2014).