Titanis
Name Meaning: Titanic
Location Found: Florida (cast of original)
Size: 2.5 meters tall
Geographic range: American South (remains found in Florida and Texas)
Geologic Era: Pliocene-Pleistocene
Extinction: Roughly 1.8 million years ago
In many ways, Titanis and its kin, the phorusrhachids or terror birds, were throwbacks to the age of the dinosaurs. The age of mammals may have been well underway by the time Titanis and its kin came on the scene, but these successors to the theropod dinosaurs more than held their own for millions of years. While Titanis is still known from rather fragmentary remains, reconstructions based on more complete relatives show a formidable animal. The diagram shown below illustrates a 1.8 meter tall human (roughly 5’10”) compared to an average Titanis. For those who know me personally, I am only an inch shy of the human in the diagram. My skull would have easily cleared underneath the beak of Titanis with some room to spare.
The skull of Titanis gives us some clues as to its behavior. The areas of the brain devoted to smell were not terribly well developed, while those that were for visual centers and coordination were very well developed. The forebrain was also unusually large, indicating an animal that was not confined to acting in patterns. Taken together, these traits point to an animal that was an active hunter as opposed to a scavenger. Add these to the fact that the legs of Titanis were built for bursts of speed, what we see is an ideal combination for an ambush predator. Prey would have included anything smaller than Titanis, which would include many of the mammals it coexisted with, including horses of the time and deer.
The skull and neck of Titanis also give an idea as to the range of motion it was capable of. Side to side movement was somewhat limited, meaning Titanis was probably not shaking its prey back and forth like some modern mammals do. Forward and backwards motion, however, were very powerful. This meant that Titanis was more than capable of striking downward very forcefully with its beak. A strike to the skull from Titanis would probably result in instant death for a prey item.
Another aspect of behavior might be observed from the terror birds’ living relatives, the seriemas. Seriema birds dispatch prey by picking it up with their beaks and throwing it to the ground as hard as they can. This has the dual result of stunning/killing the prey, and also breaking bones, making the prey easier to swallow. What prey Titanis could not swallow whole was probably ripped apart using the unusually large middle claw on the hind legs.
The terror birds were not originally native to the North American continent. The lineage evolved in South America, and took advantage of the land bridge that formed between the two continents several million years ago to come to North America. Some North American mammals did the opposite, migrating south.
Overall, the animals that moved from north to south fared better than the ones who moved in the opposite direction. Titanis was an exception to this. It thrived for several million years in North America. Ultimately, however, it was unable to compete with new predators that had evolved, including wolves and bears. A similar scenario took place in South America, with the North American fauna out-competing the native animals.
Image Credits:
Scale to Human: http://www.prehistoric-wildlife.com/species/t/titanis.html
Skeleton: By Amanda from Chicago, USA – FlickrUploaded by FunkMonk, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=12044949
Life Reconstruction: By dmitrchel@mail.ru, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2991184