In Depth Although Procariama was one of the famous South American ‘terror birds’ it was actually one of the smallest being of a comparable size to Psilopterus and Paleopsilopterus, the other members of the Psilopterinae sub group. As such Procariama would have had a focus upon smaller prey animals that were too small for the … Read more
In Depth Mesembriornis was a middle of the range ‘terror bird’ with regards to its size, but it was one of the last known to have lived. In overall build Mesembriornis was similar to other medium sized phorusrhacids such as Andalgalornis and may have also filled the same ecological niche as its earlier predecessor. Mesembriornis … Read more
In Depth Patagornis was the first of the Patagornithinae sub group of the phorusrhacid ‘terror birds’, and as such it was more intermediate in size. This would mean that Patagornis had no way near the size and strength of the larger members of the group, but they would have been much faster and more agile. … Read more
In Depth As a member of the Brontornithinae group of terror birds Physornis was one of the larger and more robust members of the larger group, the Phorusrhacidae. As such it would have been related to Paraphysornis and Brontornis, and living during the Oligocene it was one of the earliest terror birds to roam and … Read more
In Depth Paraphysornis was one of the more robust members of the phorusrhacid ‘terror birds’ and was most closely related to Physornis and Brontornis. Because of its large size and heavier build, Paraphysornis probably relied more upon ambush tactics to surprise prey rather than running it down over extended distances. Although this does not mean … Read more
In Depth Like similar predatory birds of its day, Phorusrhacos was flightless with its wings greatly reduced in size. The wings of Phorusrhacos also had sharp hooks that seem to be more suited for gripping. These hooks have been suggested as being used to secure struggling prey as Phorusrhacos dispatched it with its beak, but … Read more
In Depth Brontornis was easily one of the largest of the known South American ‘terror birds’, and as a member of the Brontornithinae it is noted as being one of the most robust in build. Whereas some terror birds could use their speed to run down prey, Brontornis would have been more suited to ambush … Read more
In Depth Andalgalornis has a more gracile build than many other South American ‘terror birds’ and this lightweight build is also reflected in the skull and beak. In depth analysis suggests that the beak was strongest when subjected to stresses from below rather than the sides. This meant that gripping and holding large prey was … Read more
In Depth Being one of the smallest members of the Phorusrhacidae, Psilopterus was no way near the scale of the larger phorusrhacids like Brontornis. However the exact size of Psilopterus is something that is hard to be certain about as not only do estimates depend upon the specific species, but there is an outside chance … Read more
Large flightless birds are well known in the fossil records of the world’s southern continents, but it is usually the ‘terror birds’ of the Phorusrhacidae that usually steal the thunder of the others. Titanis manages to stand out from these other terror birds, not because it was one of the largest or most terrifying, but … Read more