This page compares the succession of Mesozoic apex predators across four continents. The question is simple: who occupied the large-predator niche, in each region, over roughly 110 million years? The answer varies more than one might expect.
The four figures below use the same visual format (silhouettes plus stratigraphic bands plus species markers, inspired by Zanno and Makovicky 2013) to make the comparison direct. In some cases there was strict succession between dominant clades; in others, prolonged coexistence; in all of them, the large-predator fauna was rewritten by the Cenomanian-Turonian extinctions (around 90 Ma).
Figure 1, North America
Classic three-phase succession
The North American pattern is the textbook case of Mesozoic apex-predator succession. Three almost strictly sequential phases: basal allosauroids in the Late Jurassic (Allosaurus, Saurophaganax, Torvosaurus), giant carcharodontosaurians in the Middle Cretaceous (Acrocanthosaurus, Siats), and tyrannosaurids in the last 20 million years or so of the Cretaceous (Lythronax, Daspletosaurus, Albertosaurus, Tyrannosaurus). Like Eoabelisaurus in South America, the tyrannosaurid lineage already existed at small body size since the Late Jurassic (Stokesosaurus, in the Morrison Formation), preceding its period of dominance by nearly 80 million years.
Figure 1. Three successive phases in the North American Mesozoic. In the Late Jurassic (about 156 to 145 Ma, Morrison Formation), large allosauroids such as Allosaurus, Saurophaganax, Torvosaurus and Ceratosaurus dominated the apex-predator niche. Stokesosaurus, a small tyrannosauroid, already existed during the same period: it is the oldest known tyrannosauroid, preceding the reign of tyrannosaurids by nearly 80 million years. In the Middle Cretaceous (about 115 to 95 Ma), carcharodontosaurians took over (Acrocanthosaurus in the Aptian-Albian, Siats in the Cenomanian), while small tyrannosauroids such as Suskityrannus and Moros survived as mesopredators. After the carcharodontosaurians went extinct at the end of the Turonian (about 90 Ma), tyrannosaurids quickly seized the top in the Campanian and Maastrichtian (Lythronax, Daspletosaurus, Gorgosaurus, Albertosaurus, Tyrannosaurus rex). Reconstruction adapted from Zanno and Makovicky 2013, Nature Communications.
Figure 2, South America
Same plot, different final villain
South America follows the same succession model up to the end of the Turonian (around 90 Ma), but what replaces the carcharodontosaurids is not tyrannosaurids: it is abelisaurids. This lineage already existed at small body size in Patagonia since the Middle Jurassic (Eoabelisaurus, ~178 Ma), preceding its period of dominance by nearly 100 million years. Tyrannosaurids never reached the Southern Hemisphere.
Figure 2. Mesozoic terrestrial apex predators of South America. In the Middle Jurassic (178 to 165 Ma, Cañadón Asfalto Formation, Patagonia), the large-predator niche was occupied by basal tetanurans: allosauroids such as Asfaltovenator (~7-8 m) and piatnitzkysaurids such as Piatnitzkysaurus and Condorraptor. Eoabelisaurus, the oldest known abelisauroid, also dates from this period, still at small body size. The South American Early Cretaceous and Late Jurassic have a sparse record. In the Aptian-Cenomanian (125 to 94 Ma) carcharodontosaurids dominated (Tyrannotitan, Giganotosaurus, Mapusaurus, Meraxes). After 90 Ma, abelisaurids took over (Abelisaurus, Aucasaurus, Carnotaurus, Niebla, Llukalkan). Tyrannosaurids never established themselves in the Southern Hemisphere.
Figure 3, Asia
Same model, late tyrannosaurid rise
Asia follows the same Zanno model (three-phase succession), but with an important difference: the rise of tyrannosaurids into the large-predator niche was late, occurring only after the Turonian (around 90 Ma). Before that, they were small mesopredators coexisting with giant carcharodontosaurians such as Ulughbegsaurus, in Uzbekistan. Only in the Campanian and Maastrichtian did tyrannosaurids reach gigantic size with Tarbosaurus, Zhuchengtyrannus and Qianzhousaurus.
Figure 3. Three successive phases in the Asian Mesozoic. In the Late Jurassic (165 to 145 Ma), large allosauroids such as Sinraptor and Yangchuanosaurus dominated China. In the Middle Cretaceous (125 to 90 Ma), carcharodontosaurids took over (Datanglong, Kelmayisaurus, Shaochilong, Ulughbegsaurus). Tyrannosaurids only rose to the top after the Turonian. Early on, tyrannosauroids such as Timurlengia were small mesopredators coexisting with Ulughbegsaurus; only in the Campanian and Maastrichtian did they reach gigantic size (Tarbosaurus, Zhuchengtyrannus, Qianzhousaurus).
Figure 4, Africa
Multi-clade coexistence instead of succession
Africa is structurally different from the three previous regions. Instead of strict succession, there is multi-clade coexistence in the Middle Cretaceous: three groups of large predators (carcharodontosaurids, spinosaurids and abelisaurids) occupied the same environment simultaneously, with ecological prey partitioning. The peak is in the Kem Kem fauna (Morocco, ~95 Ma), where Carcharodontosaurus, Spinosaurus and Rugops lived together. After the first two groups went extinct at the end of the Cenomanian-Turonian, only the abelisaurids remained.
Figure 4. Multi-clade coexistence in the African Mesozoic. In the Late Jurassic (~152 Ma, Tendaguru, Tanzania), Veterupristisaurus was already a large basal carcharodontosaurian. In the Aptian-Albian (~125-100 Ma, Niger), three clades coexisted: carcharodontosaurids (Eocarcharia), spinosaurids (Suchomimus) and small abelisaurids (Kryptops). The peak occurred in the Cenomanian (~95 Ma) with the Kem Kem fauna (Morocco): Carcharodontosaurus, Spinosaurus, Sigilmassasaurus, Bahariasaurus, Deltadromeus and Rugops simultaneously. After the carcharodontosaurids and spinosaurids went extinct at the end of the Cenomanian-Turonian, only the abelisaurids remained (Majungasaurus in Madagascar, Chenanisaurus in Morocco). The African Coniacian-Santonian record is fragmentary.
Main sources.
Zanno and Makovicky (2013, Nature Communications) for the North American pattern and the model design.
Tanaka et al. (2021, Royal Society Open Science) on Ulughbegsaurus and the late rise of tyrannosaurids in Asia.
Pol and Rauhut (2012, Proc. R. Soc. B) on Eoabelisaurus and the early origin of abelisauroids in Patagonia.
Rauhut and Pol (2019, Scientific Reports) on Asfaltovenator.
Sereno et al. and Hassler et al. (2018) on ecological partitioning of Kem Kem via calcium isotopes.
Silhouettes: PhyloPic (Tasman Dixon, Scott Hartman, Fred Wierum, Connor Ashbridge, Jagged Fang Designs, all CC BY).
