Giganotosaurus carolinii JIG-uh-NOTE-oh-SOR-us

"Giant southern lizard"

Giganotosaurus silhouette
You 1.8 m (5.9 ft) tall
Giganotosaurus 13 m (41 ft) long
8 people holding hands
silhouette · Ivan Iofrida (CC-BY) via PhyloPic
Length
13 m (41 ft) — About 12.5 m long, ~7 tonnes — slightly longer than T. rex.
Period
Late Cretaceous (99–97 Mya)
Place
South America · Argentina
Food
Carnivore — Large prey — possibly the giant titanosaur sauropods that lived alongside it.
Clade
Allosauroidea Dinosauria Saurischia Theropoda

Giganotosaurus rivaled Tyrannosaurus rex in size — possibly even longer, though probably lighter. It lived 30 million years before T. rex on a different continent, hunting giant sauropods across what is now Patagonia. Its discovery in 1993 dethroned T. rex as the biggest carnivore, though new finds keep reshuffling the list.

What we know

  • Skull longer than T. rex but more lightly built — about 1.6 m long.
  • Closely related to Carcharodontosaurus and Mapusaurus — the carcharodontosaur family.
  • Lived alongside the giant sauropod Andesaurus.
  • Multiple individuals found together at one site, possibly a pack.

What we guess

  • Whether Giganotosaurus or T. rex was heavier — estimates put both close to 7–8 tonnes.
  • Whether the multiple-individual site is real pack evidence or just multiple deaths over time.
  • How it brought down adult titanosaurs — slashing bites and exhaustion are the leading ideas.