A fossil collected in Antarctica in 1985 was recently identified as the first dinosaur bone ever found on the continent—a tail vertebra from a titanosaur sauropod.

Geologist Mike Thomson found the fossil on James Ross Island (Antarctic Peninsula) on December 9, 1985, during a British Antarctic Survey expedition. It was initially logged as possibly from a large reptile but remained unstudied in a drawer at the British Antarctic Survey’s collection for about 40 years.

In 2026, palaeontologist Dr. Mark Evans (in collaboration with the Natural History Museum in London) re-examined it and confirmed it as a dinosaur bone. The formal description was published on June 29, 2026, in Acta Palaeontologica Polonica.

It’s an 82-million-year-old (Late Cretaceous, lower Campanian) caudal (tail) vertebra from a titanosaurian sauropod. Titanosaurs were long-necked, plant-eating dinosaurs, some of the largest land animals ever. This specimen likely came from a relatively small or young individual, estimated at 6–7 meters long.

This find predates other Antarctic dinosaur discoveries, such as Antarctopelta (an ankylosaur found in 1986 on the same island), which had previously been considered among the earliest. Earlier dinosaur fossils were later found elsewhere in Antarctica (e.g., Transantarctic Mountains in the early 1990s), but this was the first one collected.

It provides evidence that sauropods lived in what is now Antarctica during a time when the continent was much warmer and forested, supporting ideas about dinosaur dispersal across southern continents (Gondwana).

Antarctica was a dramatically different place during the Late Cretaceous.

Paleogeography

In the Late Cretaceous (roughly 100–66 million years ago), Antarctica was part of the southern supercontinent Gondwana (or its remnants). It remained connected—or had relatively recent connections—to South America, Australia, and other southern landmasses. This allowed dinosaurs and plants to disperse across what are now widely separated continents. Antarctica sat at high southern latitudes (near the South Pole, similar to today), but global “greenhouse” conditions made it habitable.

Climate and Vegetation

Temperate to subtropical conditions:

High-latitude summers were warm (averaging around 20°C or more during thermal maxima), with adequate moisture. Winters were cooler and dark (due to polar nights), but evidence suggests temperatures rarely dropped far below freezing for extended periods in many areas, supporting lush vegetation.

Forests:

Polar forests thrived, dominated by:

• Conifers (e.g., araucarian “monkey puzzle” types and podocarps).
• Ferns (common in the understory).
• Angiosperms (flowering plants, including early forms that diversified rapidly).
• Other elements like cycads, ginkgos, and later southern beeches (Nothofagus).

These created mixed evergreen and deciduous forests, with evidence of river systems, floodplains, and high rainfall. Fossil leaves, wood, pollen, and charcoal from sites like the Antarctic Peninsula (e.g., James Ross Island area, where the titanosaur vertebra was found) paint this picture.

The Santa Marta Formation (where this fossil originates) reflects a coastal or near-shore environment with such vegetation around 82–80 million years ago (lower Campanian).

Transition to Ice

This warm phase was part of the broader Cretaceous greenhouse world. Cooling began toward the end of the Cretaceous and accelerated in the Cenozoic, leading to the Antarctic ice sheets we see today (starting significantly around 34 million years ago). By the Neogene, the vegetation shifted toward more cold-tolerant forms before glaciers dominated.

This environment explains why dinosaurs like the titanosaur (and others, such as hadrosaurs and ankylosaurs found later) could live there—plenty of plant food in a forested landscape, despite the high latitude and seasonal light variations. Polar forests were a real feature of Cretaceous high latitudes in both hemispheres, though Antarctic ones leaned more evergreen.

The recent re-identification of that 1985 fossil adds a nice data point to this story, showing sauropods inhabited these southern high-latitude ecosystems.

Supercontinent Gondwana

Gondwana (also called Gondwanaland) was a massive southern supercontinent that played a central role in the story of Antarctica, its dinosaurs, and its ancient forests.

Gondwana assembled from earlier continental fragments through collisions in the Late Precambrian to Early Paleozoic (around 600–500 million years ago). It included what are now:

• South America
• Africa (plus Arabia)
• Antarctica
• Australia
• India
• Madagascar
• And other smaller landmasses

At its peak, it covered a huge portion of Earth’s surface. It later fused with the northern supercontinent Laurasia to form the even larger Pangaea around 300 million years ago (Carboniferous-Permian).

Gondwana began breaking apart in stages:

• Early Jurassic (~180 million years ago) — Initial rifting separated western (Africa-South America) and eastern sections.
• Cretaceous Period — Key separations accelerated. By the Late Cretaceous (the time of the titanosaur fossil ~82 million years ago), the southern continents were still closer together than today but actively drifting.
  • South America and Africa had mostly separated (opening the South Atlantic).
  • Antarctica remained connected (or had land bridges/connections) to South America (via the Antarctic Peninsula region) and Australia.
  • India had rifted away and was drifting northward.
  • This created a “Weddellian” biogeographic province linking southern South America, Antarctica, and parts of Australia/New Zealand, explaining similarities in dinosaur faunas (e.g., titanosaurs, hadrosaurs).

The final major separations (e.g., full isolation of Antarctica from South America via the Drake Passage and from Australia) occurred later, in the Paleogene (after ~66 million years ago), contributing to the development of the Antarctic Circumpolar Current and eventual glaciation.

Land connections allowed dinosaurs (like titanosaurs) and plants (ferns, conifers, early flowering plants) to move between what became separate continents. This is why we see related fossils in Patagonia (South America) and Antarctica.

Gondwana’s southern position placed Antarctica near the South Pole, yet warm global climates and connections supported temperate/polar forests rather than ice.

Late Cretaceous Gondwanan dinosaurs often differed from Laurasian ones: titanosaurs were major herbivores in the south, while abelisaurid predators were common (versus tyrannosaurs in the north).

In short, the Late Cretaceous Antarctic titanosaur lived on a fragment of a still-disassembling Gondwana—a greener, connected world very different from today’s isolated, frozen continent.