Spinosaurus and the aquatic-dinosaur debate
A sail-backed giant that may have hunted in water
Quick facts
- When
- Late Cretaceous, about 99 to 94 million years ago
- Found in
- Egypt and Morocco
- Size
- About 14 m long (estimated; no complete skeleton found)
- Open debate
- Whether it actively swam and dove, or mainly waded near shore
What happened
Spinosaurus lived in what is now Egypt and Morocco in the Late Cretaceous, about 99 to 94 million years ago, and at an estimated 14 metres nose to tail, the Natural History Museum calls it longer than any other known carnivorous dinosaur, though it cautions that no complete skeleton exists, so the full length is an estimate. It carried a sail on its back roughly 1.5 metres tall whose purpose is itself unresolved, possibly for temperature regulation, display, or swimming. Fossils show short hind legs and a wide, paddle-like tail, and the museum states outright that whether Spinosaurus actively swam and hunted underwater, or mostly waded and struck from the shoreline, is not settled. A 2022 Natural History Museum report on new supporting evidence still carried on-the-record pushback from outside researchers: Dr David Hone of Queen Mary University of London said the new findings did not resolve doubts about whether the animal could truly dive and swim, even if dense bones let it wade in deeper water.
Why it matters
Spinosaurus is the sharpest live scientific argument in this timeline. Whichever way the debate eventually settles, it shows that even a dinosaur famous enough to appear in blockbuster films still has open questions that working paleontologists actively disagree about in print.
How we know
The Natural History Museum's Dino Directory entry gives Spinosaurus's age, location, estimated length with its own caveat about incompleteness, its sail, and states plainly that its aquatic lifestyle is unclear. A 2022 museum news report adds an on-the-record skeptical view from an outside expert, so this event's confidence reflects a genuinely open scientific question, not settled fact.
Sources
- Natural History Museum, London. Spinosaurus (Natural History Museum Dino Directory) (2024) · Reputable sourcenhm.ac.uk · The domain "nhm.ac.uk" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- Natural History Museum, London. Spinosaurus and Baryonyx may have hunted fish underwater (Natural History Museum news, March 2022) (2022) · Reputable sourcenhm.ac.uk · The domain "nhm.ac.uk" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- Ibrahim et al.. Tail-propelled aquatic locomotion in a theropod dinosaur [Spinosaurus] (Nature, 2020, via PubMed) (2020) · Peer-reviewed (author-declared)pubmed.ncbi.nlm.nih.gov · Cited as a "journal" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
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