Spinosaurus and Africa's Lost River Giants: Inside Niza Ibrahim's Sahara Expeditions

Overview

In a conversation with New Scientist, palaeontologist Niza Ibrahim describes the hunt for Spinosaurus, a remarkable crocodile-jawed, sail-backed predator from Africa, and explains why the Sahara's Kemkem group fossils are transforming our understanding of dinosaur ecology.

He recounts the long, risky journey from childhood curiosity to field discoveries, the importance of Africa in the fossil record, and how modern methods including bone-density analysis and robotic tail models illuminate a semi-aquatic lifestyle for Spinosaurus. The interview also touches on science communication through media like Walking with Dinosaurs and the deep time perspective that links ancient life to human anatomy.

Spinosaurus and the Holy Grail

The interview centers on Spinosaurus, a giant, largely aquatic dinosaur with a slender croc-like jaw and an enormous sail formed by long neural spines. Described in 1915 and tragically destroyed during World War II, the skeleton has become a focal point for renewed discovery in Africa. Ibrahim describes how decades of searching, including a pivotal moment when a Moroccan fossil hunter leads them back to the dig site, culminated in a near-complete predatory dinosaur skeleton from mainland Africa. The find challenges decades of dinosaur dogma about terrestrial life and highlights Africa as a crucial, underrepresented region in paleontology.

African Expeditions and the Kemkem Group

Ibrahim outlines why Africa matters scientifically and culturally. The Kemkem plateau, near the Moroccan-Algerian border, preserves ~100-million-year-old rocks deposited in an ancient river system. This environment, described as a river of giants, featured vast rivers with diverse fish, crocodilians, turtles, and, at the river margins, dinosaurs. The site reveals a dense, predator-rich ecosystem that spanned wide swaths of the Sahara, illustrating a lost world far larger than modern deserts imply. The team faced harsh conditions, including sandstorms and isolation, yet uncovered thousands of fossils across multiple animal groups.

Spinosaurus: Anatomy, Adaptation, and Evidence

The Spinosaurus skeleton becomes more comprehensible through integrated evidence. A paddle-like tail and dense bones point to aquatic foraging, with conical teeth adapted to catching slippery prey. Ibrahim discusses collaboration with Harvard researchers to build a robotic tail model to compare Spinosaurus tail performance with other taxa, reinforcing the aquatic propulsion hypothesis. Another line of evidence comes from bone density analyses showing high buoyancy control similar to aquatic mammals and penguins, strengthening the case for a subaqueous lifestyle. The interview also covers the skull and snout adaptations, the paddle-tail reconstruction, and how these features contrast with earlier reconstructions in paleoart.

Methods, Challenges, and Interpretation

Scientists rely on comparative anatomy, digital reconstructions, and biomechanical modeling to infer behavior from fragmentary fossils. Ibrahim emphasizes caution: no living analogue perfectly matches Spinosaurus, so researchers triangulate data from multiple sources, including the extant phylogenetic bracket (crocs and birds) to infer soft-tissue and vocal capabilities. The team’s approach combines traditional anatomy with modern techniques such as finite element analysis and bone histology to estimate musculature, bite forces, and movement. The interview acknowledges ongoing debates within the field and how accumulating evidence gradually persuades the broader community.

Public Engagement and the Walk of Dinosaurs

Beyond science, the discussion highlights the role of paleontology in public understanding. Ibrahim reflects on the Walking with Dinosaurs series as a tool for science communication, advocating for portraying dinosaurs as complex, surviving lineages rather than fossilized failures. He notes that birds are still dinosaurs and that reconstructions in media should reflect deep-time continuity. The interview also touches on how media can bridge scientific discovery with curiosity, helping audiences grasp how science evolves with new evidence.

Looking Ahead: Fieldwork and Big Questions

The conversation ends with plans for future expeditions across Africa and beyond, including Romania and potential sites in the United States. Ibrahim is working on other iconic dinosaurs such as Triceratops and T. rex, highlighting the breadth of his fieldwork. He reflects on the human perspective, noting how deep-time thinking can illuminate modern anatomy and health, such as the spine’s S-curve and back pain, showing that the study of ancient life enriches our understanding of ourselves. The interview closes with an invitation to the next generation of palaeontologists to join in exploring the planet’s fossil riches.