When the paleontologists first plucked a massive, scimitar-shaped bone from the desolate sands of the central Sahara in 2019, they didn’t immediately recognize it for what it was.\u00a0<\/p>\n
It took a return expedition, two more crests and a 3D digital skull assembly powered by solar panels in the middle of the desert in Niger before the realization sank in\u2014they\u2019d unearthed the towering head crest of an entirely new species of dinosaur.<\/p>\n
“This find was so sudden and amazing, it was really emotional for our team,” said Paul Sereno, professor of organismal biology and anatomy at the University of Chicago, who led the 20-person group. “I’ll forever cherish the moment in camp when we crowded around a laptop to look at the new species for the first time.”<\/p>\n
A new paper published in Science<\/a> describes their journeys in 2019 and 2022 to find Spinosaurus mirabilis, the first new spinosaurid species discovered in more than a century.\u00a0<\/p>\n A large, fish-eating predator, S. mirabilis adds important new fossil finds to the closing chapter of its genus\u2019s evolution. Based on the crest\u2019s surface texture and interior vascular canals, the experts believe it was sheathed in keratin and brightly colored in life, curving toward the sky as a blade-shaped beacon.<\/p>\n Another striking feature of the skull is its interlocking teeth, where those of the lower jaw protrude outward and between those of the uppers to make a deadly trap for slippery fish. This is a common adaptation among fish-eaters in the fossil record\u2014including aquatic ichthyosaurs, semi-aquatic crocodiles and airborne pterosaurs. Among dinosaurs, it sets Spinosaurus and closest kin apart.\u00a0<\/p>\n Before, spinosaurid bones and teeth had been found mainly in coastal deposits not far from the shoreline, leading some experts to hypothesize that these fish-eating theropods may have been fully aquatic, pursuing prey underwater.<\/p>\n However, the new fossil area in Niger documents animals that were living inland, some as far as about 620 miles from the nearest marine shoreline. Their proximity to intact partial skeletons of long-necked dinosaurs, all buried in river sediments, suggests they lived in a forested inland habitat dissected by rivers.<\/p>\n \u201cI envision this dinosaur as a kind of \u2018hell heron\u2019 that had no problem wading on its sturdy legs into two meters of water but probably spent most of its time stalking shallower traps for the many large fish of the day,\u201d Sereno said.<\/p>\n A remarkable expedition to Niger<\/p>\n The journey that culminated in this discovery started with a single sentence in a monograph from the 1950s, where a French geologist mentioned finding a single saber-shaped fossilized tooth resembling those of the giant predator Carcharodontosaurus\u00a0found in Egypt\u2019s Western Desert at the turn of the last century.\u00a0<\/p>\n \u201cNo one had been back to that tooth site in over 70 years,\u201d Sereno mused. \u201cIt was an adventure and a half wandering into the sand seas to search for this locale and then find an even more remote fossil area with the new species. Now all of the young scholars who joined me are co-authors on the report gracing the cover of Science.\u201d<\/p>\n The team ended up meeting a local Tuareg man who led them on his motorbike deep into the center of the Sahara, where he had seen huge fossil bones. After nearly a full day of travel with no shortage of doubts regarding the success of the effort, he led them to a fossil field. There, with little time to spare before returning to camp, the team found teeth and jaw bones of the new species of Spinosaurus.<\/p>\n Sereno has excavated more than 100 tons of fossil finds in the Sahara over the past 30 years\u2014much of which have added to Niger\u2019s rich legacy in paleontology and archaeology. He has also led an international award-winning effort to build the world\u2019s first zero-energy museum, the Museum of the River<\/a>, on an island in the center of Niger\u2019s capital city of Niamey.<\/p>\n This facility will showcase the country\u2019s world-class patrimony that documents Africa\u2019s lost world of dinosaurs, now including an astonishing spinosaur species, as well as stone-age cultures that once lived in a green, humid Sahara.<\/p>\n \u201cThe local people we work with are my lifelong friends, now including the man who led us to Jenguebi and the astonishing spinosaur. They understand the importance of what we\u2019re doing together\u2014for science and for their country,\u201d Sereno said.<\/p>\n Bringing Spinosaurus mirabilis to the world<\/p>\n Back home in Chicago, Sereno\u2019s team at his South Side Fossil Lab<\/a> in Washington Park cleaned and then CT scanned the teeth and bones, assembling a digital skull rendering for the research report. Using that rendering, Sereno worked with paleoartist Dani Navarro in Madrid to create an action scene involving flesh reconstructions of the new species tussling over a coelacanth carcass. Navarro went farther, creating a detailed 3D physical model of S. mirabilis by adding flesh over a skeletal reconstruction.\u00a0<\/p>\n Other paleoartists\u2014Jonathan Metzger in Chicago and Davide la Torre in Italy\u2014animated Navarro\u2019s model, bringing to life the scene chosen for the cover of Science.\u00a0<\/p>\n As part of these reconstruction efforts, the team also prepared a replica of the newly discovered skull and a touchable, colorful model of the scimitar crest.\u00a0<\/p>\n On March 1, in the wake of the Science paper, both replicas will join Sereno\u2019s previous Dinosaur Expedition<\/a> exhibit at the Chicago Children\u2019s Museum, where young learners will be among the first to see this latest dinosaur find.<\/p>\n \u201cLetting kids feel the excitement of new discoveries\u2014that\u2019s key to ensuring the next generation of scientists who will discover many more things about our precious planet worth preserving,\u201d Sereno said.<\/p>\n