{"id":14788,"date":"2025-06-09T22:00:00","date_gmt":"2025-06-09T22:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=14788"},"modified":"2025-06-05T04:05:51","modified_gmt":"2025-06-05T04:05:51","slug":"spinosaurus-century-shifting-paradigms-paleontology-june-2025","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/spinosaurus-century-shifting-paradigms-paleontology-june-2025\/","title":{"rendered":"Spinosaurus: A Century of Shifting Paradigms in Paleontology"},"content":{"rendered":"\n<div class=\"wp-block-group has-gray-200-background-color has-background\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<h1 id=\"at-a-glance\" class=\"wp-block-heading\">At a Glance<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"\"><em>Spinosaurus<\/em>, a massive sail-backed predator from Late Cretaceous North Africa, has long fascinated scientists due to its unusual anatomy, especially its debated aquatic adaptations and locomotion style.<\/li>\n\n\n\n<li class=\"\">Initially discovered in Egypt in 1912 and destroyed in World War II, the holotype\u2019s loss left paleontologists reliant on drawings and new fragmentary fossils that have sparked continuous reinterpretation of the species.<\/li>\n\n\n\n<li class=\"\">Discoveries in the 2000s and 2010s suggested <em>Spinosaurus <\/em>had short hind limbs and a paddle-like tail, indicating potential aquatic behavior, though later studies questioned its ability to dive or swim effectively.<\/li>\n\n\n\n<li class=\"\">Multiple studies, including recent ones from 2022 to 2024, suggest <em>Spinosaurus<\/em> may have been a shoreline predator with heron-like behavior, while others defend the aquatic hypothesis using tail structure and bone density.<\/li>\n\n\n\n<li class=\"\">Debates also persist over its species identity, geographic range, and locomotion. Recent evidence supports a \u201cgraviportal biped\u201d model and distinct African and South American spinosaurid lineages.<\/li>\n<\/ul>\n<\/div><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"\">Few of the giant predatory dinosaurs that once roamed Earth have captivated scientists and the public, like <em>Spinosaurus<\/em>. This massive theropod\u2014a group of typically bipedal (two-legged) carnivorous dinosaurs\u2014often depicted with a striking sail on its back, was a formidable carnivore that lived in what is now North Africa during the Cenomanian stage of the Late Cretaceous period, approximately 100 to 94 million years ago. For decades, <em>Spinosaurus<\/em> has been a subject of intense scientific scrutiny, with its unique anatomy leading to continuous debates about its size, locomotion, and, most famously, its relationship with water. Even today, new research keeps challenging old assumptions, making <em>Spinosaurus<\/em> one of the most contentious and fascinating topics in paleontology.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This skeletal reconstruction of Spinosaurus in a museum exhibit highlights its unique features, including the distinctive sail on its back, crocodile-like snout, and powerful forelimbs. Such reconstructions are constantly updated as new fossil discoveries reshape our understanding of this enigmatic dinosaur. (&quot;Spinosaurus - 02&quot; by\u00a0Kabacchi\u00a0is licensed under\u00a0CC BY 2.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/live.staticflickr.com\/2795\/4078770583_4cc9d59f6c_o.jpg\" ><figcaption class=\"wp-element-caption\">This skeletal reconstruction of <em>Spinosaurus<\/em> in a museum exhibit highlights its unique features, including the distinctive sail on its back, crocodile-like snout, and powerful forelimbs. Such reconstructions are constantly updated as new fossil discoveries reshape our understanding of this enigmatic dinosaur. (&#8220;<a href=\"https:\/\/www.flickr.com\/photos\/36197880@N03\/4078770583\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus &#8211; 02<\/a>&#8221; by\u00a0<a href=\"https:\/\/www.flickr.com\/photos\/36197880@N03\" target=\"_blank\" rel=\"noreferrer noopener\">Kabacchi<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY 2.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h1 id=\"a-fleeting-discovery\" class=\"wp-block-heading\">A Fleeting Discovery<\/h1>\n\n\n\n<p class=\"\">The story of <em>Spinosaurus<\/em> began in 1912 when Richard Markgraf discovered partial remains of a giant theropod in the Bahariya Formation of western Egypt. German paleontologist Ernst Stromer then described these initial findings in 1915 and formally named the new genus and species <em>Spinosaurus aegyptiacus<\/em>, meaning &#8220;Egyptian spine lizard.&#8221; The holotype, or the original specimen used to define the species, included parts of its lower jaw, teeth, various vertebrae (neck, trunk, and sacral), ribs, and <em>gastralia<\/em> (belly ribs). Crucially, it included nine \u201cneural spines\u201d\u2014long extensions of the vertebrae that formed the distinctive sail-like structure on its back, with one reaching an impressive 1.65 meters (5.4 ft) in length. Stromer also designated other fragmentary remains, including vertebrae and hindlimb bones, as &#8220;Spinosaurus B&#8221; in 1934, considering them distinct enough to belong to another species, which later appeared to pertain to <em>Carcharodontosaurus<\/em> or <em>Sigilmassasaurus<\/em>.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This 2020 reconstruction shows Spinosaurus with its newly described, powerful paddle-like tail. This discovery revolutionized our understanding, suggesting the dinosaur was highly adapted for swimming and hunting in water. (&quot;Spinosaurus aegyptiacus&quot; by\u00a0Gustavo Monroy-Becerril\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/e\/e0\/Spinosaurus_aegyptiacus.png\/2560px-Spinosaurus_aegyptiacus.png\" ><figcaption class=\"wp-element-caption\">This 2020 reconstruction shows <em>Spinosaurus<\/em> with its newly described, powerful paddle-like tail. This discovery revolutionized our understanding, suggesting the dinosaur was highly adapted for swimming and hunting in water. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=89667084\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus aegyptiacus<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:GusTrex\" target=\"_blank\" rel=\"noreferrer noopener\">Gustavo Monroy-Becerril<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<p class=\"\">Tragically, this invaluable original specimen was destroyed during a British bombing raid on Munich in April 1944, amidst World War II, which severely damaged the building housing the <a href=\"https:\/\/bspg.snsb.de\/palaeontologisches-museum-muenchen\/\" target=\"_blank\" rel=\"noreferrer noopener\">Pal\u00e4ontologisches Museum M\u00fcnchen<\/a>. Fortunately, Stromer&#8217;s detailed drawings and specimen descriptions survived, providing the only concrete evidence of <em>Spinosaurus<\/em> for decades. This loss would significantly complicate future research, forcing paleontologists to piece together its anatomy from fragmentary discoveries. Early on, some even suggested Stromer&#8217;s original specimen might have been a &#8220;<em>chimera<\/em>&#8221; (a mix of bones from different animals), though this idea was later largely rejected.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"Paleontologists at work in the Kem Kem Beds of North Africa, a region often called the &quot;Dinosaur Mines&quot; due to its incredible wealth of fossils. This harsh desert environment, once a lush river system 100 million years ago, is where many Spinosaurus remains have been unearthed, helping scientists piece together its story. (&quot;At the &#039;Dinosau Mines&#039; - Early Cretaceous Kem Kem beds&quot; by\u00a0GOC53\u00a0is licensed under\u00a0CC BY 2.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/live.staticflickr.com\/897\/40475288640_5586b4e075_h.jpg\" ><figcaption class=\"wp-element-caption\">Paleontologists at work in the Kem Kem Beds of North Africa, a region often called the &#8220;Dinosaur Mines&#8221; due to its incredible wealth of fossils. This harsh desert environment, once a lush river system 100 million years ago, is where many <em>Spinosaurus<\/em> remains have been unearthed, helping scientists piece together its story. (&#8220;<a href=\"https:\/\/www.flickr.com\/photos\/30659367@N00\/40475288640\" target=\"_blank\" rel=\"noreferrer noopener\">At the &#8216;Dinosau Mines&#8217; &#8211; Early Cretaceous Kem Kem beds<\/a>&#8221; by\u00a0<a href=\"https:\/\/www.flickr.com\/photos\/30659367@N00\" target=\"_blank\" rel=\"noreferrer noopener\">GOC53<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY 2.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h1 id=\"a-dinosaur-in-flux\" class=\"wp-block-heading\">A Dinosaur in Flux<\/h1>\n\n\n\n<p class=\"\">The destruction of the holotype meant that <em>Spinosaurus<\/em> remained a shadowy figure for many years. Fragmentary new material came to light in the early 21<sup>st<\/sup> century, often sparking new controversies.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"Based on the latest fossil findings, this dynamic illustration depicts Spinosaurus as an active aquatic hunter, using its powerful, paddle-like tail to pursue prey like this prehistoric lungfish. New evidence suggests Spinosaurus spent significant time submerged, unlike most other giant dinosaurs. (&quot;Spinosaurus hunting underwater&quot; by\u00a0Denny Navarra\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/d\/da\/Spinosaurus_hunting_underwater.png\/1280px-Spinosaurus_hunting_underwater.png\" ><figcaption class=\"wp-element-caption\">Based on the latest fossil findings, this dynamic illustration depicts <em>Spinosaurus<\/em> as an active aquatic hunter, using its powerful, paddle-like tail to pursue prey like this prehistoric lungfish. New evidence suggests <em>Spinosaurus<\/em> spent significant time submerged, unlike most other giant dinosaurs. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=90123295\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus hunting underwater<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?title=User:D-Raptor7&amp;action=edit&amp;redlink=1\" target=\"_blank\" rel=\"noreferrer noopener\">Denny Navarra<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h2 id=\"the-species-debate\" class=\"wp-block-heading\">The Species Debate<\/h2>\n\n\n\n<p class=\"\">One of the earliest debates centered on the existence of a second species. In 1996, Dale Russell described <em>Spinosaurus maroccanus <\/em>from Morocco based on differences in neck vertebrae. However, many researchers quickly considered <em>S. maroccanus<\/em> a <em>nomen dubium <\/em>(a dubious name), meaning its distinctness was uncertain or a <em>junior synonym<\/em> of <em>S. aegyptiacus<\/em>. The variability in individual vertebrae and the absence of the <em>S. aegyptiacus<\/em> holotype for direct comparison contributed to this uncertainty.<\/p>\n\n\n\n<h2 id=\"new-specimens-and-drastic-reconstructions\" class=\"wp-block-heading\">New Specimens and Drastic Reconstructions<\/h2>\n\n\n\n<p class=\"\">New specimens fueled increasingly radical reconstructions. In 2005, a significant snout specimen (MSNM V4047) from the Kem Kem Beds of Morocco was described, which helped paleontologists estimate the <em>Spinosaurus<\/em> skull to be around 1.75 meters (5.7 ft) long. However, more recent estimates suggest a length of 1.6\u20131.68 meters (5.2\u20135.5 ft). This initially led to size estimates suggesting <em>Spinosaurus<\/em> could have been over 15 meters (49 ft) long, making it a contender for the largest known terrestrial carnivore, surpassing even <em>Tyrannosaurus<\/em> and <em>Giganotosaurus<\/em>.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This diagram compares the estimated sizes of several well-known dinosaurs, including the immense Supersaurus and the armored Stegosaurus, to an average human (far left). Highlighted in green, Spinosaurus is one of the most enormous predatory dinosaurs, emphasizing its imposing scale within its ancient ecosystem. (&quot;Longest dinosaur by clade&quot; by\u00a0KoprX\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/e\/e6\/Longest_dinosaur_by_clade.svg\/1280px-Longest_dinosaur_by_clade.svg.png\" ><figcaption class=\"wp-element-caption\">This diagram compares the estimated sizes of several well-known dinosaurs, including the immense <em>Supersaurus<\/em> and the armored <em>Stegosaurus<\/em>, to an average human (far left). Highlighted in green, <em>Spinosaurus<\/em> is one of the most enormous predatory dinosaurs, emphasizing its imposing scale within its ancient ecosystem. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=79141891\" target=\"_blank\" rel=\"noreferrer noopener\">Longest dinosaur by clade<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:KoprX\" target=\"_blank\" rel=\"noreferrer noopener\">KoprX<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<p class=\"\">A significant turning point came in 2014 with the description of FSAC-KK 11888, a partial subadult skeleton recovered from the Kem Kem Beds, a highly fossiliferous Early Cretaceous (around 100 million years old) riverine ecosystem in eastern Morocco. This specimen, controversially designated as a \u201c<em>neotype<\/em>\u201d (a new type specimen when the original is lost, though some researchers later rejected this designation), revealed unexpectedly short hind limbs. This finding led <a href=\"https:\/\/www.port.ac.uk\/about-us\/structure-and-governance\/our-people\/our-staff\/nizar-ibrahim\" target=\"_blank\" rel=\"noreferrer noopener\">Nizar Ibrahim<\/a> and his colleagues in 2014 to propose that <em>Spinosaurus<\/em> was poorly adapted for bipedal (two-legged) terrestrial locomotion and might have been an <em>obligate quadruped<\/em> (walking on four legs) on land, a stark contrast to how theropods are typically envisioned. This idea was met with immediate skepticism and criticism from other paleontologists, who questioned the scaling and integrity of the composite specimen.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This impressive cast of Spinosaurus (based on fossil material known as of 2023) is displayed in a unique swimming posture at the Field Museum of Natural History. Its pose reflects 2022 research suggesting Spinosaurus was highly specialized for an aquatic lifestyle, possibly hunting underwater. (&quot;FSAC-KK-11888&quot; by\u00a03blindMies\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/f\/f0\/FSAC-KK-11888.jpg\/1280px-FSAC-KK-11888.jpg\" ><figcaption class=\"wp-element-caption\">This impressive cast of <em>Spinosaurus<\/em> (based on fossil material known as of 2023) is displayed in a unique swimming posture at the <a href=\"https:\/\/www.fieldmuseum.org\/\" target=\"_blank\" rel=\"noreferrer noopener\">Field Museum of Natural History<\/a>. Its pose reflects 2022 research suggesting <em>Spinosaurus<\/em> was highly specialized for an aquatic lifestyle, possibly hunting underwater. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=133051681\" target=\"_blank\" rel=\"noreferrer noopener\">FSAC-KK-11888<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?title=User:3blindMies&amp;action=edit&amp;redlink=1\" target=\"_blank\" rel=\"noreferrer noopener\">3blindMies<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This diagram illustrates the impressive range of sizes among different Spinosaurus specimens discovered over time, from smaller individuals to the massive fully grown adults. It also highlights how paleontologists use fragments of fossils to reconstruct the full size of these giant predators. (&quot;Spinosaurus size comparison&quot; by\u00a0KoprX\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/f\/f6\/Spinosaurus_size_comparison.svg\/1280px-Spinosaurus_size_comparison.svg.png\" ><figcaption class=\"wp-element-caption\">This diagram illustrates the impressive range of sizes among different <em>Spinosaurus<\/em> specimens discovered over time, from smaller individuals to the massive fully grown adults. It also highlights how paleontologists use fragments of fossils to reconstruct the full size of these giant predators. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=79142963\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus size comparison<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:KoprX\" target=\"_blank\" rel=\"noreferrer noopener\">KoprX<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h2 id=\"the-paddle-like-tail\" class=\"wp-block-heading\">The Paddle-Like Tail<\/h2>\n\n\n\n<p class=\"\">Further revolutionary insights emerged in 2020 with the discovery and analysis of <em>Spinosaurus<\/em>&#8216;s tail vertebrae by Ibrahim and colleagues. They revealed that its long, narrow tail was deepened by tall neural spines and elongated chevron bones, forming a flexible, paddle-like structure comparable to the tails of newts and crocodilians. Experiments showed this tail could generate significantly more thrust in water than the tails of land-dwelling theropods, suggesting <em>Spinosaurus<\/em> could swim effectively, akin to modern crocodilians. This led to the hypothesis that <em>Spinosaurus<\/em> had a lifestyle comparable to alligators, spending long periods in the water while hunting.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This is an artist&#039;s interpretation of S. aegyptiacus, showcasing its distinct, paddle-shaped tail. This feature, revealed by 2020 fossil discoveries, is key evidence that this giant dinosaur was uniquely adapted for a semi-aquatic lifestyle, much like a modern crocodile or alligator. (&quot;Life reconstruction of Spinosaurus aegyptiacus&quot; by\u00a0Connor Ashbridge\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/lh7-rt.googleusercontent.com\/docsz\/AD_4nXckCFyF3cM49ewZI7RXOY6i3TCB9qSIkAQVbNL0DLmAvF5eetB5-K3YXRe0TNrXOjdq18Ik4NTwoa67dBjpQm9fZWawL7Z2I1QXhqsfQ9N5HXuYtRgBcISK9nFgqvRwR411J4CHQg?key=Qathttps:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/9\/9b\/Life_reconstruction_of_Spinosaurus_aegyptiacus.png\/1280px-Life_reconstruction_of_Spinosaurus_aegyptiacus.pngM1rYtyQ7-4o0JL9qyTQ\" ><figcaption class=\"wp-element-caption\">This is an artist&#8217;s interpretation of <em>S. aegyptiacus<\/em>, showcasing its distinct, paddle-shaped tail. This feature, revealed by 2020 fossil discoveries, is key evidence that this giant dinosaur was uniquely adapted for a semi-aquatic lifestyle, much like a modern crocodile or alligator. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=130052152\" target=\"_blank\" rel=\"noreferrer noopener\">Life reconstruction of Spinosaurus aegyptiacus<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?title=User:Ddinodan&amp;action=edit&amp;redlink=1\" target=\"_blank\" rel=\"noreferrer noopener\">Connor Ashbridge<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h2 id=\"bone-density-insights\" class=\"wp-block-heading\">Bone Density Insights<\/h2>\n\n\n\n<p class=\"\">In 2022, research by <a href=\"https:\/\/www.researchgate.net\/profile\/Matteo-Fabbri-8\" target=\"_blank\" rel=\"noreferrer noopener\">Matteo Fabbri<\/a> and colleagues provided strong support for aquatic adaptation by analyzing bone density. They found that <em>Spinosaurus<\/em> had osteosclerosis (high bone density), similar to aquatic animals like penguins and manatees, which would have allowed it to control buoyancy for diving and pursuing prey underwater. This study involved comparing bone cross-sections from 250 species of extinct and living animals, establishing a strong correlation between dense bones and the ability to submerge foraging. Interestingly, they found that a close relative, <em>Suchomimus<\/em>, who lived by water and ate fish, had hollower bones, suggesting it was more of a wader than a submerged swimmer.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This atmospheric illustration by Silvia Pasqualetto vividly portrays Spinosaurus submerged in its watery habitat. This depiction aligns with 2022 research, which found that Spinosaurus had unusually dense bones, much like modern diving animals, helping it control its buoyancy for underwater hunting. (&quot;Spinosaurus by Silvia Pasqualetto @&quot; by\u00a0RobinGoodfellow_(m)\u00a0is marked with\u00a0Public Domain Mark 1.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/live.staticflickr.com\/1916\/44061005515_8a80c11c43_o.jpg\" ><figcaption class=\"wp-element-caption\">This atmospheric illustration by <a href=\"https:\/\/www.instagram.com\/silviapasqualetto\/\" target=\"_blank\" rel=\"noreferrer noopener\">Silvia Pasqualetto<\/a> vividly portrays <em>Spinosaurus<\/em> submerged in its watery habitat. This depiction aligns with 2022 research, which found <em>that Spinosaurus<\/em> had unusually dense bones, much like modern diving animals, helping it control its buoyancy for underwater hunting. (&#8220;<a href=\"https:\/\/www.flickr.com\/photos\/130140542@N03\/44061005515\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus by Silvia Pasqualetto @<\/a>&#8221; by\u00a0<a href=\"https:\/\/www.flickr.com\/photos\/130140542@N03\" target=\"_blank\" rel=\"noreferrer noopener\">RobinGoodfellow_(m)<\/a>\u00a0is marked with\u00a0<a href=\"https:\/\/creativecommons.org\/publicdomain\/mark\/1.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">Public Domain Mark 1.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h2 id=\"diet-and-sensory-adaptations\" class=\"wp-block-heading\">Diet and Sensory Adaptations<\/h2>\n\n\n\n<p class=\"\">From its crocodilian-like skull with conical, unserrated teeth and raised nostrils, paleontologists have long suspected it was a piscivore (fish-eater). Direct evidence came from its relative, <em>Baryonyx<\/em>, whose stomach contained fish scales and bones. Scientists hypothesized <em>that Spinosaurus<\/em> used its snout&#8217;s pressure receptors to detect prey underwater, much like modern crocodiles. Bite force estimates suggest <em>Spinosaurus<\/em> had relatively weak bite forces compared to other theropods but were adapted for fast-snapping jaws to kill prey, a trait common in semi-aquatic feeders. Beyond fish, a 2024 paper suggests <em>Spinosaurus<\/em> and other spinosaurines also preyed upon small to medium-sized terrestrial vertebrates and even pterosaurs. Like a thresher shark&#8217;s, its long tail may also have been used to slap the water and stun fish.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This detailed illustration brings to life Spinosaurus in its ancient riverine habitat, surrounded by its presumed prey, such as the large sawfish Onchopristis (bottom), lungfish like Ceratodus and Bawitius, and the massive Mawsonia. Its long snout and conical teeth were perfectly adapted for catching fish. (&quot;Underwater Spinosaurus ecology&quot; by ABelov2014 is licensed under\u00a0CC BY 3.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/9\/94\/Underwater_Spinosaurus_ecology.jpg\/1280px-Underwater_Spinosaurus_ecology.jpg\" ><figcaption class=\"wp-element-caption\">This detailed illustration brings to life <em>Spinosaurus<\/em> in its ancient riverine habitat, surrounded by its presumed prey, such as the large sawfish <em>Onchopristis<\/em> (bottom), lungfish like <em>Ceratodus<\/em> and <em>Bawitius<\/em>, and the massive <em>Mawsonia<\/em>. Its long snout and conical teeth were perfectly adapted for catching fish. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=73798999\" target=\"_blank\" rel=\"noreferrer noopener\">Underwater Spinosaurus ecology<\/a>&#8221; by ABelov2014 is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by\/3.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY 3.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<p class=\"\">Recent research in 2023 on the brains and inner ears of British spinosaurids, <em>Baryonyx<\/em> and <em>Ceratosuchops<\/em>, showed that their brains and sensory adaptations were surprisingly &#8220;nonspecialized&#8221; despite their unique ecology. Their olfactory bulbs (for smell) were not particularly developed, and their ears were attuned to low-frequency sounds. This suggests that the theropod ancestors of spinosaurs might have already possessed brains and sensory adaptations suited for part-time fish catching, meaning <em>Spinosaurus<\/em> primarily needed to evolve its unusual snout and teeth for its specialized diet. These insights were gained through advanced CT-based imaging of fossils.<\/p>\n\n\n\n<h2 id=\"spinosaurid-origins\" class=\"wp-block-heading\">Spinosaurid Origins<\/h2>\n\n\n\n<p class=\"\">The discovery of <em>Protathlitis cinctorrensis<\/em>, a new spinosaurid species from Spain dating back to the Early Cretaceous (127-126 million years ago), has shed light on the broader evolutionary history of spinosaurids. This finding supports the hypothesis that spinosaurids may have originated in Europe (specifically Laurasia, a large landmass in the northern hemisphere) and then migrated to Africa and Asia, where they diversified. In Europe, baryonychines like <em>Protathlitis<\/em> were dominant, while in Africa, spinosaurines like <em>Spinosaurus<\/em> became most abundant.<\/p>\n\n\n\n<h1 id=\"a-bunch-of-lingering-mysteries\" class=\"wp-block-heading\">A Bunch of Lingering Mysteries<\/h1>\n\n\n\n<p class=\"\">The journey of <em>Spinosaurus<\/em> from a vague, sail-backed theropod to a highly specialized, semi-aquatic predator has been a rollercoaster of discovery and reinterpretation. However, as new evidence emerges, so do new questions and controversies.<\/p>\n\n\n\n<h2 id=\"the-great-aquatic-debate\" class=\"wp-block-heading\">The Great Aquatic Debate<\/h2>\n\n\n\n<p class=\"\">The most heated debate continues to be about <em>Spinosaurus<\/em>&#8216;s primary aquatic lifestyle. While the paddle-like tail and bone density strongly suggest active swimming and submersion, these findings have faced significant challenges.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This detailed chart places S. aegyptiacus (center) within its ancient North African river ecosystem, surrounded by various contemporary aquatic life forms like giant sawfish (Onchopristis) and large lungfish. It highlights Spinosaurus&#039;s debated role as a crucial link for nutrient flow between the land and water environments. (&quot;Spinosaurus with contemporaneous taxa&quot; by Artwork by Joschua Kn\u00fcppe. Article by Jamale Ijouiher. is licensed under\u00a0CC BY 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/7\/75\/Spinosaurus_with_contemporaneous_taxa.jpg\" ><figcaption class=\"wp-element-caption\">This detailed chart places <em>S. aegyptiacus<\/em> (center) within its ancient North African river ecosystem, surrounded by various contemporary aquatic life forms like giant sawfish (<em>Onchopristis<\/em>) and large lungfish. It highlights <em>Spinosaurus<\/em>&#8216;s debated role as a crucial link for nutrient flow between the land and water environments. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=51885662\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus with contemporaneous taxa<\/a>&#8221; by Artwork by Joschua Kn\u00fcppe. Article by Jamale Ijouiher. is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"\">In 2018, <a href=\"https:\/\/tyrrellmuseum.com\/research\/scientists\/don_henderson\" target=\"_blank\" rel=\"noopener\">Donald Henderson<\/a> argued that <em>Spinosaurus<\/em>&#8216;s lung placement and buoyancy would have made it unable to sink or dive, suggesting it needed to paddle its hind legs to stay upright in water constantly. He theorized it likely spent most of its time on land or in shallow water.<\/li>\n\n\n\n<li class=\"\"><a href=\"https:\/\/www.davehone.co.uk\/\" target=\"_blank\" rel=\"noopener\">David Hone<\/a> and <a href=\"https:\/\/www.geol.umd.edu\/~tholtz\/\" target=\"_blank\" rel=\"noopener\">Thomas Holtz<\/a> further argued in 2021 that <em>Spinosaurus<\/em>&#8216;s anatomy, including its ventrally positioned nostrils (requiring the whole head to be lifted to breathe), seemingly rigid trunk, and scarcely muscled tail, was poorly suited for active aquatic pursuit, suggesting a more shoreline generalist lifestyle.<\/li>\n\n\n\n<li class=\"\">Adding to the complexity, a 2022 study by <a href=\"https:\/\/paulsereno.uchicago.edu\/\" target=\"_blank\" rel=\"noopener\">Paul Sereno<\/a> and his colleagues, creating digital skeletons and flesh models, found that <em>Spinosaurus<\/em> and <em>Suchomimus<\/em> would have been unstable when swimming at the surface and too buoyant to dive and fully submerge. They also suggested that <em>Spinosaurus<\/em> was wholly bipedal on land and a slow-moving surface swimmer, proposing its large tail fin was more for display than primary swimming.<\/li>\n\n\n\n<li class=\"\">Most recently, in 2024, <a href=\"https:\/\/nathanmyhrvold.com\/\" target=\"_blank\" rel=\"noopener\">Nathan Myhrvold<\/a> and colleagues re-evaluated the bone density study, highlighting significant statistical issues that &#8220;undermine the conclusions.&#8221; They contended that <em>Spinosaurus<\/em> was not a diving pursuit predator, suggesting it hunted more like herons, wading and plucking prey from the water. They explained that dense bone in <em>Spinosaurus<\/em> could be due to needing extra bone strength to support its weight on its relatively short hind limbs, rather than indicating buoyancy control for diving. Another 2024 paper analyzing <em>Spinosaurus<\/em>&#8216;s skull morphology also concluded that its hunting method would likely be most similar to wading birds.<\/li>\n<\/ul>\n\n\n\n<h2 id=\"locomotion-on-land\" class=\"wp-block-heading\">Locomotion on Land<\/h2>\n\n\n\n<p class=\"\">The debate over <em>Spinosaurus<\/em>&#8216;s terrestrial locomotion continues to evolve. While the 2014 partial skeleton (FSAC-KK 11888) led to the idea of an obligate quadruped, this has mainly been walked back.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"\">Henderson&#8217;s 2018 analysis suggested <em>that Spinosaurus<\/em> was competent at bipedal locomotion, with its center of mass allowing it to stand upright.<\/li>\n\n\n\n<li class=\"\">Most recently, in a 2024 article, Sereno and his colleagues, who had earlier supported quadrupedality, rectified their calculations. They now state that <em>Spinosaurus<\/em> fits the criteria of a graviportal biped, meaning a slow-moving, two-legged animal rather than an obligate quadruped. This shows the ongoing dynamic nature of <em>Spinosaurus<\/em> research.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This large-scale model of Spinosaurus at the Museu Blau in Barcelona depicts it in a bipedal (two-legged) stance, reflecting a more recent scientific understanding of its movement on land. While earlier research suggested it might have walked on four legs, current views lean towards it being a slow-moving, two-legged animal. (&quot;Spinosaurus - Museu Blau - 2016 - 01&quot; by\u00a0Jordiferrer\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/f\/f4\/Spinosaurus_-_Museu_Blau_-_2016_-_01.jpg\/1280px-Spinosaurus_-_Museu_Blau_-_2016_-_01.jpg\" ><figcaption class=\"wp-element-caption\">This large-scale model of <em>Spinosaurus<\/em> at the <a href=\"https:\/\/www.barcelona.de\/en\/barcelona-museum-blau.html\" target=\"_blank\" rel=\"noreferrer noopener\">Museu Blau<\/a> in Barcelona depicts it in a bipedal (two-legged) stance, reflecting a more recent scientific understanding of its movement on land. While earlier research suggested it might have walked on four legs, current views lean towards it being a slow-moving, two-legged animal. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=55836587\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus &#8211; Museu Blau &#8211; 2016 &#8211; 01<\/a>&#8221; by\u00a0<a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Jordiferrer\" target=\"_blank\" rel=\"noreferrer noopener\">Jordiferrer<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<h2 id=\"taxonomic-identity-and-geographic-range\" class=\"wp-block-heading\">Taxonomic Identity and Geographic Range<\/h2>\n\n\n\n<p class=\"\">The exact number of <em>Spinosaurus<\/em> species and the relationships among North African spinosaurids remain contentious.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"\">Some scientists continue to consider the genus <em>Sigilmassasaurus<\/em>, another spinosaurid from North Africa, a junior synonym of <em>Spinosaurus<\/em>. However, a 2015 re-description disputed this, considering <em>Sigilmassasaurus<\/em> valid. In 2024, a complete posterior cervical vertebra was assigned to <em>Sigilmassasaurus brevicollis<\/em>, implying it is still considered distinct by some researchers.<\/li>\n\n\n\n<li class=\"\">The Brazilian spinosaurid <em>Oxalaia<\/em> is also a subject of debate. While a 2020 paper proposed it as a potential junior synonym of <em>Spinosaurus aegyptiacus<\/em>, implying a broader geographic distribution and faunal exchange between South America and Africa, later studies in 2021 and 2023 rejected this synonymy, pointing to distinct skull features of <em>Oxalaia<\/em>. The status of <em>Oxalaia<\/em> is further complicated by the 2018 <a href=\"https:\/\/www.museunacional.ufrj.br\/\" target=\"_blank\" rel=\"noopener\">National Museum of Brazil<\/a> fire, though badly damaged remains have been recovered, and a publication is in preparation for 2025.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img  decoding=\"async\"  src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEUAAP+KeNJXAAAAAXRSTlMAQObYZgAAAAlwSFlzAAAOxAAADsQBlSsOGwAAAApJREFUCNdjYAAAAAIAAeIhvDMAAAAASUVORK5CYII=\"  alt=\"This detailed 2020 reconstruction by Mario Lanzas encapsulates our most current understanding of S. aegyptiacus. It showcases its unique sail, long crocodile-like snout, and newly discovered paddle-like tail, illustrating a giant dinosaur that likely thrived in both terrestrial and aquatic environments of ancient North Africa. (&quot;Spinosaurus 2020 reconstruction&quot; by\u00a0User:Mariolanzas\u00a0is licensed under\u00a0CC BY-SA 4.0.)\"  class=\" pk-lazyload\"  data-pk-sizes=\"auto\"  data-pk-src=\"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/7\/70\/Spinosaurus_2020_reconstruction.jpg\" ><figcaption class=\"wp-element-caption\">This detailed 2020 reconstruction by <a href=\"https:\/\/x.com\/mariolanzas5\" target=\"_blank\" rel=\"noreferrer noopener\">Mario Lanzas<\/a> encapsulates our most current understanding of <em>S. aegyptiacus<\/em>. It showcases its unique sail, long crocodile-like snout, and newly discovered paddle-like tail, illustrating a giant dinosaur that likely thrived in both terrestrial and aquatic environments of ancient North Africa. (&#8220;<a href=\"https:\/\/commons.wikimedia.org\/w\/index.php?curid=89602855\" target=\"_blank\" rel=\"noreferrer noopener\">Spinosaurus 2020 reconstruction<\/a>&#8221; by\u00a0<a href=\"https:\/\/www.deviantart.com\/mariolanzas\" target=\"_blank\" rel=\"noreferrer noopener\">User:Mariolanzas<\/a>\u00a0is licensed under\u00a0<a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/?ref=openverse\" target=\"_blank\" rel=\"noreferrer noopener\">CC BY-SA 4.0<\/a>.)<\/figcaption><\/figure>\n\n\n\n<p class=\"\">The ongoing debates highlight the challenging nature of paleontological research, where scientists must piece together the lives of extinct animals from incomplete fossil records. Each new bone, each new analysis, reshapes our understanding of this magnificent creature. As new technologies like CT-based imaging and advanced statistical methods allow for more detailed examination of fossil fragments and biomechanical modeling, the true nature of <em>Spinosaurus<\/em> continues to emerge, cementing its place as one of the most dynamic and debated dinosaurs in the history of science.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 id=\"references\" class=\"wp-block-heading\">References<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li class=\"\">Amiot, R., Buffetaut, E., L\u00e9cuyer, C., Wang, X., Boudad, L., Ding, Z., Fourel, F., Hutt, S., Martineau, F., Medeiros, M. A., Mo, J., Simon, L., Suteethorn, V., Sweetman, S., Tong, H., Zhang, F., &amp; Zhou, Z. (2010). Oxygen isotope evidence for semi-aquatic habits among spinosaurid theropods. <em>Geology<\/em>, <em>38<\/em>(2), 139\u2013142. <a href=\"https:\/\/doi.org\/10.1130\/G30402.1\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1130\/G30402.1<\/a><\/li>\n\n\n\n<li class=\"\">Arden, T. M. S., Klein, C. G., Zouhri, S., &amp; Longrich, N. R. (2019). Aquatic adaptation in the skull of carnivorous dinosaurs (Theropoda: Spinosauridae) and the evolution of aquatic habits in spinosaurids. <em>Cretaceous Research<\/em>, <em>93<\/em>, 275\u2013284. <a href=\"https:\/\/doi.org\/10.1016\/j.cretres.2018.06.013\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1016\/j.cretres.2018.06.013<\/a><\/li>\n\n\n\n<li class=\"\">Buffetaut, E., Martill, D., &amp; Escuilli\u00e9, F. (2004). Pterosaurs as part of a spinosaur diet. <em>Nature<\/em>, <em>430<\/em>(6995), 33\u201333. <a href=\"https:\/\/doi.org\/10.1038\/430033a\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1038\/430033a<\/a><\/li>\n\n\n\n<li class=\"\">Cuff, A. R., &amp; Rayfield, E. J. (2013). Feeding mechanics in spinosaurid theropods and extant crocodilians. <em>PLoS ONE<\/em>, <em>8<\/em>(5), e65295. <a href=\"https:\/\/doi.org\/10.1371\/journal.pone.0065295\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1371\/journal.pone.0065295<\/a><\/li>\n\n\n\n<li class=\"\">D\u2019Amore, D. C., Johnson\u2010Ransom, E., Snively, E., &amp; Hone, D. W. E. (2025). Prey size and ecological separation in spinosaurid theropods based on heterodonty and rostrum shape. <em>The Anatomical Record<\/em>, <em>308<\/em>(5), 1331\u20131348. <a href=\"https:\/\/doi.org\/10.1002\/ar.25563\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.1002\/ar.25563<\/a><\/li>\n\n\n\n<li class=\"\">Evers, S. W., Rauhut, O. W. M., Milner, A. C., McFeeters, B., &amp; Allain, R. (2015). A reappraisal of the morphology and systematic position of the theropod dinosaur <em>Sigilmassasaurus<\/em> from the \u201cmiddle\u201d Cretaceous of Morocco. <em>PeerJ<\/em>, <em>3<\/em>, e1323. <a href=\"https:\/\/doi.org\/10.7717\/peerj.1323\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.7717\/peerj.1323<\/a><\/li>\n\n\n\n<li class=\"\">Fabbri, M., Naval\u00f3n, G., Benson, R. B. J., Pol, D., O\u2019Connor, J., Bhullar, B.-A. S., Erickson, G. M., Norell, M. A., Orkney, A., Lamanna, M. 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A buoyancy, balance and stability challenge to the hypothesis of a semi-aquatic <em>Spinosaurus<\/em> Stromer, 1915 (Dinosauria: Theropoda). <em>PeerJ<\/em>, <em>6<\/em>, e5409. <a href=\"https:\/\/doi.org\/10.7717\/peerj.5409\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.7717\/peerj.5409<\/a><\/li>\n\n\n\n<li class=\"\">Hone, D., &amp; Holtz, T. (2021). Evaluating the ecology of Spinosaurus: Shoreline generalist or aquatic pursuit specialist? <em>Palaeontologia Electronica<\/em>. <a href=\"https:\/\/doi.org\/10.26879\/1110\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/doi.org\/10.26879\/1110<\/a><\/li>\n\n\n\n<li class=\"\">Ibrahim, N., Sereno, P. C., Varricchio, D. J., Martill, D. M., Dutheil, D. B., Unwin, D. M., Baidder, L., Larsson, H. C. E., Zouhri, S., &amp; Kaoukaya, A. (2020). 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University of California Press.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"Once a mystery fossil lost to war, Spinosaurus has transformed into one of paleontology\u2019s most debated dinosaurs\u2014reimagined as a semi-aquatic predator, yet still stirring controversy over how it truly lived.\n","protected":false},"author":2,"featured_media":14799,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","fifu_image_url":"https:\/\/live.staticflickr.com\/3518\/4078770483_361e6a3b39_o.jpg","fifu_image_alt":"","footnotes":""},"categories":[18,11],"tags":[11679,11668,11664,11672,11670,11678,11667,11687,11675,11680,11691,11692,11673,11665,11684,11693,11689,11669,11685,11671,11683,11666,11686,11690,11682,11677,11676,11681,11674,11688],"class_list":{"0":"post-14788","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-history","8":"category-nature","9":"tag-aquatic-adaptations-in-theropods","10":"tag-dinosaur-bone-density-studies","11":"tag-late-cretaceous-north-africa-dinosaurs","12":"tag-oxalaia-dinosaur-debate","13":"tag-protathlitis-cinctorrensis-origin","14":"tag-sigilmassasaurus-vs-spinosaurus","15":"tag-spinosaurid-evolutionary-history","16":"tag-spinosaurus-and-pterosaurs","17":"tag-spinosaurus-aquatic-dinosaur","18":"tag-spinosaurus-bone-density","19":"tag-spinosaurus-ct-scan-studies","20":"tag-spinosaurus-diet-fish","21":"tag-spinosaurus-display-structures","22":"tag-spinosaurus-evolution","23":"tag-spinosaurus-fossil-history","24":"tag-spinosaurus-graviportal-biped","25":"tag-spinosaurus-hunting-strategy","26":"tag-spinosaurus-kem-kem-fossils","27":"tag-spinosaurus-locomotion-debate","28":"tag-spinosaurus-neotype-specimen","29":"tag-spinosaurus-paddle-tail","30":"tag-spinosaurus-paleontology-controversies","31":"tag-spinosaurus-quadrupedal-vs-bipedal","32":"tag-spinosaurus-recent-discoveries-2025","33":"tag-spinosaurus-sail-function","34":"tag-spinosaurus-skull-morphology","35":"tag-spinosaurus-swimming-ability","36":"tag-spinosaurus-tail-biomechanics","37":"tag-spinosaurus-tail-propulsion","38":"tag-spinosaurus-vs-suchomimus","39":"cs-entry","40":"cs-video-wrap"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/14788","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/comments?post=14788"}],"version-history":[{"count":2,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/14788\/revisions"}],"predecessor-version":[{"id":14800,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/posts\/14788\/revisions\/14800"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media\/14799"}],"wp:attachment":[{"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/media?parent=14788"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/categories?post=14788"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/modernsciences.org\/staging\/4414\/wp-json\/wp\/v2\/tags?post=14788"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}