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Express Tribune
24-04-2025
- Science
- Express Tribune
Saltwater power turned ancient terror crocodile into a dinosaur-eating giant
Listen to article A colossal, extinct reptile that preyed on dinosaurs had a broad, alligator-like snout—but what truly set it apart was a feature modern alligators lack: the ability to tolerate salt water. Deinosuchus was among the largest crocodilian species ever recorded, stretching nearly the length of a bus and armed with banana-sized teeth. Between 82 and 75 million years ago, this apex predator roamed the rivers and estuaries of ancient North America. Its skull was both wide and elongated, capped with a distinctive bony bulge unseen in other crocodilians. Fossilised bones from the Cretaceous period bearing toothmarks suggest Deinosuchus fed on or scavenged dinosaurs. Though its name means 'terror crocodile,' Deinosuchus was long considered more closely related to alligators and was often nicknamed the 'greater alligator.' Previous research grouped it with ancient and modern alligator species. But fresh fossil evidence, combined with genetic data from living crocodilians proved that deinosuchus belong to the crocodilian family tree. Scientists now say Deinosuchus was not an alligatoroid at all. Unlike its freshwater cousins, it retained the salt glands found in early crocodilians—organs that help regulate salt levels by excreting excess sodium chloride. These are still present in modern crocodiles but absent in today's alligators. This salt tolerance likely gave Deinosuchus a powerful edge during the Late Cretaceous, allowing it to move freely through the Western Interior Seaway—a vast inland sea that split North America during a period of high global sea levels. The predator's range may have extended across both sides of the ancient seaway, including coastal regions along the Atlantic. The newly proposed crocodilian family tree provides deeper understanding of how some species adjusted to environmental changes while others vanished. Thanks to its salt glands, Deinosuchus could colonise ecosystems that its alligator-like relatives could not. With access to coastal marshes filled with large prey, it became one of the most dominant predators of its time—an enormous reptile capable of feeding on nearly anything that crossed its path. 'When Deinosuchus was around, nothing was safe in these wetlands,' said Dr. Márton Rabi, the study's senior author and a lecturer at the University of Tübingen's Institute of Geosciences. 'This was an absolutely monstrous animal—easily eight metres long or more.' To build a clearer picture of crocodilian evolution, researchers incorporated fossil data from previously unsampled extinct species—key 'missing links' that helped clarify long-misunderstood relationships. These additions allowed the team to track when certain traits, such as saltwater tolerance, first emerged within the group. 'Our findings show that salt tolerance is an ancient trait in crocodilians, one that was later lost in alligatoroids,' said study co-author Dr Márton Rabi. This adaptation would have been especially useful as shifting climates altered landscapes, added Dr Evon Hekkala, a biological sciences professor at Fordham University, who was not involved in the research. 'This ecological advantage likely gave some crocodile lineages a better shot at survival during periods of major environmental change, such as rising sea levels,' Hekkala said. The team also reconstructed the crocodilian family tree using genetic data from living species. Their analysis showed that early alligators were considerably smaller than other crocodilians of the time. The evolution of the larger body sizes seen in today's alligators only began around 34 million years ago, likely as a result of climate cooling and the extinction of their competitors. At the time Deinosuchus lived, however, it stood out as a giant among much smaller alligatoroid relatives. This, combined with new insights into early dwarfism in the group, supports the conclusion that Deinosuchus branched off from the family tree before alligatoroids began to evolve. 'Giant crocs are more like the norm — of any time,' Rabi said.
CNN
23-04-2025
- Science
- CNN
An ancient ‘terror crocodile' became a dinosaur-eating giant. Scientists say they now know why
(CNN) — A massive, extinct reptile that once snacked on dinosaurs had a broad snout like an alligator's, but it owed its success to a trait that modern alligators lack: tolerance for salt water. Deinosuchus was one of the largest crocodilians that ever lived, with a body nearly as long as a bus and teeth the size of bananas. From about 82 million to 75 million years ago, the top predator swam in rivers and estuaries of North America. The skull was wide and long, tipped with a bulbous lump that was unlike any skull structure seen in other crocodilians. Toothmarks on Cretaceous bones hint that Deinosuchus hunted or scavenged dinosaurs. Despite its scientific name, which translates as 'terror crocodile,' Deinosuchus has commonly been called a 'greater alligator,' and prior assessments of its evolutionary relationships grouped it with alligators and their ancient relatives. However, a new analysis of fossils, along with DNA from living crocodilians such as alligators and crocodiles, suggests Deinosuchus belongs on a different part of the crocodilian family tree. Unlike alligatoroids, Deinosuchus retained the salt glands of ancestral crocodilians, enabling it to tolerate salt water, scientists reported Wednesday in the journal Communications Biology. Modern crocodiles have these glands, which collect and release excess sodium chloride. Salt tolerance would have helped Deinosuchus navigate the Western Interior Seaway that once divided North America, during a greenhouse phase marked by global sea level rise. Deinosuchus could then have spread across the continent to inhabit coastal marshes on both sides of the ancient inland sea, and along North America's Atlantic coast. The new study's revised family tree for crocodilians offers fresh insights into climate resilience in the group, and hints at how some species adapted to environmental cooling while others went extinct. With salt glands allowing Deinosuchus to travel where its alligatoroid cousins couldn't, the terror crocodile settled in habitats teeming with large prey. Deinosuchus evolved to become an enormous and widespread predator that dominated marshy ecosystems, where it fed on pretty much whatever it wanted. 'No one was safe in these wetlands when Deinosuchus was around,' said senior study author Dr. Márton Rabi, a lecturer in the Institute of Geosciences at the University of Tübingen in Germany. 'We are talking about an absolutely monstrous animal,' Rabi told CNN. 'Definitely around 8 meters (26 feet) or more total body length.' Since the mid-19th century, fossils of Deinosuchus have been found on both sides of the ancient seaway and belong to at least two species. The largest of these, Deinosuchus riograndensis, lived on the western side, along the east coast of an island called Laramidia. Bordered on the west by the Pacific Ocean, Laramidia made up less than one-third of the landmass of North America. The continent's other island portion was known as Appalachia. While Deinosuchus had long been classified as an alligator relative, its distribution on both sides of this vast seaway was an unsolved puzzle. If it was an alligatoroid — a group that today lives only in freshwater — how could Deinosuchus cross a sea spanning more than 620 miles (1,000 kilometers)? One hypothesis suggested that early alligators were saltwater tolerant and then later lost the trait. But that interpretation didn't have much evidence to back it up; it hinged solely on Deinosuchus being included in the alligatoroid group, Rabi explained. Another possible explanation was that Deinosuchus dispersed across North America before the Western Interior Seaway formed and divided western and eastern populations. However, the fossil record doesn't back that up. The seaway appeared about 100 million years ago, making it approximately 20 million years older than the earliest known Deinosuchus fossils. 'The picture wasn't very coherent,' Rabi said. For the new analysis, the researchers incorporated data from extinct crocodilians that were not sampled for the group's earlier family trees. These 'missing links' helped the team connect species that were not previously recognized to be related and reassemble the order in which certain traits emerged in the group. 'Our analysis found that saltwater tolerance is a fairly ancient trait of many crocodilians, and was secondarily lost in the alligatoroids,' Rabi said. Having even a moderate tolerance for salt would have greatly benefited ancient crocodile relatives as climate shifts reshaped their habitats, said Dr. Evon Hekkala, a professor and chair of the department of biological sciences at Fordham University in New York City. 'This ecological trait would have allowed lineages of crocodiles in the past to be more opportunistic in times when drastic environmental changes, such as sea level rise, were causing extinctions in less tolerant species,' said Hekkala, who was not involved in the study. The researchers also constructed a new crocodilian family tree using molecular data from modern crocodilians to clarify features shared by all alligatoroids. The earliest alligators were far smaller than other crocodilians that lived at the same time, the team found. Alligators began to evolve the larger body sizes seen today about 34 million years ago, after the climate cooled and their competition went extinct. But when alligatoroids first appeared, Deinosuchus would have been an outlier due to its massive bulk, according to the new study. Dwarfism in early alligatoroids was another clue that giant Deinosuchus was no 'greater alligator,' and it likely diverged into a different branch of the family tree before alligatoroids evolved, Rabi said. The study's approach — combining a new molecular tree with morphology, or analysis of body and skull shapes in crocodilians — paints a clearer picture of how Deinosuchus evolved, Hekkala said. Shifting Deinosuchus away from alligatoroids 'fits much better with our current understanding of ecological flexibility among the extinct and living crocodiles,' she added. 'This new paper really reaches into both the evolutionary and ecological role of this amazing animal.' While Deinosuchus was one of the largest crocodilians, it wasn't the only giant. Massive crocodilians evolved independently in aquatic environments more than a dozen times over the past 120 million years during all types of global climatic phases — including ice ages, according to the study. Even in living species, reports of individuals measuring 23 feet (7 meters) or more persisted until the 19th century, suggesting enormous Deinosuchus was the rule rather than the exception. 'Giant crocs are more like the norm — of any time,' Rabi said.
CNN
23-04-2025
- Science
- CNN
An ancient ‘terror crocodile' became a dinosaur-eating giant. Scientists say they now know why
(CNN) — A massive, extinct reptile that once snacked on dinosaurs had a broad snout like an alligator's, but it owed its success to a trait that modern alligators lack: tolerance for salt water. Deinosuchus was one of the largest crocodilians that ever lived, with a body nearly as long as a bus and teeth the size of bananas. From about 82 million to 75 million years ago, the top predator swam in rivers and estuaries of North America. The skull was wide and long, tipped with a bulbous lump that was unlike any skull structure seen in other crocodilians. Toothmarks on Cretaceous bones hint that Deinosuchus hunted or scavenged dinosaurs. Despite its scientific name, which translates as 'terror crocodile,' Deinosuchus has commonly been called a 'greater alligator,' and prior assessments of its evolutionary relationships grouped it with alligators and their ancient relatives. However, a new analysis of fossils, along with DNA from living crocodilians such as alligators and crocodiles, suggests Deinosuchus belongs on a different part of the crocodilian family tree. Unlike alligatoroids, Deinosuchus retained the salt glands of ancestral crocodilians, enabling it to tolerate salt water, scientists reported Wednesday in the journal Communications Biology. Modern crocodiles have these glands, which collect and release excess sodium chloride. Salt tolerance would have helped Deinosuchus navigate the Western Interior Seaway that once divided North America, during a greenhouse phase marked by global sea level rise. Deinosuchus could then have spread across the continent to inhabit coastal marshes on both sides of the ancient inland sea, and along North America's Atlantic coast. The new study's revised family tree for crocodilians offers fresh insights into climate resilience in the group, and hints at how some species adapted to environmental cooling while others went extinct. With salt glands allowing Deinosuchus to travel where its alligatoroid cousins couldn't, the terror crocodile settled in habitats teeming with large prey. Deinosuchus evolved to become an enormous and widespread predator that dominated marshy ecosystems, where it fed on pretty much whatever it wanted. 'No one was safe in these wetlands when Deinosuchus was around,' said senior study author Dr. Márton Rabi, a lecturer in the Institute of Geosciences at the University of Tübingen in Germany. 'We are talking about an absolutely monstrous animal,' Rabi told CNN. 'Definitely around 8 meters (26 feet) or more total body length.' Since the mid-19th century, fossils of Deinosuchus have been found on both sides of the ancient seaway and belong to at least two species. The largest of these, Deinosuchus riograndensis, lived on the western side, along the east coast of an island called Laramidia. Bordered on the west by the Pacific Ocean, Laramidia made up less than one-third of the landmass of North America. The continent's other island portion was known as Appalachia. While Deinosuchus had long been classified as an alligator relative, its distribution on both sides of this vast seaway was an unsolved puzzle. If it was an alligatoroid — a group that today lives only in freshwater — how could Deinosuchus cross a sea spanning more than 620 miles (1,000 kilometers)? One hypothesis suggested that early alligators were saltwater tolerant and then later lost the trait. But that interpretation didn't have much evidence to back it up; it hinged solely on Deinosuchus being included in the alligatoroid group, Rabi explained. Another possible explanation was that Deinosuchus dispersed across North America before the Western Interior Seaway formed and divided western and eastern populations. However, the fossil record doesn't back that up. The seaway appeared about 100 million years ago, making it approximately 20 million years older than the earliest known Deinosuchus fossils. 'The picture wasn't very coherent,' Rabi said. For the new analysis, the researchers incorporated data from extinct crocodilians that were not sampled for the group's earlier family trees. These 'missing links' helped the team connect species that were not previously recognized to be related and reassemble the order in which certain traits emerged in the group. 'Our analysis found that saltwater tolerance is a fairly ancient trait of many crocodilians, and was secondarily lost in the alligatoroids,' Rabi said. Having even a moderate tolerance for salt would have greatly benefited ancient crocodile relatives as climate shifts reshaped their habitats, said Dr. Evon Hekkala, a professor and chair of the department of biological sciences at Fordham University in New York City. 'This ecological trait would have allowed lineages of crocodiles in the past to be more opportunistic in times when drastic environmental changes, such as sea level rise, were causing extinctions in less tolerant species,' said Hekkala, who was not involved in the study. The researchers also constructed a new crocodilian family tree using molecular data from modern crocodilians to clarify features shared by all alligatoroids. The earliest alligators were far smaller than other crocodilians that lived at the same time, the team found. Alligators began to evolve the larger body sizes seen today about 34 million years ago, after the climate cooled and their competition went extinct. But when alligatoroids first appeared, Deinosuchus would have been an outlier due to its massive bulk, according to the new study. Dwarfism in early alligatoroids was another clue that giant Deinosuchus was no 'greater alligator,' and it likely diverged into a different branch of the family tree before alligatoroids evolved, Rabi said. The study's approach — combining a new molecular tree with morphology, or analysis of body and skull shapes in crocodilians — paints a clearer picture of how Deinosuchus evolved, Hekkala said. Shifting Deinosuchus away from alligatoroids 'fits much better with our current understanding of ecological flexibility among the extinct and living crocodiles,' she added. 'This new paper really reaches into both the evolutionary and ecological role of this amazing animal.' While Deinosuchus was one of the largest crocodilians, it wasn't the only giant. Massive crocodilians evolved independently in aquatic environments more than a dozen times over the past 120 million years during all types of global climatic phases — including ice ages, according to the study. Even in living species, reports of individuals measuring 23 feet (7 meters) or more persisted until the 19th century, suggesting enormous Deinosuchus was the rule rather than the exception. 'Giant crocs are more like the norm — of any time,' Rabi said.
Yahoo
23-04-2025
- Science
- Yahoo
Scientists discover how a ‘terror crocodile' became a dinosaur-eating giant
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. (CNN) — A massive, extinct reptile that once snacked on dinosaurs had a broad snout like an alligator's, but it owed its success to a trait that modern alligators lack: tolerance for salt water. Deinosuchus was one of the largest crocodilians that ever lived, with a body nearly as long as a bus and teeth the size of bananas. From about 82 million to 75 million years ago, the top predator swam in rivers and estuaries of North America. The skull was wide and long, tipped with a bulbous lump that was unlike any skull structure seen in other crocodilians. Toothmarks on Cretaceous bones hint that Deinosuchus hunted or scavenged dinosaurs. Despite its scientific name, which translates as 'terror crocodile,' Deinosuchus has commonly been called a 'greater alligator,' and prior assessments of its evolutionary relationships grouped it with alligators and their ancient relatives. However, a new analysis of fossils, along with DNA from living crocodilians such as alligators and crocodiles, suggests Deinosuchus belongs on a different part of the crocodilian family tree. Unlike alligatoroids, Deinosuchus retained the salt glands of ancestral crocodilians, enabling it to tolerate salt water, scientists reported Wednesday in the journal Communications Biology. Modern crocodiles have these glands, which collect and release excess sodium chloride. Salt tolerance would have helped Deinosuchus navigate the Western Interior Seaway that once divided North America, during a greenhouse phase marked by global sea level rise. Deinosuchus could then have spread across the continent to inhabit coastal marshes on both sides of the ancient inland sea, and along North America's Atlantic coast. The new study's revised family tree for crocodilians offers fresh insights into climate resilience in the group, and hints at how some species adapted to environmental cooling while others went extinct. With salt glands allowing Deinosuchus to travel where its alligatoroid cousins couldn't, the terror crocodile settled in habitats teeming with large prey. Deinosuchus evolved to become an enormous and widespread predator that dominated marshy ecosystems, where it fed on pretty much whatever it wanted. 'No one was safe in these wetlands when Deinosuchus was around,' said senior study author Dr. Márton Rabi, a lecturer in the Institute of Geosciences at the University of Tübingen in Germany. 'We are talking about an absolutely monstrous animal,' Rabi told CNN. 'Definitely around 8 meters (26 feet) or more total body length.' Since the mid-19th century, fossils of Deinosuchus have been found on both sides of the ancient seaway and belong to at least two species. The largest of these, Deinosuchus riograndensis, lived on the western side, along the east coast of an island called Laramidia. Bordered on the west by the Pacific Ocean, Laramidia made up less than one-third of the landmass of North America. The continent's other island portion was known as Appalachia. While Deinosuchus had long been classified as an alligator relative, its distribution on both sides of this vast seaway was an unsolved puzzle. If it was an alligatoroid — a group that today lives only in freshwater — how could Deinosuchus cross a sea spanning more than 620 miles (1,000 kilometers)? One hypothesis suggested that early alligators were saltwater tolerant and then later lost the trait. But that interpretation didn't have much evidence to back it up; it hinged solely on Deinosuchus being included in the alligatoroid group, Rabi explained. Another possible explanation was that Deinosuchus dispersed across North America before the Western Interior Seaway formed and divided western and eastern populations. However, the fossil record doesn't back that up. The seaway appeared about 100 million years ago, making it approximately 20 million years older than the earliest known Deinosuchus fossils. 'The picture wasn't very coherent,' Rabi said. For the new analysis, the researchers incorporated data from extinct crocodilians that were not sampled for the group's earlier family trees. These 'missing links' helped the team connect species that were not previously recognized to be related and reassemble the order in which certain traits emerged in the group. 'Our analysis found that saltwater tolerance is a fairly ancient trait of many crocodilians, and was secondarily lost in the alligatoroids,' Rabi said. Having even a moderate tolerance for salt would have greatly benefited ancient crocodile relatives as climate shifts reshaped their habitats, said Dr. Evon Hekkala, a professor and chair of the department of biological sciences at Fordham University in New York City. 'This ecological trait would have allowed lineages of crocodiles in the past to be more opportunistic in times when drastic environmental changes, such as sea level rise, were causing extinctions in less tolerant species,' said Hekkala, who was not involved in the study. The researchers also constructed a new crocodilian family tree using molecular data from modern crocodilians to clarify features shared by all alligatoroids. The earliest alligators were far smaller than other crocodilians that lived at the same time, the team found. Alligators began to evolve the larger body sizes seen today about 34 million years ago, after the climate cooled and their competition went extinct. But when alligatoroids first appeared, Deinosuchus would have been an outlier due to its massive bulk, according to the new study. Dwarfism in early alligatoroids was another clue that giant Deinosuchus was no 'greater alligator,' and it likely diverged into a different branch of the family tree before alligatoroids evolved, Rabi said. The study's approach — combining a new molecular tree with morphology, or analysis of body and skull shapes in crocodilians — paints a clearer picture of how Deinosuchus evolved, Hekkala said. Shifting Deinosuchus away from alligatoroids 'fits much better with our current understanding of ecological flexibility among the extinct and living crocodiles,' she added. 'This new paper really reaches into both the evolutionary and ecological role of this amazing animal.' While Deinosuchus was one of the largest crocodilians, it wasn't the only giant. Massive crocodilians evolved independently in aquatic environments more than a dozen times over the past 120 million years during all types of global climatic phases — including ice ages, according to the study. Even in living species, reports of individuals measuring 23 feet (7 meters) or more persisted until the 19th century, suggesting enormous Deinosuchus was the rule rather than the exception. 'Giant crocs are more like the norm — of any time,' Rabi said. Mindy Weisberger is a science writer and media producer whose work has appeared in Live Science, Scientific American and How It Works magazine.
CNN
23-04-2025
- Science
- CNN
Scientists discover how a ‘terror crocodile' became a dinosaur-eating giant
(CNN) — A massive, extinct reptile that once snacked on dinosaurs had a broad snout like an alligator's, but it owed its success to a trait that modern alligators lack: tolerance for salt water. Deinosuchus was one of the largest crocodilians that ever lived, with a body nearly as long as a bus and teeth the size of bananas. From about 82 million to 75 million years ago, the top predator swam in rivers and estuaries of North America. The skull was wide and long, tipped with a bulbous lump that was unlike any skull structure seen in other crocodilians. Toothmarks on Cretaceous bones hint that Deinosuchus hunted or scavenged dinosaurs. Despite its scientific name, which translates as 'terror crocodile,' Deinosuchus has commonly been called a 'greater alligator,' and prior assessments of its evolutionary relationships grouped it with alligators and their ancient relatives. However, a new analysis of fossils, along with DNA from living crocodilians such as alligators and crocodiles, suggests Deinosuchus belongs on a different part of the crocodilian family tree. Unlike alligatoroids, Deinosuchus retained the salt glands of ancestral crocodilians, enabling it to tolerate salt water, scientists reported Wednesday in the journal Communications Biology. Modern crocodiles have these glands, which collect and release excess sodium chloride. Salt tolerance would have helped Deinosuchus navigate the Western Interior Seaway that once divided North America, during a greenhouse phase marked by global sea level rise. Deinosuchus could then have spread across the continent to inhabit coastal marshes on both sides of the ancient inland sea, and along North America's Atlantic coast. The new study's revised family tree for crocodilians offers fresh insights into climate resilience in the group, and hints at how some species adapted to environmental cooling while others went extinct. With salt glands allowing Deinosuchus to travel where its alligatoroid cousins couldn't, the terror crocodile settled in habitats teeming with large prey. Deinosuchus evolved to become an enormous and widespread predator that dominated marshy ecosystems, where it fed on pretty much whatever it wanted. 'No one was safe in these wetlands when Deinosuchus was around,' said senior study author Dr. Márton Rabi, a lecturer in the Institute of Geosciences at the University of Tübingen in Germany. 'We are talking about an absolutely monstrous animal,' Rabi told CNN. 'Definitely around 8 meters (26 feet) or more total body length.' Since the mid-19th century, fossils of Deinosuchus have been found on both sides of the ancient seaway and belong to at least two species. The largest of these, Deinosuchus riograndensis, lived on the western side, along the east coast of an island called Laramidia. Bordered on the west by the Pacific Ocean, Laramidia made up less than one-third of the landmass of North America. The continent's other island portion was known as Appalachia. While Deinosuchus had long been classified as an alligator relative, its distribution on both sides of this vast seaway was an unsolved puzzle. If it was an alligatoroid — a group that today lives only in freshwater — how could Deinosuchus cross a sea spanning more than 620 miles (1,000 kilometers)? One hypothesis suggested that early alligators were saltwater tolerant and then later lost the trait. But that interpretation didn't have much evidence to back it up; it hinged solely on Deinosuchus being included in the alligatoroid group, Rabi explained. Another possible explanation was that Deinosuchus dispersed across North America before the Western Interior Seaway formed and divided western and eastern populations. However, the fossil record doesn't back that up. The seaway appeared about 100 million years ago, making it approximately 20 million years older than the earliest known Deinosuchus fossils. 'The picture wasn't very coherent,' Rabi said. For the new analysis, the researchers incorporated data from extinct crocodilians that were not sampled for the group's earlier family trees. These 'missing links' helped the team connect species that were not previously recognized to be related and reassemble the order in which certain traits emerged in the group. 'Our analysis found that saltwater tolerance is a fairly ancient trait of many crocodilians, and was secondarily lost in the alligatoroids,' Rabi said. Having even a moderate tolerance for salt would have greatly benefited ancient crocodile relatives as climate shifts reshaped their habitats, said Dr. Evon Hekkala, a professor and chair of the department of biological sciences at Fordham University in New York City. 'This ecological trait would have allowed lineages of crocodiles in the past to be more opportunistic in times when drastic environmental changes, such as sea level rise, were causing extinctions in less tolerant species,' said Hekkala, who was not involved in the study. The researchers also constructed a new crocodilian family tree using molecular data from modern crocodilians to clarify features shared by all alligatoroids. The earliest alligators were far smaller than other crocodilians that lived at the same time, the team found. Alligators began to evolve the larger body sizes seen today about 34 million years ago, after the climate cooled and their competition went extinct. But when alligatoroids first appeared, Deinosuchus would have been an outlier due to its massive bulk, according to the new study. Dwarfism in early alligatoroids was another clue that giant Deinosuchus was no 'greater alligator,' and it likely diverged into a different branch of the family tree before alligatoroids evolved, Rabi said. The study's approach — combining a new molecular tree with morphology, or analysis of body and skull shapes in crocodilians — paints a clearer picture of how Deinosuchus evolved, Hekkala said. Shifting Deinosuchus away from alligatoroids 'fits much better with our current understanding of ecological flexibility among the extinct and living crocodiles,' she added. 'This new paper really reaches into both the evolutionary and ecological role of this amazing animal.' While Deinosuchus was one of the largest crocodilians, it wasn't the only giant. Massive crocodilians evolved independently in aquatic environments more than a dozen times over the past 120 million years during all types of global climatic phases — including ice ages, according to the study. Even in living species, reports of individuals measuring 23 feet (7 meters) or more persisted until the 19th century, suggesting enormous Deinosuchus was the rule rather than the exception. 'Giant crocs are more like the norm — of any time,' Rabi said.
