Sarcosuchus (flesh crocodile), and commonly called "SuperCroc", is an extinct genus of crocodyliform and distant relative of the crocodile that lived 112 million years ago. It dates from the early Cretaceous Period of what is now Africa and is one of the largest giant crocodile-like reptiles that ever lived. It was almost twice as long as the modern saltwater crocodile and weighed approximately 8 to 10 tonnes.
Until recently, all that was known of the genus was a few fossilised teeth and armour scutes, which were discovered in the Sahara Desert by the French paleontologist Albert-Félix de Lapparent, in the 1940s or 1950s. He called it the "Aoulef crocodile". However, in 1997 and 2000, American paleontologist Paul Sereno discovered half a dozen new specimens, hncluding one with about half the skeleton intact and most of the spine. All of the other giant crocodiles are known only from a few partial skulls, so which is actually the biggest is an open question.
Until recently, all that was known of the genus was a few fossilised teeth and armour scutes, which were discovered in the Sahara Desert by the French paleontologist Albert-Félix de Lapparent, in the 1940s or 1950s. He called it the "Aoulef crocodile". However, in 1997 and 2000, American paleontologist Paul Sereno discovered half a dozen new specimens, hncluding one with about half the skeleton intact and most of the spine. All of the other giant crocodiles are known only from a few partial skulls, so which is actually the biggest is an open question.
When fully mature, Sarcosuchus is believed to have been as long as a city bus (11.2–12.2 metres or 37–40 ft) and weighed up to 8 tonnes (8.75 tons).[1] The largest living crocodilian, the saltwater crocodile, is less than two-thirds of that length (6.3 meters or 20.6 ft is the longest confirmed individual) and a small fraction of the weight (1,200 kg, or 1.3 tons).
The very largest Sarcosuchus is believed to have been the oldest. Osteoderm growth rings taken from an 80% grown individual (based on comparison to largest individual found) suggest that Sarcosuchus kept growing throughout its entire 50–60 year average life span. Modern crocodiles grow at a rapid rate, reaching their adult size in about a decade, then growing more slowly afterward.
Its skull alone was as big as a human adult (1.78 m, or 5 ft 10 inches). The upper jaw overlapped the lower jaw, creating an overbite. The jaws were relatively narrow (especially in juveniles). The snout comprises about 75% of the skull's length.
The very largest Sarcosuchus is believed to have been the oldest. Osteoderm growth rings taken from an 80% grown individual (based on comparison to largest individual found) suggest that Sarcosuchus kept growing throughout its entire 50–60 year average life span. Modern crocodiles grow at a rapid rate, reaching their adult size in about a decade, then growing more slowly afterward.
Its skull alone was as big as a human adult (1.78 m, or 5 ft 10 inches). The upper jaw overlapped the lower jaw, creating an overbite. The jaws were relatively narrow (especially in juveniles). The snout comprises about 75% of the skull's length.
The huge jaw contained 132 thick teeth; Larsson said they were like "railroad spikes".[citation needed] Instead of being narrow and adapted for slashing like the teeth of some land-dwelling carnivores, the teeth were conical, adapted for grabbing and holding, more like those of true crocodilians, which normally dispatch prey simply by holding them underwater until they drown. Sarcosuchus could probably exert a force of 80 kN (18,000 lbf) with its jaw, making it very unlikely that prey could escape.It had a row of bony plates or osteoderms, running down its back, the largest of which were 1 m (3 ft) long. The scutes served as armour and may have helped support its great mass, but also restricted its flexibility.[citation needed]
Sarcosuchus also had a strange depression at the end of its snout. Called a bulla, it has been compared to the ghara seen in gharials. Unlike the ghara, though, the bulla is present in all Sarcosuchus skulls that have been found so far. This suggests it was not a sexually selected characteristic; only the male gharial has a ghara. The purpose of this structure remains enigmatic. Sereno and others asked various reptile researchers what their thoughts on this bulla were. Opinions ranged from it being an olfactory enhancer to being connected to a vocalization device.
The eye sockets of Sarcosuchus rotated upwards and were somewhat telescoped. This suggests that the animal probably spent most of its time with the majority of its body submerged, watching the shore for prey.
It seems likely that it ate the large fish and turtles of the Cretaceous. As the overhanging jaw and stout teeth are designed for grabbing and crushing, its primary prey may have been large animals and smaller dinosaurs, which it ambushed, dragged into the water, crushed, drowned and then tore apart.
It may have come into conflict with Suchomimus, an 11 m (36 ft) theropod dinosaur with a gharial-like snout, whose fossils were found in the same geological formation as Sarcosuchus. According to Sereno,[citation needed] "because the ancient animal was so large, it could easily handle huge dinosaurs, including the massive long-necked, small-headed sauropods that were common in that African region".
Other crocodilian biologists are skeptical of the animal's "giant killing" capabilities.[citation needed] The long, thin snout of Sarcosuchus was very similar to the thin snouts of the modern gharial, the false gharial and the slender-snouted crocodile, all of which are nearly exclusive fish-eaters and incapable of tackling large prey. This can be contrasted to both the modern Nile crocodile and the extinct Deinosuchus, both of which exhibit very broad, heavy skulls, suitable for dealing with large prey. This, coupled with the abundance of large, lobe-finned fish in its environment, leads many to suggest that, far from being a dinosaur killer, Sarcosuchus was simply a large piscivore, a scaled-up version of the modern gharial.
However, while the snout of juvenile Sarcosuchus strongly resembled modern narrow-snouted crocodiles in width, it expands dramatically in mature individuals. While still comparatively narrower than the snout of a Nile crocodile, the snout is still much wider than the snouts of crocodilians like the gharial. In addition, the teeth do not interlock,[citation needed] like those of mostly piscivorous crocodilians. This suggests that, like the Nile crocodile, it may have complemented a primarily fish diet with terrestrial animals, at least upon maturity.[citation needed]
It is pertinent to note, though, that the lobe-finned fish that shared the waters with Sarcosuchus were often in excess of 1.8 m (6 ft) long and 90 kg (200 lb) in weight.[citation needed] This raises the possibility of those adaptations, which seem to indicate large or moderate-sized terrestrial prey, may instead have been adaptations for dealing with exceptionally large fish (many species of which possessed a layer of osteoderms, for protection).
It seems likely that it ate the large fish and turtles of the Cretaceous. As the overhanging jaw and stout teeth are designed for grabbing and crushing, its primary prey may have been large animals and smaller dinosaurs, which it ambushed, dragged into the water, crushed, drowned and then tore apart.
It may have come into conflict with Suchomimus, an 11 m (36 ft) theropod dinosaur with a gharial-like snout, whose fossils were found in the same geological formation as Sarcosuchus. According to Sereno,[citation needed] "because the ancient animal was so large, it could easily handle huge dinosaurs, including the massive long-necked, small-headed sauropods that were common in that African region".
Other crocodilian biologists are skeptical of the animal's "giant killing" capabilities.[citation needed] The long, thin snout of Sarcosuchus was very similar to the thin snouts of the modern gharial, the false gharial and the slender-snouted crocodile, all of which are nearly exclusive fish-eaters and incapable of tackling large prey. This can be contrasted to both the modern Nile crocodile and the extinct Deinosuchus, both of which exhibit very broad, heavy skulls, suitable for dealing with large prey. This, coupled with the abundance of large, lobe-finned fish in its environment, leads many to suggest that, far from being a dinosaur killer, Sarcosuchus was simply a large piscivore, a scaled-up version of the modern gharial.
However, while the snout of juvenile Sarcosuchus strongly resembled modern narrow-snouted crocodiles in width, it expands dramatically in mature individuals. While still comparatively narrower than the snout of a Nile crocodile, the snout is still much wider than the snouts of crocodilians like the gharial. In addition, the teeth do not interlock,[citation needed] like those of mostly piscivorous crocodilians. This suggests that, like the Nile crocodile, it may have complemented a primarily fish diet with terrestrial animals, at least upon maturity.[citation needed]
It is pertinent to note, though, that the lobe-finned fish that shared the waters with Sarcosuchus were often in excess of 1.8 m (6 ft) long and 90 kg (200 lb) in weight.[citation needed] This raises the possibility of those adaptations, which seem to indicate large or moderate-sized terrestrial prey, may instead have been adaptations for dealing with exceptionally large fish (many species of which possessed a layer of osteoderms, for protection).
110 million years ago, in the Early Cretaceous, the Sahara was still a great tropical plain, dotted with lakes and crossed by rivers and streams that were lined with vegetation. Based on the number of fossils discovered, the aquatic Sarcosuchus was probably plentiful in these warm, shallow, freshwater habitats.
Unlike modern true crocodiles, which are very similar in size and shape to one another and tend to live in different areas; Sarcosuchus was just one of many Crocodyliformes, of different sizes and shapes, all living in the same area. Four other species of extinct Crocodyliformes were also discovered in the same rock formation along with the Sarcosuchus, including a dwarf crocodile with a tiny, 8 cm (3 in) long skull. They filled a diverse variety of ecological niches, instead of competing with each other for resources.
Unlike modern true crocodiles, which are very similar in size and shape to one another and tend to live in different areas; Sarcosuchus was just one of many Crocodyliformes, of different sizes and shapes, all living in the same area. Four other species of extinct Crocodyliformes were also discovered in the same rock formation along with the Sarcosuchus, including a dwarf crocodile with a tiny, 8 cm (3 in) long skull. They filled a diverse variety of ecological niches, instead of competing with each other for resources.
Giant crocodiles seem to be a good example of convergence because, according to Schwimmer, "the idea of really big crocs is a repeat theme in evolution". This may in part be due to body design and in part due to environment: The armoured plates of the back can provide structural support to a massive body), and water can buoy up their massive bodies.
A study of another giant crocodilian, Deinosuchus, indicated that it grew at about the same rate as modern crocodiles, up to 0.5 m (1.5 ft) per year. It was larger, because it kept growing, reaching full adulthood in 35 years, instead of 10. While there is a genetic component, growing that large also requires a rich diet. All the different giant crocodiles must have lived in near-perfect environments, with vast areas of warm, shallow water and abundant prey.
Deinosuchus, which was from the Late Cretaceous of what is now North America, is also a good example of a giant crocodile that is only distantly related to Sarcosuchus. Deinosuchus, which is only known from skulls, had a smaller skull than Sarcosuchus,[citation needed] but a broad snout, like an alligator. This means that the skull of the Deinosuchus is probably a smaller portion of its total body length than the skull of the long-snouted Sarcosuchus, so its total size may be as large, or even larger.[citation needed] Other rivals in size of Sarcosuchus are Purussaurus from the Miocene of what is now Peru and Brazil, and Rhamphosuchus from the Miocene and Pliocene of what is now India. However, their fossils are less complete.
A study of another giant crocodilian, Deinosuchus, indicated that it grew at about the same rate as modern crocodiles, up to 0.5 m (1.5 ft) per year. It was larger, because it kept growing, reaching full adulthood in 35 years, instead of 10. While there is a genetic component, growing that large also requires a rich diet. All the different giant crocodiles must have lived in near-perfect environments, with vast areas of warm, shallow water and abundant prey.
Deinosuchus, which was from the Late Cretaceous of what is now North America, is also a good example of a giant crocodile that is only distantly related to Sarcosuchus. Deinosuchus, which is only known from skulls, had a smaller skull than Sarcosuchus,[citation needed] but a broad snout, like an alligator. This means that the skull of the Deinosuchus is probably a smaller portion of its total body length than the skull of the long-snouted Sarcosuchus, so its total size may be as large, or even larger.[citation needed] Other rivals in size of Sarcosuchus are Purussaurus from the Miocene of what is now Peru and Brazil, and Rhamphosuchus from the Miocene and Pliocene of what is now India. However, their fossils are less complete.
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