How large was the Smilodon?
Smilodon
Overall, "Smilodon" was more robustly built than any extant cat, with particularly well-developed forelimbs and exceptionally long upper canine teeth. Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing. "S. gracilis" was the smallest species at in weight. "S. fatalis" had a weight of and height of . Both of these species are mainly known from North America, but remains from South America have also been attributed to them. "S. populator" from South America was the largest species, at in weight and in height, and was among the largest known felids. The coat pattern of "Smilodon" is unknown, but it has been artistically restored with plain or spotted patterns.
Machairodus
"Machairodus" was similar in size to a modern lion, standing about at the shoulder. The species once referred to "Machairodus coloradensis" was apparently significantly larger, about at the shoulder, according to skeletal and life reconstructions. If accurate, this would have made "M. coloradensis" one of the largest felids. However "M. coloradensis", along with "M. kurteni" and "M. giganteus", has been reassigned to the genus "Amphimachairodus" and by extent, the Homotherini based on both morphology and its time of appearance in North America. "Nimravides catacopsis" also has been separated from "Machairodus", as the two are too different in regards to autapomorphies to be synonymous. However, the species "Machairodus horribilis", which stands as the largest known species of the genus, is comparable in size to the much later "Smilodon populator", weighing in at around . Its skull, measuring upwards of in length, is the largest known skull for any machairodont.
Cimolodon
"Cimolodon electus" (Fox R.C. 1971) is known from the Upper Cretaceous of the Upper Milk River Formation in Alberta, Canada. The holotype is in the collection of the University of Alberta. Possible finds have been reported from New Mexico. Weight is estimated at 19g, about half the weight of a modern rat.
Cimolodon
"Cimolodon similis" (Fox R.C. 1971) is known from the Upper Cretaceous of Utah. This holotype is also in the University of Alberta. It had a body weight around 125 g, about five standard mice.
Stegodon
A review of 130 papers written about 180 different sites with proboscidean remains in southern China revealed "Stegodon" to have been more common than Asian elephants; the papers gave many recent radiocarbon dates, the youngest being 2,150 BCE (4,100 BP). However, Turvey "et al." (2013) reported that one of the faunal assemblages including supposed fossils of Holocene "Stegodon" (from Gulin, Sichuan Province) is actually late Pleistocene in age; other supposed fossils of Holocene stegodonts were lost and their age cannot be verified. The authors concluded that the latest confirmed occurrences of "Stegodon" from China are from the late Pleistocene, and that its Holocene survival cannot be substantiated. 
"Stegodon" was one of the largest proboscideans, along with more derived genera. "S. zdansky" is known from an old male (50+) from the Yellow River that is tall and would have weighed approximately in life. It had a humerus long, a femur long, and a pelvis wide.
HSwMS Sköld
HSwMS "Sköld" was the second of these monitors. She was designed by the inventor John Ericsson
and Lieutenant John Christian d'Ailly. "Sköld" measured long overall and had a beam of . She had a draft of and displaced . Her crew initially numbered 40 officers and men, but it was reduced to 29 when the rowing mechanism was removed early in the ship's career.
Liger
Ligers are about the same size as the prehistoric "Smilodon populator" and American lion.
Cephalopod size
For total length, Paxton (2016a:83) considered three records as candidates for the "longest measured": the specimen of Berzin (1972:199), the specimen described by Kirk (1888) as "Architeuthis longimanus"—a strangely proportioned animal that has been much commented on—and the "Thimble Tickle specimen" reported by Verrill (1880a:191), which is often cited as the largest giant squid ever recorded. Of the last one, Paxton wrote: "Sometimes mistakenly cited as 17.37 m (57 ft) but the source is clear that it is 55 ft long." The first two records, particularly that of Berzin, are more questionable, as Paxton explained:
Amygdalodon
"Amygdalodon" is estimated to have been long and tall. This quadrupedal dinosaur had an estimated weight of over .
911 Agamemnon
911 Agamemnon ( ), provisional designation "", is a large Jupiter trojan and a suspected binary asteroid from the Greek camp, approximately in diameter. It was discovered on 19 March 1919, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The dark D-type asteroid is one of the largest Jupiter trojans and has a rotation period of 6.6 hours. It is named after the Greek King Agamemnon, a main character of the "Iliad".
First American Cave
Radiocarbon analysis of human remains from the cave returned dates of 2390+/-145 B.P. and 1690+/-115 B.P., placing them within the Woodland period of regional prehistory. Portions of these burials were identified in situ approximately 16-feet above the depth of the bones of the saber-toothed cat. According to Guilday, collagen from the "Smilodon" remains returned radiocarbon dates of 9410+/-155 B.P. and 10,035+/-650 B.P. These dates are extremely late for the presence of "Smilodon" in the Southeast, and are likely the result of sample contamination.
List of creatures in Primeval
"Smilodon" was mentioned in episode 1.4 by Helen Cutter as "sabre-toothed killers". However, she apparently lied when she claimed they would come through at that point, and escaped through the Spaghetti Junction. They are also seen, in skeleton form, in Nick's office.
Megalodon
Marine mammals attained their greatest diversity during the Miocene, such as with baleen whales with over 20 recognized Miocene genera in comparison to only six extant genera. Such diversity presented an ideal setting to support a super-predator such as megalodon. By the end of the Miocene, many species of mysticetes had gone extinct; surviving species may have been faster swimmers and thus more elusive prey. Furthermore, after the closure of the Central American Seaway, tropical whales decreased in diversity and abundance. The extinction of megalodon correlates with the decline of many small mysticete lineages, and it is possible that it was quite dependent on them as a food source. Additionally, a marine megafauna extinction during the Pliocene was discovered to have eliminated 36% of all large marine species including 55% of marine mammals, 35% of seabirds, 9% of sharks, and 43% of sea turtles. The extinction was selective for endotherms and mesotherms relative to poikilotherms, implying causation by a decreased food supply and thus consistent with megalodon being mesothermic. Megalodon may have been too large to sustain itself on the declining marine food resources. The cooling of the oceans during the Pliocene might have restricted the access of megalodon to the polar regions, depriving it of the large whales which had migrated there.
Cephalopod size
Squids are the largest living cephalopods in terms of each of mantle length, total length, and mass, with the largest species by at least two of these measures being the colossal squid, "Mesonychoteuthis hamiltoni". Reaching an estimated in mantle length and in total length, and weighing as much as , this species is also the largest of all extant invertebrates (Rosa & Seibel, 2010; McClain "et al.", 2015; Rosa "et al.", 2017). The only other squid that approaches these dimensions is the giant squid of the genus "Architeuthis", with females up to , in mantle length, and possibly as much as in total length, making it likely the longest of all cephalopods (McClain "et al.", 2015). The two largest octopus species—"Enteroctopus dofleini" and "Haliphron atlanticus"—can both exceed , and the former has a maximum total length of more than . Cirrate (finned) octopods can also reach a large size, with the largest captured specimen likely being a "Cirrothauma magna" of total length and mantle length (Collins "et al.", 2001; Collins & Villanueva, 2006:294), though observations from submersibles suggest that members of this group can exceed in total length (Voss, 1988; Vecchione "et al.", 2008). Members of the other cephalopod groups are substantially smaller, although the largest cuttlefish can exceed in weight and in mantle length. Cephalopods of comparable size to the largest present day squid are known from fossil remains, including enormous examples of ammonoids, belemnoids, nautiloids, orthoceratoids, teuthids, and vampyromorphids (see Teichert & Kummel, 1960; Stevens, 1988; Eyden, 2003b; Larson, 2010; Iba "et al.", 2015).
Smilodon
A 2017 study indicates that juveniles were born with a robust build similar to the adults. Comparison of the bones of juvenile "S. fatalis" specimens from La Brea with those of the contemporaneous American lion revealed that the two cats shared a similar growth curve. Felid forelimb development during ontogeny (changes during growth) has remained tightly constrained. The curve is similar to that for modern cats such as tigers and cougars, but shifts more towards the robust direction of the axes than is seen in modern felids.
Pyramiden
Pyramiden was founded by Sweden in 1910 and sold to the Soviet Union in 1927. It lies at the foot of the Billefjorden on the island of Spitsbergen and is named after the pyramid-shaped mountain with the same name adjacent to the town. The nearest settlements are Svalbard's capital, Longyearbyen, some to the south, Barentsburg approximately south-west and the small research community of Ny-Ålesund, to the west. In Soviet times population of the town was mostly Ukrainian, consisting of miners from Donbass and staff from Volyn.
Vulcanodon
"Vulcanodon" was a small sauropod. In 2010, Gregory S. Paul estimated its length at eleven metres, its weight at 3.5 tonnes. Some books mention lower estimates of approximately . The thighbone was 110 centimeters long.
Smilodon
Long the most completely known saber-toothed cat, "Smilodon" is still one of the best-known members of the group, to the point where the two concepts have been confused. The term "saber-tooth" refers to an ecomorph consisting of various groups of extinct predatory synapsids (mammals and close relatives), which convergently evolved extremely long maxillary canines, as well as adaptations to the skull and skeleton related to their use. This includes members of Gorgonopsia, Thylacosmilidae, Machaeroidinae, Nimravidae, Barbourofelidae, and Machairodontinae. Within the family Felidae (true cats), members of the subfamily Machairodontinae are referred to as saber-toothed cats, and this group is itself divided into three tribes: Metailurini (false saber-tooths); Homotherini (scimitar-toothed cats); and Smilodontini (dirk-toothed cats), to which "Smilodon" belongs. Members of Smilodontini are defined by their long slender canines with fine to no serrations, whereas Homotherini are typified by shorter, broad, and more flattened canines, with coarser serrations. Members of Metailurini were less specialized and had shorter, less flattened canines, and are not recognized as members of Machairodontinae by some researchers.
Lepidoteuthis grimaldii
Lepidoteuthis grimaldii, also known as the Grimaldi scaled squid, is a large squid growing to 1 m in mantle length. It is named after the Grimaldi family, reigning house of Monaco. Prince Albert I of Monaco was an amateur teuthologist who pioneered the study of deep sea squids by collecting the 'precious regurgitations' of sperm whales. The Grimaldi scaled squid was first collected from the stomach contents of a sperm whale. It is a widely distributed species in tropical and subtropical areas of the North and South Atlantic, the southern Indian Ocean and the Pacific Ocean, where it has been recorded off Japan and in the west Pacific.
Smilodontini
Smilodontini is an extinct tribe within the Machairodontinae or "saber-toothed cat" subfamily of the Felidae. The tribe is also known as the "dirk-toothed cats". They were endemic to South America, North America, Europe, Asia, and Africa during the Miocene to Pleistocene, from 10.3 mya—11,000 years ago, existing for approximately .
Squalodontidae
With their cosmopolitan Miocene distribution and heterodont dentition, squalodontids are the most common and basal platanistoids. They are relatively large odontocetes, comparable in size to extant mesoplodont whales. The premaxillae on their elongated rostrum have large and slightly convex fossae for the air sacs associated with the presence of a melon, indicating the ability for echolocation.
Smilodon
Along with most of the Pleistocene megafauna, "Smilodon" became extinct 10,000 years ago in the Quaternary extinction event. Its extinction has been linked to the decline and extinction of large herbivores, which were replaced by smaller and more agile ones like deer. Hence, "Smilodon" could have been too specialized at hunting large prey and may have been unable to adapt. A 2012 study of "Smilodon" tooth wear found no evidence that they were limited by food resources. Other explanations include climate change and competition with humans (who entered the Americas around the time "Smilodon" disappeared), or a combination of several factors, all of which apply to the general Pleistocene extinction event, rather than specifically to the extinction of the saber-toothed cats.
Smilodon
Many "Smilodon" specimens have been excavated from asphalt seeps that acted as natural carnivore traps. Animals were accidentally trapped in the seeps and became bait for predators that came to scavenge, but these were then trapped themselves. The best-known of such traps are at La Brea in Los Angeles, which have produced over 166,000 "Smilodon fatalis" specimens that form the largest collection in the world. The sediments of the pits there were accumulated 40,000 to 10,000 years ago, in the Late Pleistocene. Though the trapped animals were buried quickly, predators often managed to remove limb bones from them, but they were themselves often trapped and then scavenged by other predators; 90% of the excavated bones belonged to predators.
Smilodon
"Smilodon" started developing its adult saber-teeth when the animal turned one-and-a-half years of age, shortly after the completion of the eruption of the cat's baby teeth. Both baby and adult canines would be present side by side in the mouth for an 11-month period, and the muscles used in making the powerful bite were developed at about one-and-a-half years old as well, eight months earlier than in a modern lion. After "Smilodon" turned around 20 months of age, the infant teeth were shed while the adult canines grew at an average growth rate of per month during a 12-month period. They reached their full size at around 3 years of age, later than for modern species of big cat. Juvenile and adolescent "Smilodon" specimens are extremely rare at Rancho La Brea, where the study was performed, indicating that they remained hidden or at denning sites during hunts, and depended on parental care while their canines were developing.
Hughmilleria
"Hughmilleria" is the most basal (primitive) known member of the Pterygotioidea. It was a small-sized eurypterid, with the largest specimen measuring 20 cm (8 in), being surpassed by other members of its superfamily, such as "Slimonia acuminata", which measured 100 cm (39 in) in length, and "Pterygotus grandidentatus", which could reach 1.75 meters (5 ft 8 in). The telson (the most posterior segment of the body), which was lanceolate and styliform, is distinctly a "Eurypterus"-like feature. The marginal compound eyes, the relatively large chelae and the cordate (heart-shaped) metastoma (a large plate that is part of the abdomen) show a great resemblance to "Pterygotus". The carapace was parabolic or subquadrate with oval marginal eyes, the chelicerae were able to extend beyond the carapace margin and the appendages II–V were spiniferous. The genus is in various ways similar to the more derived eurypterids of its superfamily, the Pterygotioidea, however, it lacked the expanded and flattened telson that the pterygotids and "Slimonia" had. This suggests that "Hughmilleria" did not need to use the telson as a rudder to swim.
Spinosaurus
"Spinosaurus" was among the largest of all known carnivorous dinosaurs, nearly as large as or even larger than "Tyrannosaurus", "Giganotosaurus" and "Carcharodontosaurus". Estimates published in 2005, 2007, and 2008 suggested that it was between in length and in weight. New estimates published in 2014 and 2018 based on a more complete specimen, supported the earlier research, finding that "Spinosaurus" could reach lengths of . The latest estimates suggest a weight of . The skull of "Spinosaurus" was long and narrow, similar to that of a modern crocodilian. "Spinosaurus" is known to have eaten fish, and most scientists believe that it hunted both terrestrial and aquatic prey; evidence suggests that it lived both on land and in water as a modern crocodilian does. The distinctive spines of "Spinosaurus", which were long extensions of the vertebrae, grew to at least long and were likely to have had skin connecting them, forming a sail-like structure, although some authors have suggested that the spines were covered in fat and formed a hump. Multiple functions have been put forward for this structure, including thermoregulation and display.
Machairodontinae
Traditionally, three different tribes of machairodontines were recognized, the Smilodontini with typical dirk-toothed forms, such as "Megantereon" and "Smilodon", the Machairodontini or Homotherini with scimitar-toothed cats, such as "Machairodus" or "Homotherium", and the Metailurini, containing genera such as "Dinofelis" and "Metailurus". However, some have recently regrouped the Metailurini within the other felid subfamily, the Felinae, along with all modern cats. The last machairodontine genera, "Smilodon" and "Homotherium", did not disappear until late in the Pleistocene, roughly 10,000 years ago in the Americas.
Giant
The Bible also tells of Gog and Magog, who later entered European folklore, and of the famous battle between David and the Philistine Goliath. While Goliath is often portrayed as a giant in retellings of the Biblical narrative, he is much smaller than other biblical giants. The 1st-century Jewish historian Flavius Josephus, and the 1st-2nd-century BC Dead Sea Scrolls give Goliath's height as "four cubits and a span," approximately 2.00 m or about six feet seven inches. The King James translation of the Bible reports the giant Goliath as "six cubits and a span" in height—about nine feet nine inches tall, (over 2.75 m) ( KJV), but the Septuagint, a Greek Bible, gives Goliath's height as "four cubits and a span" (~2.00 m). For comparison, the Anakites are described as making the Israelites seem like grasshoppers. See also Gibborim.
Homotherium
The lineage of "Homotherium" is estimated (based on mitochondrial DNA sequences) to have diverged from that of "Smilodon" about 18 million years ago. "Homotherium" probably derived from "Machairodus" and appeared for the first time at the Miocene–Pliocene border, about 4 to 5 million years ago. During the Pleistocene it occurred in vast parts of Eurasia, North America and until the middle Pleistocene (about 1.5 million years ago) even in Africa. A fossil of "H. crenatidens" was inadvertently dredged from the bed of the North Sea, which was a flat, low-lying extent of marshy tundra laced with rivers during the last glacial period. There has also been a discovery of 1.8-million-year-old fossils in Venezuela, indicating that scimitar-toothed cats were able to invade South America along with "Smilodon" during the Great American Interchange. These remains form the holotype of "Homotherium venezuelensis". How long they lasted in South America is not yet evident. "Homotherium" survived in Eurasia until about 28,000 years ago.
St. Louis Museum
A museum specimen of particular note was a fossil, the Zeuglodon, which the Complete Guide to the St. Louis Museum called "the greatest fossil in the world." The Zeuglodon was discovered in 1848 in a field in Alabama. After it was extricated from the rock in which it was found, Dr. Koch purchased the fossil for the St. Louis Museum. The fossilized animal was amphibious and resembled a whale, alligator, and serpent. Only one other fossil of this animal was known to exist at the time, which was owned by the King of Prussia. Previously a Mastodon fossil was the largest one discovered, at 20 feet. The Zeuglodon measured 96 feet. Though some doubted the authenticity of the specimen, Professor Joseph Leidy, M.D. of the University of Pennsylvania and Curator of the Academy of Natural Sciences of Philadelphia and Professor Silliman of Yale College both attested to the authenticity of the fossil.
Machairodontinae
Until the recent discovery of the Late Miocene fossil depository known as Batallones-1 in the 1990s, specimens of Smilodontini and Homotheriini ancestors were rare and fragmentary, so the evolutionary history of the saber-toothed phenotype, a phenotype affecting craniomandibular, cervical forelimb and forelimb anatomy, was largely unknown. Prior to the excavation of Batallones-1, the predominating hypothesis was that the highly derived saber-toothed phenotype arose rapidly through pleiotropic evolution. Batollnes-1 unearthed new specimens of "Promegantereon ogygia", a Smilodontini ancestor, and "Machairodus aphanistus", a Homotheriini ancestor, shedding light on evolutionary history. (Though the Smilodontini ancestor was originally assigned to the genus "Paramachairodus", it was later revised to the genus "Promegantereon"). The leopard-sized "P. ogygia" (living 9.0 Ma) inhabited Spain (and perhaps additional territory), and its most studied descendants, the members of the tiger-sized genus "Smilodon", lived up to 10,000 years ago in the Americas. The lion-sized "M. aphanistus" (living 15.0 Ma) roamed Eurasia, as did its most studied descendants, members of the lion-sized genus "Homotherium" (living 3.0-5.0 Ma).
Kopidodon
Kopidodon is a genus of extinct squirrel-like mammals belonging to the order Cimolesta. "Kopidodon" was one of the largest tree-dwelling mammals known from Eocene Europe: growing 115 centimeters long (most of that length is tail). This mammal sported large canine teeth, probably for defense. However its molars were adapted for chewing plants, not flesh. Its legs and claws allowed "Kopidodon" to scramble through the trees with the greatest of ease, much like modern-day squirrels. Its fossils were found in the Messel pit, preserving even its fur. We know that like a giant squirrel, "Kopidodon" had a thick bushy tail for balance.
Rhabdodon
"Rhabdodon" was probably an important herbivore in Cretaceous Europe. "Rhabdodon's" predators may include the potentially dubious abelisaur "Tarascosaurus", and young may have been prey for "Pyroraptor"; thought adults where probably too big for either; as "Tarascosaurus" was around 2.5–3 m (7–10 ft), "Pyroraptor" around 2 m (6–7 ft), and "Rhabdodon" 6 m (18–20 ft).
1713 Bancilhon
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Bancilhon" measures 5.716 kilometers in diameter and its surface has an albedo of 0.259, which is rather typical for asteroids with stony composition. It has an absolute magnitude of 13.3. As of 2017, "Bancilhon"s spectral type, rotation period and shape remain unknown.
Slimonia
Out of the four described species of "Slimonia", three measured below or up to in length. Only "S. acuminata" was larger, with the largest specimens measuring in length. Though this is large for a predatory arthropod, "Slimonia" would be exceeded in length by later and more derived (more "advanced") members of the closely related pterygotid family of eurypterids, which would become the largest known arthropods to ever live.
Stegodon
Similar to modern-day elephants, stegodonts were likely good swimmers, as their fossils are frequently encountered on Asian islands (such as Sulawesi, Flores, Timor, Sumba in Indonesia; Luzon and Mindanao in the Philippines; Taiwan; and Japan), all locations not connected by land bridges with the Asian continent even during periods of low sea-level (during the cold phases of the Pleistocene). A general evolutionary trend in large mammals on islands is island dwarfing. The smallest dwarf species, "S. sondaari", known from 900,000-year-old layers on the Indonesian island of Flores, had an estimated body weight of , smaller than a water buffalo. Another estimate gives a shoulder height of and a weight of . A medium- to large-sized stegodont, "S. florensis", with a body weight of about , appeared about 850,000 years ago, and then also evolved into a dwarf form, "Stegodon florensis insularis". Another estimate gives a shoulder height of and a weight of . The latter was contemporaneous with, and hunted by, the dwarf hominin "Homo floresiensis", and disappeared about 12,000 years ago.
It is also believed that dwarf stegodons were the main prey of the still-extant Komodo dragon before modern humans introduced their modern main prey in its range, banded pig, rusa deer and water buffalo.
Megalodon
While the earliest megalodon remains were reported from the Late Oligocene dated to around 28 million years ago (mya), competing figures still exist as to when it evolved, such as 16 mya and 23 mya. It is believed that megalodon became extinct around the end of the Pliocene, probably about 2.6 mya; reported Pleistocene megalodon teeth, younger than 2.6 million years old, are considered to be unreliable claims.
Cephalopod size
Perhaps the largest of all recorded giant squid specimens was the one found floating at the surface off Saint-Gilles, Réunion, on 4 March 2016 (Romanov "et al.", 2017). Although due to its great size the specimen could not be retrieved in its entirety, the head and arm crown were saved. Crucially, this meant the beak could be measured to estimate the mantle length and total length of the specimen. Using different allometric scaling equations, the lower rostral length of the beak, at , gave an estimated dorsal mantle length of and this, in turn, was used to estimate the total length at (Romanov "et al.", 2017).
Smilodon
Traditionally, saber-toothed cats have been artistically restored with external features similar to those of extant felids, by artists such as Charles R. Knight in collaboration with various paleontologists in the early 20th century. In 1969, paleontologist G. J. Miller instead proposed that "Smilodon" would have looked very different from a typical cat and similar to a bulldog, with a lower lip line (to allow its mouth to open wide without tearing the facial tissues), a more retracted nose and lower-placed ears. Paleoartist Mauricio Antón and coauthors disputed this in 1998 and maintained that the facial features of "Smilodon" were overall not very different from those of other cats. Antón noted that modern animals like the hippopotamus are able to achieve a wide gap without tearing tissue by the moderate folding of the orbicularis oris muscle, and such a muscle configuration exists in modern large felids. Antón stated that extant phylogenetic bracketing (where the features of the closest extant relatives of a fossil taxon are used as reference) is the most reliable way of restoring the life-appearance of prehistoric animals, and the cat-like "Smilodon" restorations by Knight are therefore still accurate.
Sucuriju gigante
Sucuriju gigante (giant , giant boa, or giant anaconda) is a legendary giant snake, an Amazon rainforest constrictor described as up to long, around, and weighing up to 5 tons. It is sometimes described as horned. Some tribes from the Amazon speak of sucuri gigante as the anaconda, referring to it as the creator of the Amazon River. It is also referred to as "Mysterious Beast" and "Controller", as it is said to control the areas of the rivers it inhabits. A sub-species of the common green anaconda "(Eunectes murinus)" has been suggested as the origin of the legend, but some speculation has proposed that it could be a descendant of "Gigantophis", a large snake from the Eocene period, (58 million to 34 million years BPE) that could reach in length.
Megalodon
Megalodon ("Carcharocles megalodon"), meaning "big tooth", is an extinct species of shark that lived approximately 23 to 2.6 million years ago (mya), during the Early Miocene to the end of the Pliocene. It was formerly thought to be a member of the Lamnidae family, making it closely related to the great white shark ("Carcharodon carcharias"). However presently there is near unanimous consensus that it belongs to the extinct family Otodontidae, which diverged from the ancestry of the great white shark during the Early Cretaceous. Its genus placement is still debated, authors placing it in either "Carcharocles", "Megaselachus", "Otodus", or "Procarcharodon".
Euthecodon
"Euthecodon" was large for a crocodilian. One specimen, LT 26306, found from the Turkana Basin, was estimated by skull length to have been around 10 m long. It had a narrow rostrum that was unusually elongate with deeply scalloped dorsal margins. The skull table, however, was proportionally small and is almost square in shape. The jaws were lined with isodont, or slender, similarly sized and shaped, teeth. Unlike nearly all other crocodilians, "Euthecodon" possessed only four premaxillary teeth. Because they are sharp and bicarinate, they are believed to have been an adaptation for a piscivorous feeding habit, or a diet that included fish.
Smilodon
Despite being more powerfully built than other large cats, "Smilodon" had a weaker bite. Modern big cats have more pronounced zygomatic arches, while these were smaller in "Smilodon", which restricted the thickness and therefore power of the temporalis muscles and thus reduced "Smilodon"'s bite force. Analysis of its narrow jaws indicates that it could produce a bite only a third as strong as that of a lion (the bite force quotient measured for the lion is 112). There seems to be a general rule that the saber-toothed cats with the largest canines had proportionally weaker bites. Analyses of canine bending strength (the ability of the canine teeth to resist bending forces without breaking) and bite forces indicate that the saber-toothed cats' teeth were stronger relative to the bite force than those of modern big cats. In addition, "Smilodon"'s gape could have reached almost 120 degrees, while that of the modern lion reaches 65 degrees. This made the gape wide enough to allow "Smilodon" to grasp large prey despite the long canines. A 2018 study compared the killing behaviour of "Smilodon fatalis" and "Homotherium serum", and found that the former had a strong skull with little trabecular bone for a stabbing canine-shear bite, whereas the latter had more trabecular bone and used a clamp and hold style more similar to lions. The two would therefore have held distinct ecological niches.
Saltriovenator
Because of the fragmentary nature of the remains, it was impossible to directly measure the size of the animal. The describing authors therefore compared the fossils with those of two theropods of a roughly similar volume. Comparing with the skeletal elements of MOR 693, a "Allosaurus fragilis" specimen, they conservatively concluded that the "Saltriovenator" holotype individual was at least seven to eight metres long. This would make "Saltriovenator" the largest known theropod living before the Aalenian stage, 25% longer than "Ceratosaurus" from the late Jurassic. Comparing with "Ceratosaurus" itself, resulted in a body length of 730 centimetres, a hip height of 220 centimetres and a skull length of eighty centimetres. The thighbone length would then have been about eighty to eighty-seven centimetres, which indicates a body weight of 1160 to 1524 kilogrammes. Another method consisted in extrapolating from the known length of the forelimb. Applying the usual limb ratio indicated a hindlimb length of 198 centimetres. The thighbone would then have been 822 to 887 millimetres long, indicating a weight of 1269 to 1622 kilogrammes.
American lion
The American lion is estimated to have measured from the tip of the nose to the base of the tail and stood at the shoulder. Thus, it was smaller than its contemporary competitor, the giant short-faced bear, which was the largest carnivoran of North America at the time, and larger than the saber-toothed cat, "Smilodon fatalis", which may have weighed up to . In 2008, the American lion was estimated to weigh up to . A study in 2009 showed an average weight of for males and for the largest specimen analyzed. A study in 2012 estimated a range of for males and for females, which suggests that the lion was heavier than "Smilodon".
Megalodon
Megalodon were contemporaneous with whale-eating toothed whales (particularly macroraptorial sperm whales and squalodontids), which were also probably among the era's apex predators, and provided competition. Some attained gigantic sizes, such as "Livyatan", which grew from . By the Late Miocene, around 11 mya, macroraptorials experienced a significant decline in abundance and diversity. Other species may have filled this niche in the Pliocene, such as the fossil killer whale "Orcinus citoniensis" which may have been a pack predator and targeted prey larger than itself, although it was probably a generalist predator rather than a marine mammal specialist.
1527 Malmquista
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Malmquista" measures between 9.55 and 10.338 kilometers in diameter and its surface has an albedo between 0.220 and 0.307. The "Collaborative Asteroid Lightcurve Link" assumes an albedo of 0.24 – derived from 8 Flora, a S-type asteroid and the family's largest member and namesake – and calculates a diameter of 10.80 kilometers with an absolute magnitude of 12.0.
Simocyon
Simocyon (“short-snouted dog”) is a genus of extinct carnivoran mammal in the family Ailuridae. "Simocyon", which was about the size of a mountain lion, lived in the late Miocene and early Pliocene epochs, and has been found in Europe, Asia, and, rarely, North America (Peigné et al., 2005) and Africa.
Kollikodon
Like "Steropodon", "Kollikodon" was a relatively large mammal for the Mesozoic. The molars have a length of around 5.5 mm and a width of between about 4 and 6 mm (Clemens et al., 2003). Based upon these data, the potential body length could be up to a metre. Assuming the accuracy of such a guess, "Kollikodon" would be a contender for the largest Mesozoic mammal known, along with other possible giants such as "Repenomamus", "Schowalteria", and "Bubodens".
Mineral and Lapidary Museum
As for fossils and paleontology, the Mineral and Lapidary Museum has a replica Tyrannosaurus rex skull from the Cretaceous period of the Mesozoic era. Another skull is that of Smilodon, the big sabre-tooth cat from the Pleistocene epoch of the Cenozoic era—not to overlook a replica tusk and femur from a prehistoric mastodon.
Smilodon
Some early writers theorized that the last saber-toothed cats, "Smilodon" and "Homotherium", became extinct through competition with the faster and more generalized felids that replaced them. It was even proposed that the saber-toothed predators were inferior to modern cats, as the ever-growing canines were thought to inhibit their owners from feeding properly. Yet fast felids, such as the American lion and the American cheetah, also became extinct during the Late Pleistocene. The fact that saber-teeth evolved many times in unrelated lineages also attests to the success of this feature.
Pyramidion
The pyramidion of the scribe Moses (mes,s, New Kingdom, 19th Dynasty, c. 1250 BC, "limestone", 53 cm tall) depicts himself making an offering, with his name on two opposite faces. The adjacent opposite faces feature a baboon: "Screeching upon the rising of the Sun, and the Day". (The baboon is also the god-scribe representation of the Scribe, for the god Thoth.)
Haldanodon
"Haldanodon" was about the size of a desman in length, and may have had a similar ecology. The skull of "Haldanodon" is well known, and there is a little of the limbones also preserved. The body was compact and the legs were short and robust. The articulation of the distal humerus was particularly expanded, indicating strong muscles for either digging or swimming. The first front paws were relatively short, and the bones were curved and laterally compressed. The roughness of the skull on the nasal bones has been suggested to indicate the presence of a shield of keratin on the head above the eyes. The jaws were robust; in particular, the mandible was equipped with a highly developed coronoid process, which is seen in close relatives of this group.
Squalodon
Species of "Squalodon" are odontocetes that lived during the early-middle Oligocene into the middle Miocene, about 33 to 14 million years ago. The genus "Squalodon" belongs to the order Odontoceti, the toothed whales. They are named after the shark "Squalus" because their cheek teeth look like the teeth of a squalus shark. The unique-looking squalodontids were likely distributed throughout the world in warm waters during the Oligocene and Miocene. Squalodontidae became extinct in the middle of the Miocene, leaving no descendants. Hypotheses of why this family lead to extinction have to deal with competition of other groups of dolphins as well as climate change.
Megalodon
As its range did not apparently extend into colder waters, megalodon may not have been able to retain a significant amount of metabolic heat, so its range was restricted to shrinking warmer waters. Fossil evidence confirms the absence of megalodon in regions around the world where water temperatures had significantly declined during the Pliocene. However, an analysis of the distribution of megalodon over time suggests that temperature change did not play a direct role in its extinction. Its distribution during the Miocene and Pliocene did not correlate with warming and cooling trends; while abundance and distribution declined during the Pliocene, megalodon did show a capacity to inhabit colder latitudes. It was found in locations with a mean temperature ranging from , with a total range of , indicating that the global extent of suitable habitat should not have been greatly affected by the temperature changes that occurred. This is consistent with evidence that it was a mesotherm.
Megalodon
Scientists suggest that megalodon looked like a stockier version of the great white shark, though it may have looked similar to the basking shark ("Cetorhinus maximus") or the sand tiger shark ("Carcharias taurus"). Regarded as one of the largest and most powerful predators to have ever lived, fossil remains of megalodon suggest that this giant shark reached a maximum length of with the average size being . Their large jaws could exert a bite force of up to . Their teeth were thick and robust, built for grabbing prey and breaking bone.
Mustelodon
"Mustelodon" had a length of approximately 80 cm (head to tail) and this carnivore superficially resembled the modern mongooses. "Mustelodon" fed on fruits, insects and smaller mammals like shrews. It is closely related to the more famous "Protictis" from the Paleocene of the United States (Wannagan Creek - South Dakota, San Juan Basin - New Mexico).
List of Middle-earth animals
The Lord of Eagles in the First Age, said in "The Silmarillion" to be the "mightiest of all birds that have ever been", with a wingspan of thirty fathoms (54.9 meters, or 180 feet) and a beak of gold. His name translates from Sindarin, an Elven tongue devised by Tolkien, as 'King of Eagles'; its cognate form in Quenya, another Elven language, is Sorontar. He led the eagles during most of their appearances in "The Silmarillion", and has a significant role of his own.
Late Cenozoic Ice Age
2.5 million years ago brought about the evolution of the earliest Smilodon species.
Sylviornis
A large proportion—up to 50% in some deposits—of the remains found were from juvenile animals. Thus, it has been theorized that "Sylviornis" had a clutch of at least two, more probably closer to 10 eggs, and that the average lifespan was not much more than 5–7 years, which would be extremely low for such a large bird. It was thought that the bird did not incubate its eggs but built a mound similar to the megapodes. Tumuli on the Île des Pins which were initially believed to be graves were found to contain no human remains or grave goods, and it has been hypothesized that they were in reality the incubation mounds of "Sylviornis". As these mounds are up to 5 m high and 50 m wide even after nearly four millennia, they seem too large to have been made by the giant scrubfowl ("Megapodius molistructor"), an extinct New Caledonian species of megapode. 
However, recent assessment of this bird as outside and not even particularly closely related to megapodes make the possibility that it was a mound-builder like them strictly unlikely.
Scelidosaurus
A full-grown "Scelidosaurus" was rather small compared to most later non-avian dinosaurs, but it was a medium-sized species in the Early Jurassic. Some scientists have estimated a length of 4 metres (13 ft). In 2010, Gregory S. Paul gave a body length of 3.8 metres (12.5 ft) and a weight of 270 kilogrammes. "Scelidosaurus" was quadrupedal, with the hindlimbs longer than the forelimbs. It may have reared up on its hind legs to browse on foliage from trees, but its arms were relatively long, indicating a mostly quadrupedal posture. A trackway from the Holy Cross Mountains of Poland shows a scelidosaur like animal walking in a bipedal manner, hinting that "Scelidosaurus" may have been more proficient at bipedalism than previously thought.
Squalodon
Squalodon is an extinct genus of whales endemic to Oligocene to Miocene, belonging to the family Squalodontidae. Named by Jean-Pierre Sylvestre de Grateloup in 1840, it was originally believed to be an iguanodontid dinosaur but has since been reclassified. The name "Squalodon" comes from "Squalus", a genus of shark. As a result, its name means "shark tooth."
Smilosuchus
Like all phytosaurs, "Smilosuchus" had the nostrils close to the top of its head. The rostral crest and nasal bulge supporting these raised nostrils was larger in "Smilosuchus" than in many other phytosaurs. Its skull was extremely large, up to 155 cm long, although estimates for the overall length vary from 7 to 12 metres. The jaws are very short and broad and the teeth are heterodont, with large tusks at the anterior of the mouth for impaling prey and more blade-like teeth for slicing flesh closer to the back of the mouth. The tusks are mounted on a bulge at the tip of the snout present in nearly all phytosaurs. Its squamosal processes are short and deep, indicating a powerful bite. This coupled with its large size (it is one of the largest known phytosaurs)suggests that it hunted large prey such as "Placerias."
SS Basildon
The ship was long, with a beam of and a depth of . She was propelled by a triple expansion steam engine that had cylinders of , and bore by stroke. The engine was built by Rankin & Blackmore Ltd, Greenock. She had a GRT of 1,058, with a NRT of 584 and a DWT of 1,410.
Smilodon
Several "Smilodon" fossils show signs of ankylosing spondylitis, hyperostosis and trauma; some also had arthritis, which gave them fused vertebrae. One study of 1,000 "Smilodon" skulls found that 30% of them had eroded parietal bones, which is where the largest jaw muscles attach. They also showed signs of microfractures, and the weakening and thinning of bones possibly caused by mechanical stress from the constant need to make stabbing motions with the canines. Bony growths where the deltoid muscle inserted in the humerus is a common pathology for a La Brea specimen, which was probably due to repeated strain when "Smilodon" attempted to pull down prey with its forelimbs. Sternum injuries are also common, probably due to collision with prey. Some bones also show evidence of having been bitten by other "Smilodon", with one skull showing an unhealed wound from a canine, seemingly fatal, and a scapula from the same site that had been pierced by a canine. The frequency of trauma in "S. fatalis" specimens was 4.3%, compared to 2.8% in the dire wolf, which implies the ambush predatory behavior of the former led to greater risk of injury than the pursuit predatory behavior of the latter. "Smilodon" remains exhibit relatively more shoulder and lumbar vertebrae injuries.
Thelodus
Thelodus is an extinct genus of thelodont agnathan that lived during the Silurian period. Fossils have been found in Europe, Asia and North America. Unlike many thelodonts, species of "Thelodus" are known not only from scales, but from impressions in rocks. Some species, such as the Canadian "T. inauditus", are thought to be comparable in size to other thelodonts, i.e., from 5 to 15 centimeters in length. The scales of the type species, "T. parvidens" ("syn. T. macintoshi") of Silurian Great Britain, however, reach the size of coins, and, if proportioned like other thelodonts, such as "Loganellia", the living animal would have been about one meter in length.
11264 Claudiomaccone
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Claudiomaccone" measures 3.203 kilometers in diameter and its surface has a high albedo of 0.432, while the "Collaborative Asteroid Lightcurve Link" assumes a standard albedo for stony S-type asteroids of 0.20 and calculates a diameter of 4.30 kilometers with an absolute magnitude of 14.2.
Megalodon
In 2002, paleontologist Kenshu Shimada of DePaul University proposed a linear relationship between tooth crown height and total length after conducting anatomical analysis of several specimens, allowing any sized tooth to be used. Shimada stated that the previously proposed methods were based on a less-reliable evaluation of the dental homology between megalodon and the great white shark, and that the growth rate between the crown and root is not isometric, which he considered in his model. Using this model, the upper anterior tooth possessed by Gottfried and colleagues corresponded to a total length of . Among the specimens found in the Gatún Formation of Panama, other shark researchers used this method and calculated a maximum length of for a specimen.
List of creatures in Primeval
A fully-grown "Smilodon" weighed approximately and had a short tail, powerful legs, and a large head. The cats have two huge canine teeth, about long, that are used to kill prey by suffocation. The jaws could open to about 120 degrees in order to use these fangs to deadly effect. They would die out due to climate change.
Slimonia
"Slimonia" is in many ways similar to the more derived (more "advanced") eurypterids of its superfamily, the Pterygotioidea. In particular, the expanded and flattened telson (the most posterior segment of the body) of "Slimonia" is similar to that of the pterygotid eurypterids and is a feature that "Slimonia" and the pterygotids only share with some derived hibbertopterid eurypterids (where the feature convergently evolved). The pterygotid telson was in general slightly larger than that of "Slimonia" and was more slender. The telson spike of "Slimonia" was much longer than any seen in the Pterygotidae (constituting just over half of the total telson length) however, serrated and ending in a fine point. The largest species of "Slimonia", "S. acuminata", reached a maximum length of 100 cm (39 in) whilst the smallest, "S. dubia", grew to 12 cm (5 in) in length. Though 100 cm is large for a predatory arthropod, "Slimonia" would be exceeded in length by later and more derived (more "advanced") members of the closely related pterygotid family of eurypterids, which would become the largest known arthropods to ever live.
Smilodon
"S. gracilis" entered South America during the early to middle Pleistocene, where it probably gave rise to "S. populator", which lived in the eastern part of the continent. "S. fatalis" also entered western South America in the late Pleistocene, and the two species were thought to be divided by the Andes mountains. However, in 2018, a skull of "S. fatalis" found in Uruguay east of the Andes was reported, which puts the idea that the two species were allopatric (geographically separated) into question. The American interchange resulted in a mix of native and invasive species sharing the prairies and woodlands in South America; North American herbivores included proboscideans, horses, camelids and deer, South American herbivores included toxodonts, litopterns, ground sloths, and glyptodonts. Native metatherian predators (including the saber-toothed thylacosmilids) had gone extinct by the Pliocene, and were replaced by North American carnivores such as canids, bears, and large cats.
1854 Skvortsov
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Skvortsov" measures between 9.60 and 10.27 kilometers in diameter, and its surface has an albedo of 0.203 to 0.252. The "Collaborative Asteroid Lightcurve Link" assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 8.97 kilometers with an absolute magnitude of 12.6.
Cimolodon
"Cimolodon nitidus" (Marsh O.C. 1889) is also known as "Allacodon lentus" (Marsh 1889); "Allacodon rarus" (Marsh 1892); "Cimolomys bellus" (Marsh 1889); "Cimolomys digona" (Marsh 1899); "Cimolomys gracilis" (Marsh 1889); "Cimolomys minutes"; "Cimolomys nitidus"; "Halodon serratus" (Marsh 1889); "Nanomyops minitus" (Marsh 1892); "Nanomys minitus" (Marsh 1889); and "Ptilodus serratus" (Gidley 1909). It is known from Upper Cretaceous strata of the Lance Formation of Wyoming, Utah, Montana and South Dakota (United States and Canada). It weighed about 230 g. Simpson referred this species to "C. gracilis" in 1929. Subsequently, it has been reallocated to "C. nitidus" by various authors, apparently beginning with Clemens in 1963.
Mastodon
Modern reconstructions based on partial and skeletal remains reveal that mastodons were very similar in appearance to elephants and, to a lesser degree, mammoths, though not closely related to either one. Compared to mammoths, mastodons had shorter legs, a longer body and were more heavily muscled, a build similar to that of the current Asian elephants. The average body size of the species "M. americanum" was around in height at the shoulders, corresponding to a large female or a small male; large males were up to in height. Among the largest male specimens, the 35-year-old AMNH 9950 was tall and weighed , while another was tall and weighed .
Machairodontinae
The question of sociality is still controversial. Strong support for the traditional concept of a solitary "Smilodon" is found in its brain. Most social predators, including humans, grey wolves, and lions, have brains that are slightly larger than those of their loner relatives. "Smilodon" had a relatively small brain, suggesting less ability for complex cooperative behaviors, such as hunting in groups. The high numbers of "Smilodon" in the tar pits is often dismissed as evidence for a social nature because the golden eagle, a species still extant, is solitary and yet is found in the pits in similar numbers. The social grey wolf and coyote lived in the region, but their fossils in the pits are rare.
Megalodon
The extinction of megalodon set the stage for further changes in marine communities. The average body size of baleen whales increased significantly after its disappearance, although possibly due to other, climate-related, causes. Conversely the increase in baleen whale size may have contributed to the extinction of megalodon, as they may have preferred to go after smaller whales; bite marks on large whale species may have come from scavenging sharks. Megalodon may have simply become coextinct with smaller whale species, such as "Piscobalaena nana". The extinction of megalodon had a positive impact on other apex predators of the time, such as the great white shark, in some cases spreading to regions where megalodon became absent.
Rhamphosuchus
Traditionally, many palaeontologists estimated that it was one of the largest, if not the largest crocodylian that ever lived, reaching an estimated length of . However, a more recent study suggests that the animal may have been 8–11 m in length, and therefore is not the largest known crocodylian. Another crocodylian, "Purussaurus", from the Miocene of Peru and Brazil, is known from an equally incomplete fossil set. It is estimated to have been similar in length to the initial estimates at approximately 12 m. However, this would mean that it would have been somewhat larger in size if the more recent size estimates for "Rhamphosuchus" are correct. If the most recent estimate is correct, then several other extinct crocodylians also surpassed "Rhamphosuchus" in length, such as the Late Cretaceous alligatoroid "Deinosuchus", the Early Cretaceous pholidosaurid "Sarcosuchus", the Miocene gavialid "Gryposuchus" and the strange planktivorous "Mourasuchus" (a contemporary of "Purussaurus"), at 12 m, 11–12 m, 10.15 m, and 12 m, respectively.
Stylinodon
The skull suggests it had a blunt face, and a very short snout. Species ranged in size from pigs to leopards, reached a body mass of up to . Its canines had developed into huge, incisor-like root-less teeth. "Stylinodon"'s molars were covered in enamel and continued growing throughout its life. Most likely, it fed on rough roots and tubers.
Cephalopod size
Marine biologist Frederick Aldrich, who personally examined more than a dozen giant squid specimens, wrote that his largest specimen from Newfoundland bore tentacular suckers "approximately two inches [] in diameter" but that "[s]uckers and their toothed armament of over twelve inches [] in diameter have been found in the stomachs of sperm whale as indigestible wastes" (Aldrich, 1980:59). This led him to entertain the idea of giant squid over long, and even to suggest a binomial name for this super-sized species, were it ever to be discovered: "Architeuthis halpertius" (Aldrich, 1980:59).
Phyllodon
As a hypsilophodontid or other basal ornithopod, "Phyllodon" would have been a bipedal herbivore. Its size has not been estimated, but as most adult hypsilophodonts were long, this genus would probably have been of similar size. Its similarity to the North American "Drinker" and "Nanosaurus" is another piece of evidence linking Late Jurassic Portuguese dinosaur faunas with the contemporaneous Morrison Formation dinosaurs.
Smilodon
Whether "Smilodon" was sexually dimorphic has implications for its reproductive behavior. Based on their conclusions that "Smilodon fatalis" had no sexual dimorphism, Van Valkenburgh and Sacco suggested in 2002 that, if the cats were social, they would likely have lived in monogamous pairs (along with offspring) with no intense competition among males for females. Likewise, Meachen-Samuels and Binder (2010) concluded that aggression between males was less pronounced in "S. fatalis" than in the American lion. Christiansen and Harris (2012) found that, as "S. fatalis" did exhibit some sexual dimorphism, there would have been evolutionary selection for competition between males. The structure of the hyoid bones suggest that "Smilodon" communicated by roaring, like modern big cats. The ability to roar may have implications for the social life of "Smilodon".
Aublysodon
The first skeletal material referred to an original "Aublysodon" species was a partial skull unearthed in Jordan, Montana in 1966 and described by Ralph Molnar in 1977/1978. The skull, specimen LACM 28741 at forty-five centimetres the length of an average human arm, bore pointed teeth attached to a long narrow snout. First thought to be a juvenile "Tyrannosaurus", then interpreted as a large dromaeosaurid, this "Jordan theropod" was given the name "Aublysodon molnaris" by Gregory S. Paul in 1988; in 1990 the name was by Paul emended to "Aublysodon molnari", applying the correct genitive. It was made a separate genus "Stygivenator" by George Olshevsky in 1995, but was later, in 2004, reinterpreted to be a juvenile "Tyrannosaurus rex" by Thomas Carr and Tom Williamson. Another partial skeleton from New Mexico, specimen OMNH 10131, was in 1990 considered to represent "Aublysodon", but later research by Thomas Carr and Tom Williamson first referred it to "Daspletosaurus" and ultimately to "Bistahieversor". In 1988 Paul also created another species when renaming "Shanshanosaurus huoyanshanensis" Dong 1977 into "Aublysodon huoyanshanensis". It probably represents a "Tarbosaurus" specimen.
Xenoposeidon
Like other sauropods, "Xenoposeidon" would have been a large quadrupedal herbivore. It was relatively small for a sauropod. Extrapolating from the vertebra suggests that the type individual of "Xenoposeidon" could have been about 15 metres (50 ft) long and weighed approximately 7.6 tonnes (8.4 short tons), if it resembled "Brachiosaurus", to 20 m (65 ft) long and 2.8 tonnes (3.1 short tons), if it was built like the longer, lighter "Diplodocus".
Subhyracodon
Subhyracodon is an extinct genus of cow-sized rhinoceroses. With a length of 2.4 m (8 ft) and a weight estimated of 381.3 kg (in "S. mitis"), it was a tapir-sized herbivore on the plains of early Oligocene South Dakota 33 million years ago (White River Fauna), smaller than only the "Megacerops" and the chalicotheres. "Subhyracodon" had no horns, relying more on its speed to escape, but a species found at Wind Cave National Park had a pair of bony nasal ridges. The genus "Caenopus" and species originally referred to"Aceratherium" were synonymized into "Subhyracodon"
Smilodon
In his 1880 article about extinct cats, Cope also named a third species of "Smilodon", "S. gracilis". The species was based on a partial canine, which had been obtained in a cave near the Schuylkill River in Pennsylvania. Cope found the canine to be distinct from that of the other "Smilodon" species due to its smaller size and more compressed base. Its specific name refers to the species' lighter build. This species is known from fewer and less complete remains than the other members of the genus. "S. gracilis" has at times been considered part of genera such as "Megantereon" and "Ischyrosmilus". "S. populator", "S. fatalis" and "S. gracilis" are currently considered the only valid species of "Smilodon", and features used to define most of their junior synonyms have been dismissed as variation between individuals of the same species (intraspecific variation). One of the most famous of prehistoric mammals, "Smilodon" has often been featured in popular media and is the state fossil of California.
Microeledone
Microeledone mangoldi, the sickle-tooth pygmy octopus, is a species of octopus from the family Megaleledonidae. This species was described in 2004, the type specimen being a male which was collected from a depth of approximately near the Norfolk Ridge, in the southwest Pacific Ocean near New Caledonia. It is a very small octopus which has a single row of suckers, lacks an ink sac and has a radula with seven rows of teeth with the unique central tooth, called the rechidian tooth, being curved with a grooved tip. The remaining teeth are flat and plate like and so are also distinctive. The smooth creamy-pink body lacks any chromatophores. The specific name honours the Swiss malacologist and marine biologist Katharina Mangold-Wirz (1922-2003).
Pliosaurus
Using "Liopleurodon", another large pliosaurid, as a guide, a specimen found in the Svalbard islands of northern Europe has been estimated to have been long, in weight and had teeth long. It is estimated to have lived approximately 147 million years ago. Later on, thorough scrutiny of this Svalbard specimen revealed that it was not as massive as originally claimed; total length estimates have been revised to and was named "Pliosaurus funkei" in Knutsen et al. 2012, with estimated skull lengths of 160–200 cm and a forelimb length of 300 cm for the holotype (PMO 214.135), and an estimated skull length of 200–250 cm for the referred specimen (PMO 214.136), suggesting that the animal had proportionally bigger flippers than other pliosaurs compared to the skull size and dimensions of the vertebrae. This estimate has since been questioned due to the smaller size of "P. funkei" vertebrae in comparison to "Kronosaurus", which was used to obtain the estimate. Analysis of bones from the four flippers suggest that the animal cruised using just two fore-flippers, using the back pair for extra speed when pursuing and capturing prey. "P. funkei" brain was of a similar type and size, proportionally, to that of today's great white shark.
Cephalopod size
A subadult female found in the Ross Sea in March 2003 also had a mantle length of around , and measured in total length, but was comparatively light at only (Griggs, 2003; McClain "et al.", 2015). Another giant specimen, a female measuring in total length and weighing , was recovered intact in 2014 (Farquhar, 2014). Other notably large colossal squid specimens include an immature female taken by trawl off Dronning Maud Land in 1981 ( ML and TL; Ellis, 1998a:147), a specimen caught alive in South Georgian waters in 2005 (estimated TL and weight; [Anonymous], 2005b), and two specimens recovered from sperm whale stomachs between 1956 and 1957 off the South Shetland Islands and South Orkney Islands (reportedly around TL, respectively; Sweeney & Roper, 2001:56; see Korabelnikov, 1959:103 and Yukhov, 1974:62).
HMS Myrmidon (1813)
"Myrmidon" had a length at the gundeck of and at the keel. She had a beam of , a draught of and a depth of hold of . The ship's tonnage was 509 tons burthen. "Myrmidon" was armed with eighteen 32-pounder carronades and a pair of 9-pounder cannon as chase guns. The ship had a crew of 135 officers and ratings.
Crocodilia
Ancient historians have described crocodilians from the earliest historical records, though often their descriptions contain as much legend as fact. The Ancient Greek historian Herodotus (c. 440 BC) described the crocodile in detail, though much of his description is fanciful; he claimed that it would lie with its mouth open to permit a "trochilus" bird (possibly an Egyptian plover) to enter and remove any leeches it found. The crocodile was one of the beasts described in the late-13th century Rochester Bestiary, based on classical sources, including Pliny's "Historia naturalis" (c. 79 AD) and Isidore of Seville's "Etymologies". Isidore asserts that the crocodile is named for its saffron colour (Latin croceus, 'saffron'), and that it is often twenty cubits () long. He further claimed that the crocodile may be killed by fish with serrated crests sawing into its soft underbelly, and that the male and female take turns guarding the eggs.
1525 Savonlinna
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Savonlinna" measures between 11.73 and 12.23 kilometers in diameter and its surface has an albedo between 0.045 and 0.130. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.084 and a diameter of 12.06 kilometers based on an absolute magnitude of 12.9. It also classifies the body as a S-type asteroid, despite its derived albedo.
1675 Simonida
According to the space-based Japanese Akari satellite, "Simonida" measures 12.16 kilometers in diameter, and its surface has an albedo of 0.211. The "Collaborative Asteroid Lightcurve Link", however, agrees with the results obtained by 8 observations of the Infrared Astronomical Satellite IRAS, that gave a diameter of 11.08 kilometers and an albedo of 0.25 with an absolute magnitude of 11.9.
Eagle (Middle-earth)
The Lord of Eagles in the First Age, said in "The Silmarillion" to be the "mightiest of all birds that have ever been", with a wingspan of thirty fathoms (54.9 meters, or 180 feet) and a beak of gold. His name translates from Sindarin, an Elven language devised by Tolkien, as 'King of Eagles'; its cognate form in Quenya, another Elven language, is Sorontar. He led the eagles during most of their appearances in "The Silmarillion", and has a significant role of his own.
Machairodontinae
In 2004 an experiment used a pair of mechanical aluminum jaws, cast from the CT scans of a "Smilodon fatalis" from the La Brea tar pits, to simulate several biting techniques possibly used by "Smilodon", including the shearing bite, on a fresh domestic cow carcass. The belly of the cow was found to be too large in diameter for the canines to puncture the skin, which were instead deflected off the body, with the mandible blocking their access. However, the model pulled its jaw upward as modern cats bite, while machairodonts most likely did not, instead pressing their skulls down with the aid of their neck muscles. This flaw in the procedure might nullify the results and leave the belly-shearing hypothesis untouched.
Diagrams
6395 Hilliard
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Hilliard" measures 4.082 kilometers in diameter and its surface has a high albedo of 0.351, while the "Collaborative Asteroid Lightcurve Link" assumes a standard albedo for stony asteroids of 0.20 and calculates a large diameter of 4.71 kilometers with on an absolute magnitude of 14.0, as diameter and albedo (reflectivity) are inversely related to each other.
Micodon
"Micodon" is clearly within the size range of living marmosets but is well below the size range of larger marmosets, such as "Callimico goeldii" and "Leontopithecus chrysopygus". Since the callitrichines are probably a modified radiation that underwent their major diversification at a small body size, it is considered very likely that "Micodon" is a marmoset. The "Micodon" M1 suggests that body size/tooth size reduction preceded the loss of the hypocone cusp. It has been argued that the combination of tricuspid molars and small size literally define a marmoset phyletically. On the other hand, "Callimico" is a four-cusped ceboid whose anatomy suggests that it is cladistically closest to the tricuspid marmosets, and alternative schemes of platyrrhine phylogeny place the four-cusped cebines, "Cebus" and "Saimiri", as the sister-taxon of the entire group. The upshot of these latter views is that a four-cusped molar would be fully expectable in small, ancestral callitrichine, and even in callitrichin sister-group. The upper first molar (M1) with a subtriangular outline with a narrow lingual side resembles that of the oldest New World primate discovered to date, the Late Eocene "Perupithecus" from the Peruvian Amazon.
Squalodontidae
Squalodontidae or the shark-toothed dolphins is an extinct family of large toothed whales who had long narrow jaws. Squalodontids are known from all continents except Antarctica, from the Oligocene to the Neogene, but they had a maximal diversity and global distribution during the Late Oligocene and Early to Middle Miocene ().
Plestiodon gilberti
Plestiodon gilberti, commonly known as Gilbert's skink, is a species of heavy-bodied medium-sized lizard in the family Scincidae. The species is endemic to the southwestern United States, and grows to about in total length (including tail).
HSwMS Sölve
The "Hildur"-class monitors were designed by Lieutenant John Christian d'Ailly, from a proposal by John Ericsson, for the defense of Lake Mälaren and the Stockholm archipelago. "Sölve" was long overall and had a beam of . She had a draft of and displaced . Her crew numbered 48 officers and men. The ship had rudders at bow and stern.
Smilodon
Scientists debate whether "Smilodon" was social. One study of African predators found that social predators like lions and spotted hyenas respond more to the distress calls of prey than solitary species. Since "S. fatalis" fossils are common at the La Brea Tar Pits, and were likely attracted by the distress calls of stuck prey, this could mean that this species was social as well. One critical study claims that the study neglects other factors, such as body mass (heavier animals are more likely to get stuck than lighter ones), intelligence (some social animals, like the American lion, may have avoided the tar because they were better able to recognize the hazard), lack of visual and olfactory lures, the type of audio lure, and the length of the distress calls (the actual distress calls of the trapped prey animals would have lasted longer than the calls used in the study). The author of that study ponders what predators would have responded if the recordings were played in India, where the otherwise solitary tigers are known to aggregate around a single carcass. The authors of the original study responded that though effects of the calls in the tar pits and the playback experiments would not be identical, this would not be enough to overturn their conclusions. In addition, they stated that weight and intelligence would not likely affect the results as lighter carnivores are far more numerous than heavy herbivores and the social (and seemingly intelligent) dire wolf is also found in the pits.
Cifelliodon
The holotype of "Cifelliodon wahkarmoosuch" is an exceptionally well-preserved skull, housed at the Natural History Museum of Utah. 
The skull measures 70 mm in length, giving an estimated body mass of 0.91-1.27 kg. The skull is broad and shallow with a reduced tooth count. There is a prominent sagittal crest. Inside the skull on each side are two incisors, a canine, and four postcanines, all of them broken off at the gumline except for the last molars. These last molars had not yet erupted, and so their intact crowns allowed palaeontologists to identify this mammal.