Digging up Dinosaurs

Diplodocus

Discovered in 1877 during the  Bone Wars , the first Diplodocus specimens were incomplete. Spurred on by these initial discoveries, the Carnegie Museum of Natural History launched an expedition in 1899 that unearthed a well-preserved and nearly complete specimen which was named Diplodocus carnegii.

In combination with the discovery of other specimens, the Carnegie Museum of Natural History created a complete composite Diplodocus skeleton nicknamed  "Dippy" . This skeleton was subsequently cast in plaster and sent to museums worldwide, sparking an international public interest in dinosaurs.

Tyrannosaurus Rex

The Tyrannosaurus rex is arguably one of popular culture's most easily recognizable dinosaurs. These massive carnivores walked the earth over 66 million years ago during the Late Cretaceous period.

Although it wasn't the first specimen of the species discovered, “Sue” is one of the largest, most complete, and best-preserved ever found. Discovered in 1990 in western South Dakota, the skeleton is over 90% complete and holds the record for length (40.5). Today “Sue” can be found at the Field Museum of Natural History in Chicago.

The remarkable preservation and completeness of Sue’s skeleton make it a treasure trove for scientific discoveries. It represents a rare chance for paleontologists to examine the anatomy of a complete specimen.

While the specimen is nicknamed “Sue”, after Sue Hendrickson, who made the discovery, scientists don’t know the sex of this particular individual.

Archeopteryx

Archeopteryx lived during the Late Jurassic period (150 million years ago) in what is now southern Germany. The first complete specimen was discovered in 1861. With evidence of broad feathered wings, it was long thought to be a transitional fossil, demonstrating a link between dinosaurs and modern birds.

However, more recent discoveries have identified other more convincing feathered transitional fossils in other species, such as Sinosauropteryx. Modern technological advances have allowed us to closely examine dinosaurs' skin and feather remains in new and exciting ways, producing exciting discoveries related to their  colors and patterns .

Dinosaur Teeth

The biggest and most dramatic fossils don't always yield the most incredible prehistoric finds. Sometimes even the tiny partial fossils and their location, either within geologic layers or geographically, can significantly contribute to our understanding of dinosaurs.

In the case of these  baby dinosaur teeth found in Alaska’s North Slope , the fossils tell scientists much about dinosaur behavior. The presence of teeth from hatchling dinosaurs provides compelling evidence that dinosaurs nested and reared young above the Arctic Circle. Yet this doesn’t complete the puzzle. Learning how highly adaptable dinosaurs had to be to remain in this cooler environment year-round raises new questions about their biology.

Spinosaurus

This ancient ‘spine lizard’ roamed what is now North Africa during the Late Cretaceous period (99 to 93.5 million years ago). The very first specimen was discovered in Egypt in 1912 but was subsequently lost during the destruction of World War II. Additional species specimens have since been unearthed in the 21 ^st  century, contributing to our understanding of this species. However, there is only so much we can determine from fossils, and the purpose of the prominent sail along the back of Spinosaurus remains a question: Was it for display, thermal regulation, or something else entirely?

Relatives from the Spinosaurid family have been found across the world in various proportions and configurations, including Baryonyx, discovered in the United Kingdom, and the Oxalaia found in Brazil.

Afrovenator

Measuring approximately 8 metres (26 feet) long and known by a single, relatively complete skeleton discovered in 1993, the Afrovenator illustrates another diverse example of the theropod carnivores that roamed prehistoric northern Africa in the middle Jurassic.

Afrovenator belongs to the same Megalosaurid family as Megalosaurus. Establishing relationships between species and the geologic times in which they existed can help create a picture of how dinosaurs spread across the continents as they became geographically isolated during the break-up of Pangea.

Velociraptor

While the name conjures images from popular media, you’re likely imagining members from the related genus Deinonychus; the actual Velociraptor was roughly the size of a turkey. Paleontologists are fortunate in that there are over a dozen described fossil skeletons of Velociraptors contributing to our understanding of the species. However, the  “Fighting Dinosaurs”  specimen is an incredible example of rapid burial and captures the conflict between a Velociraptor and Protoceratops as if frozen in time. Thought to have been buried by a sandstorm or a collapsing sand dune in the middle of their battle, this rare fossilized moment reveals intimate details of predation and the interactions between species.

Oviraptor

The Oviraptor was first discovered in the fossil-rich formations of southern Mongolia in 1923. This species represents a case of mistaken identity and is a lesson in why it’s so important for scientists to excavate not only individual fossils but also their location and surroundings. This additional data is crucial in building a picture of the creatures' environment and behaviors.

In this case, the misnomer “egg thief” was assigned when the first specimen was found atop a nest of eggs presumed to be from another species. However, it wasn’t until other examples were later discovered, all found with clutches of eggs, that it was suggested that these dinosaurs were brooding their eggs as opposed to stealing those of another species.

Muttaburrasaurus

The herbivorous Muttaburrasaurus lived in what is now northeastern Australia during the early Cretaceous. The first specimen was unearthed in 1963 and resembled its North American and European relative, the Iguanodon. The fossils of Muttaburrasaurus are also some of the most complete specimens to be discovered on the continent.

Gigantosaurus

Tyrannosaurus wasn’t the only massive carnivore lumbering around the prehistoric world. Some impressive examples even came before. Discovered in 1993, Giganotosaurus was the “giant southern lizard” of the theropod dinosaurs and existed 95 million years ago in what is now Argentina (that’s approximately 37 million years before T. rex). Having similar incredible dimensions as Tyrannosaurus rex potentially enabled Giganotosaurus to prey upon the massive sauropods of the time in South America.

Patagotitan

The Patagotitan belongs to the sauropod group of Titanosaurs, whose members are examples of the largest land animals known to have ever existed. Long necks and tails, small heads, and four giant legs characterized these massive creatures.

What is now South America appears to be the land of the giants as it is especially bountiful with examples of gigantic individuals from this diverse group of sauropods. For instance, Patagotitan, discovered in 2014 and named after the Patagonia region of Argentina, where it was found, is currently perceived to be one of the largest Titanosaurs. Measuring 37 metres (121 feet long) and tipping the scales at an estimated 69 tonnes (76 tons), this lumbering land giant weighed more than 12 African elephants!

However, complete specimens are rarely found due to their size and vast proportions, making accurate size estimates difficult. Nevertheless, new research and discoveries are continuously emerging, shaping our understanding of these titans, and this record may soon be surpassed by  another giant from South America  that was unearthed in 2021.

Baryonyx

First discovered in 1983 in Surrey, England this Baryonyx “heavy claw” fossil is one of the most complete theropod skeletons found in the United Kingdom. The Baryonyx genus of dinosaurs belongs to the Spinosaurid family, which contains the larger relative Spinosaurus. These dinosaurs existed from the early to mid-Cretaceous and have been found all over the world.

Generally, they’re characterized by their robust arms, an enlarged claw on their first finger, and long narrow skulls which resemble those of modern crocodilians. These traits would have made them excellent hunters in their suggested semiaquatic habitats. Baryonyx, specifically, was the first theropod dinosaur to show fish-eating behavior, as fish scales were found in the stomach area of this fossil.

Ankylosaur

Perfect fossils are scarce, but sometimes conditions and circumstances align to create unique fossilized specimens. Just such exceptional conditions occurred to preserve this Borealopelta specimen. Discovered in 2017 by a shovel operator in a northern Alberta mine, this ankylosaur was washed out to prehistoric sea after death before settling on the seafloor and becoming encased in sediment. The durability of the creature's armored skin and the unique conditions of fossilization meant that incredible details were preserved in three dimensions, including the armoured plates, skin, and stomach contents. Thanks to the detail of the fossil specimen, it earned the nickname "sleeping dragon".

Remarkably preserved specimens such as this, which now resides at the  Royal Tyrell Museum in Alberta , represent significant scientific opportunities. For example, scientists could determine the creature's diet from this specimen and even  study pigmentation in the skin and scales .