2017 proved to be a whirlwind year for dinosaur lovers and paleontologists alike. The 10 fascinating new findings uncovered this year reshaped our view of these ancient giants, from tender T. rex courtship rituals to a revamped family tree that could overturn a century‑old classification.

10 Fascinating New Highlights of Dinosaur Science

10 T. Rex Was A Gentle Lover

A fresh investigation seeks to overturn the classic image of the terrifying Tyrannosaurus rex. Researchers from Carthage College in Wisconsin teamed up with scientists at Louisiana State University to portray T. rex as a surprisingly affectionate creature that engaged in delicate face‑rubbing as part of a pre‑copulatory play ritual.

Their hypothesis stems from a Montana discovery of a previously unknown tyrannosaur named Daspletosaurus horneri – literally “Horner’s frightful lizard.” This species, which roamed the Earth roughly 74 million years before the iconic T. rex, supplies crucial anatomical clues about the later giant.

Well‑preserved skulls of D. horneri, as well as other tyrannosaurs, reveal a mask of armor‑like scales covering the snout and jaws, pierced by countless tiny nerve openings called foramina. These foramina would have rendered the snout as sensitive to touch as a human fingertip.

Scientists argue that such a tactile muzzle would have been used to explore the environment and, during mating season, to gently rub snouts with a partner. The sensory network is supplied by the trigeminal nerve, a structure still important for touch in modern crocodiles and alligators.

9 A New Dinosaur Was So Weird That It Was Thought To Be A Hoax

When European naturalists first encountered the platypus in the late 1700s, many dismissed the bizarre creature as a hoax. A similar wave of disbelief greeted a 2017 discovery of a dinosaur that combined land‑and‑water habits in a single, odd package.

The new species, a close cousin of Velociraptor, lived about 75 million years ago and was christened Halszkaraptor escuilliei in honor of paleontologist Halszka Osmolska and fossil collector François Escuillie.

Its morphology was truly eccentric: about the size of a mallard, it sported razor‑sharp claws, a duck‑like snout, and a long swan‑shaped neck. While capable of sprinting on solid ground, its anatomy also bore hallmarks of amphibious life seen today in birds and reptiles.

Although its look and lifestyle set it apart, researchers are confident that Halszkaraptor escuilliei does not represent a direct bird ancestor but rather a distinct branch that will likely give rise to a new subfamily.

The fossil’s provenance added to the skepticism. Unearthed in Mongolia’s Ukhaa Tolgod region, the specimen vanished into the black‑market trade before eventually reaching Escuillie. To confirm its authenticity, scientists employed a synchrotron particle accelerator to scan the rock‑embedded remains, verifying that every bone belonged to a single animal.

8 Eater Turned Vegetarian During Adulthood

Numerous animals undergo dramatic shifts in form or habit as they mature, but no reptile—living or extinct—has been shown to swap its diet from carnivorous to herbivorous. In 2017, a team from Beijing’s Institute of Vertebrate Paleontology and Paleoanthropology unveiled exactly such a transformation in the dinosaur Limusaurus.

Limusaurus, a diminutive biped that roamed the planet roughly 160 million years ago, was born with a set of dozens of tiny, one‑centimetre teeth. As the juveniles grew, they began shedding these teeth, and by the time they reached full maturity, the entire dentition had vanished.

The researchers examined 19 specimens spanning six age brackets, documenting not only the loss of teeth but also a staggering 77 additional anatomical tweaks over the animal’s lifespan, including alterations to skull shape and proportions.

One of the most striking changes was the upper jawbone bending downward to form a beak‑like structure, perfectly suited for cropping plant material. Adult Limusaurus also ingested stones, akin to modern birds that use gastroliths to grind food in their gizzards.

Scientists propose that this ontogenetic diet shift allowed adults to avoid competing with younger individuals for the same prey, thereby reducing intraspecific competition for resources.

7 Dino Hips Bring End To Common Species

A staple of North American dinosaur collections—formerly identified as Troodon formosus—has been knocked off the roster. Fresh research shows that specimens lumped under this name actually belong to at least two distinct genera.

Troodon formosus was first described over a century and a half ago in Montana and later reported from locales stretching from Mexico to Alaska, making it the most frequently recovered troodontid. However, a team at the University of Alberta re‑examined the material and uncovered inconsistencies.

Graduate researcher Aaron van der Reest discovered an exceptionally preserved troodontid pelvis in Alberta’s Dinosaur Provincial Park that displayed striking differences from previously known specimens. Comparative analysis led to the dismissal of Troodon formosus as a valid taxon, resurrecting the name Stenonychosaurus inequalis and introducing a brand‑new species, Latenivenatrix mcmasterae.

This taxonomic reshuffle carries major implications: the two newly recognized species are currently based on only a handful of fossils from Alberta, but the widespread fossils once assigned to Troodon across North America may now be split among several new taxa, opening the door for further discoveries.

6 A New Species Is Hailed As ‘Biggest Dinosaur’

The coveted title of “largest dinosaur” continues to spark fierce debate, as size remains a perennial fascination for the public. Because complete skeletons are rare, each new discovery can shift the scale‑race. In 2015, Dreadnoughtus stirred the conversation, and in 2017 another heavyweight entered the arena.

Enter Patagotitan mayorum, a titanic sauropod unearthed in Argentina’s Patagonian region. Like its fellow titanosaurs, Patagotitan belonged to the long‑necked, massive herbivorous group that dominated the Jurassic and Cretaceous landscapes.

The Argentine find comprises fossils from six individual animals, dated to roughly 100 million years ago. Scientists estimate Patagotitan’s mass at about 69 metric tons, its length at 37 metres (≈ 122 feet), and its height at 6 metres (≈ 20 feet).

Although these numbers firmly place Patagotitan among the giants, its status as the ultimate record‑holder remains contested. Paleontologist Kristi Curry Rodgers notes that the bones exhibit signs of incomplete growth, hinting that even larger specimens may yet be discovered.

5 Some Dinosaurs Incubated Their Eggs Like Birds

Even after decades of intensive study, the reproductive habits of dinosaurs still hold many secrets. A 2017 collaboration between French and Chinese scientists shed fresh light on how certain theropods tended to their eggs, revealing that some species literally sat on their clutches like modern birds.

The focus of the study was the oviraptorosaurs—a feathered clade of maniraptoran dinosaurs famously dubbed the ‘chicken from hell.’ Early finds showed these creatures perched over nests, leading to the mistaken belief that they were egg‑thieves.

Subsequent analyses suggested that oviraptorosaurs were, in fact, caring parents incubating their own offspring. The new research bolsters this view by demonstrating that the dinosaurs employed a brooding strategy akin to avian incubation.

The Franco‑Chinese team pioneered a technique to infer the incubation temperature by measuring the oxygen‑isotope composition of 70‑million‑year‑old fossilized eggs that still contained embryonic material. Their results indicated a steady temperature range of 35–40 °C (95–104 °F), matching the thermal profile of contemporary bird nests.

Beyond the specific findings, the methodological breakthrough promises broader applications, allowing paleontologists to reconstruct nesting behaviours across diverse dinosaur groups. While massive sauropods likely relied on external heat sources to avoid crushing their eggs, smaller theropods could have comfortably perched atop them.

4 Dinosaur Extinction Was Very Improbable

The most legendary mass‑extinction event in Earth’s history unfolded 66 million years ago, ending the reign of the non‑avian dinosaurs and eradicating roughly three‑quarters of all plant and animal species.

While several competing theories exist, the prevailing consensus attributes the catastrophe to a colossal asteroid or comet that slammed into the Yucatán Peninsula, creating the Chicxulub crater. A 2017 study from Tohoku University in Japan proposes that the disaster’s global impact was far from inevitable.

The impact hurled massive quantities of soot into the atmosphere, igniting a cascade of climate upheavals that decimated ecosystems worldwide. Yet, the researchers calculated that only about 13 percent of Earth’s surface contains enough hydrocarbon deposits to generate the soot load necessary for a Cretaceous‑Paleogene‑scale extinction.

Had the projectile struck elsewhere, the resulting environmental fallout would have been markedly milder, potentially sparing many lineages. In such an alternate timeline, dinosaurs might have survived the event, and mammals may never have risen to dominance.

3 New Species Was Misidentified As Archaeopteryx

Since its inaugural discovery 150 years ago, Archaeopteryx has occupied a starring role as the quintessential transitional fossil, linking dinosaurs and birds. Only twelve specimens have ever been catalogued, yet a 2017 analysis argues that one of these historic fossils actually belongs to a completely distinct species.

The specimen in question, unearthed in the 1970s and housed at the Teylers Museum in Haarlem, the Netherlands, earned the moniker “Haarlem specimen.” Compared with other Archaeopteryx finds, it is relatively incomplete and suffers from poor preservation.

Nevertheless, a fresh re‑examination uncovered enough morphological differences to separate it from Archaeopteryx. Discrepancies in bone proportions and the presence of paired furrows on the phalanges more closely resemble anchiornithids such as Anchiornis and Eosinopteryx.

These traits, combined with its geographic outlier status—far beyond the Chinese Jurassic formations that host all other anchiornithids—led researchers to name the animal Ostromia crassipes. The authors suggest that its wide distribution may have been achieved through flight, potentially reshaping our understanding of early avian dispersal.

2 Teleocrater Changes The Early History Of Dinosaurs

Although the fossil now known as Teleocrater was first uncovered in 1933, it remained a mystery until 2017 when paleontologist Sterling Nesbitt finally described it in a peer‑reviewed journal. The specimen had long been under the stewardship of British researcher Alan Charig, who mentioned the name Teleocrater rhadinus in his 1956 doctoral dissertation but never published formal findings.

Charig’s tight‑lipped approach—allowing only a select few to examine the bones—sparked speculation that even he was uncertain about the animal’s true identity. In 2015, Nesbitt’s team recovered three additional Teleocrater specimens, paving the way for a comprehensive description two years later.

Morphologically, Teleocrater looks nothing out of the ordinary: a two‑metre‑long carnivore with sharp teeth, bearing a striking resemblance to a modern monitor lizard. Yet, its significance lies in the clues it offers about the early diversification of archosaurs.

At the dawn of the Triassic, archosaurs split into two major branches—Pseudosuchia (the crocodile line) and Avemetatarsalia (the bird line). The fossil record from this pivotal interval is notoriously sparse, leaving many evolutionary questions unanswered.

Teleocrater is firmly placed within the avemetatarsalian lineage, suggesting it lived shortly after the split. Though not a direct dinosaur ancestor, it represents the oldest known cousin of dinosaurs, bridging a crucial gap in our knowledge.

What makes Teleocrater especially intriguing is its blend of crocodilian‑like traits, contrasting with earlier avemetatarsalians such as Lagerpeton, which were small, bipedal runners. This mosaic of features indicates that bird‑like characteristics evolved gradually over a far longer timespan than previously believed, and ongoing study of Teleocrater promises to further rewrite the early chapters of dinosaur evolution.

1 New Model Aims To Completely Rewrite The Dinosaur Family Tree

While Teleocrater’s revelations already challenge conventional views of early dinosaur evolution, a bold new framework from the University of Cambridge seeks to overturn the very foundation of dinosaur classification. The proposal aims to replace the long‑standing division into Ornithischia and Saurischia, a scheme first introduced by Harry Seeley over a century ago.

The Cambridge team harnessed computer simulations to evaluate 450 anatomical characters across 75 dinosaur taxa, grouping species based on shared traits rather than solely on hip morphology. This exhaustive analysis generated tens of thousands of potential phylogenies, from which the 80 most plausible scenarios were merged into a consensus tree.

The resulting model not only repositions many groups that were once thought to be close relatives onto entirely separate branches, but also pushes back the earliest appearance of dinosaurs by roughly ten million years and into the northern hemisphere. As a consequence, the new tree has sparked vigorous debate within the paleontological community, and its ultimate acceptance remains to be seen.

We all know T. rex as a huge, ferocious monster, but when you line up the 10 lesser known dinosaurs that prowled the ancient world, the famed tyrant lizard suddenly looks more like a cuddly puppy than a true apex predator.

10 Lesser Known Dinosaurs That Pack a Scary Punch

10 Sinornithosaurus

Sinornithosaurus was a diminutive, feather‑covered dromaeosaur that shared a close kinship with Velociraptor. Its body was sleek and elongated, sporting a crocodile‑like snout and a mischievous, tooth‑filled grin that made it look like a tiny, flamboyant lizard draped in vivid plumage.

While some scientists suspect it may have hunted in coordinated packs—much like its raptor relatives—the fossil record offers only scant proof. What truly sets Sinornithosaurus apart is the emerging consensus that it possessed a venomous bite, a trait unseen in other dinosaurs.

The exact composition of its venom remains a mystery, but the mere notion of a feathered, night‑stalking predator that could inject a toxic dose in a single snap sends shivers down anyone’s spine.

9 Therizinosaurus

Therizinosaurus was a colossal beast weighing roughly 100 kg (220 lb) that roamed ancient Mongolia. Its most striking features were its absurdly long, needle‑like claws and a giraffe‑sized neck, giving it an almost prehistoric giraffe‑like silhouette.

Although those gigantic claws could easily rival Freddy Krueger’s in terror factor, researchers believe the animal primarily used them to harvest vegetation. Yet, the scientific community remains divided over whether it was a strict herbivore or an opportunistic omnivore that occasionally sampled meat.

This dietary ambiguity only adds to its menace; imagine a towering creature that could swing those claws at you for a snack or simply regard you as a bothersome plant‑eater.

8 Ceratosaurus

Ceratosaurus was a mid‑sized theropod roaming the Jurassic landscapes of present‑day North America and Europe. Its bulk featured short, stubby arms and a prominent horn jutting from its skull, giving it a distinctive profile.

At first glance it might appear as a generic cousin of T. rex, but don’t be fooled. Its secret weapon was an extra digit—four fingers on each hand instead of the usual three—granting it a subtle yet decisive advantage over rival predators.

This seemingly minor tweak helped Ceratosaurus dominate the Late Jurassic food chain for over 11 million years, a feat that underscores why it deserves more spotlight than many of its flashier contemporaries.

7 Carnotaurus

Carnotaurus prowled the Late Cretaceous of South America, boasting a heavily built frame adorned with formidable spikes and bony protrusions. Its most eye‑catching feature was a pair of demonic horns that cast ominous shadows over its reptilian eyes.

Those horns gave the creature its name—Latin for “meat‑eating bull.” While its forelimbs were diminutive enough to make a T. rex look chuckling, recent studies suggest those tiny arms didn’t hinder its speed; in fact, Carnotaurus may have been swifter than the famed tyrant.

So despite its stubby arms, this horned predator combined raw power with surprising agility, making it a terrifying contender in its ancient ecosystems.

6 Utahraptor

Utahraptor was an Early Cretaceous dromaeosaur that called what is now Utah home. Its sleek, feather‑covered form resembled a supersized version of the classic Velociraptor, complete with a long, balancing tail and powerful forearms.

At a staggering 7 meters (23 ft) in length and wielding 23‑centimeter (9‑inch) clawed talons, it tipped the scales at about 900 kg (2,000 lb)—a true heavyweight among raptors.

Beyond its sheer size, Utahraptor holds the unique honor of being Utah’s official state dinosaur, a legal badge that underscores its iconic status and reinforces its reputation as a formidable, claw‑wielding predator.

5 Pachycephalosaurus

Pachycephalosaurus was an herbivorous, bipedal dinosaur belonging to the Ornithischia order, sharing its era with the likes of T. rex and Triceratops. Its physique was robust, featuring thick legs, a stout tail, and a powerful neck.

The hallmark of this creature was its massive, dome‑shaped skull, a bone‑encrusted dome up to 30 times thicker than a human cranium. Scientists believe it served as a weapon, either for head‑butting rivals or defending against predators.

Intriguingly, recent hypotheses suggest Pachycephalosaurus might not have been a pure plant‑eater after all; it could have turned that dome into a carnivorous tool, ramming foes and then devouring them, turning the gentle‑looking dinosaur into a surprising predator.

4 Troodon

Troodon was a bipedal theropod from the Cretaceous, measuring about 3 meters (11 ft) from snout to tail tip. Its slender, torpedo‑shaped body housed razor‑sharp teeth and oversized eyes that hinted at keen nocturnal vision.

Although its arms weren’t exceptionally long, Troodon boasted the highest tooth count of any known theropod. Coupled with an estimated top speed of 64 km/h (40 mph), it could sprint almost as fast as a racehorse.

The most astonishing attribute, however, was its brain size. Researchers argue that Troodon was the smartest dinosaur, suggesting a level of intelligence that would make it a cunning, strategic hunter rather than a mindless beast.

3 Giganotosaurus

Giganotosaurus roamed Late Cretaceous South America, sporting a bulky build with thick limbs, a massive torso, and a sturdy neck. Its silhouette resembled the classic giant theropods of its era.

Don’t let its familiar shape fool you—this predator was slightly larger than T. rex and is believed to have been the sole hunter capable of taking down the gigantic sauropod Argentinosaurus, the largest land animal ever recorded.

Adding to its fearsome résumé, Giganotosaurus could sprint up to 50 km/h (31 mph), outpacing even the fastest recorded human, cementing its place atop the Late Cretaceous food chain.

2 Allosaurus

Arguably the most recognizable dinosaur on this roster, Allosaurus lived during the Jurassic in what is now the United States. Its design was surprisingly sleek for a creature of its size, featuring a thin neck and moderately thick legs.

Unlike many Jurassic theropods, Allosaurus was built for speed, clocking a top running pace of 21 km/h (13 mph), allowing it to chase down prey with relative ease.

Measuring between 8 and 11 meters (25‑35 ft) from snout to tail tip, its name translates to “different lizard,” a nod to the paleontologist who thought its unique appearance warranted a distinctive moniker.

1 Spinosaurus

Spinosaurus prowled the Cretaceous seas of North Africa, boasting a sleek, torpedo‑shaped body, a thin neck, and powerful limbs. It holds the title of the largest predatory dinosaur ever, out-sizing both T. rex and Giganotosaurus.

The creature’s most striking feature was a towering sail that ran along its back. While the exact purpose remains debated, the leading hypothesis suggests it served as a display structure—much like a peacock’s tail—to attract mates.

Adding to its legend, Spinosaurus is the only known dinosaur that actively engaged with the massive crocodylian Sarcosuchus, a 12‑meter (40‑ft), 10‑ton predator, proving its dominance in both land and water realms.

Welcome to a whirlwind tour of 10 fascinating peeks into the ordinary—but astonishing—habits of the creatures that ruled Earth for nearly 200 million years. While movies give us roaring battles and epic chases, paleontologists have unearthed a treasure trove of subtle clues that reveal how these reptiles ate, slept, swam, and even flirted. Grab your explorer’s hat; the Mesozoic era is about to get a lot more personal.

10 Fascinating Peeks Into Their Secret Lives

1 They Suffered From Parasites And Ulcers

Fossilized droppings, known as coprolites, act like ancient medical records. By examining these stinky time‑capsules, scientists discovered that dinosaurs were not immune to the same microscopic annoyances that plague modern pets. In a Belgian graveyard of Iguanodon remains, researchers found coprolites teeming with cyst‑forming Entamoeba organisms, along with trematode and nematode worm eggs—parasites that have barely changed in the 125 million years since they first invaded their hosts.

Even the fearsome Tyrannosaurus rex wasn’t spared. Paleopathologists have identified tiny perforations in fossilized tyrannosaur jaws that appear to be the work of protozoan parasites, the kind that cause ulcerations and lesions in the mouth and throat of contemporary animals. In short, the top predator of the Cretaceous dealt with the same microscopic nuisances that bother your house cat.

2 Some Land Dinosaurs Swam After Prey

When you think of theropods, you probably picture them sprinting across dry plains, snapping at unsuspecting herbivores. Yet a set of claw marks preserved on a riverbed in Sichuan Province tells a different story. A three‑toed predator—smaller than a classic T. rex but still formidable—was caught on film (well, stone) as it chased a quarry that leapt into the water, swimming about 15 metres (roughly 50 ft) while leaving a series of perfectly spaced, three‑finger impressions.

The marks show a meticulous left‑right, left‑right pattern, indicating a coordinated swimming stroke rather than a frantic splash. This evidence suggests that at least some theropods were comfortable in aquatic environments, perhaps using swimming as a natural hunting technique—much like modern dogs love to fetch in a pond.

3 Nonflying Birdlike Dinosaurs Ate Flying Birdlike Birds

Two exceptionally preserved specimens of Sinocalliopteryx have gifted scientists a rare glimpse into the predator’s last meals. This feather‑covered, 2.4‑metre (8‑ft) long theropod, a distant cousin of the infamous “Compy,” was not built for flight, but it certainly enjoyed a menu of airborne prey.

One fossil revealed the remains of a tiny, feathered flyer named Sinornithosaurus, a creature capable of short‑range gliding. The other specimen contained two small, crow‑sized birds of the genus Confuciusornis. While some argue these meals could be scavenged, the comparable stages of digestion suggest active predation, painting Sinocalliopteryx as a skilled hunter of early birds during the mid‑Cretaceous.

4 Sauropods Had Special Claws For Digging Nests

The massive, long‑necked sauropods sported a unique arrangement of foot claws that set them apart from virtually every other animal. When the foot was flexed, the claws aligned in a front‑to‑back scraper formation rather than forming a gripping hook.

Researchers interpreting these tracks argue that the claws weren’t meant for traction but for excavating shallow, trench‑like nests where the giants could deposit and protect their eggs. Further analysis of footprints from Morocco showed occasional sideways or even backward‑facing impressions, hinting that the dinosaurs could rotate their forefeet for agility, perhaps even “dancing” as they moved across varying terrains.

5 Hadrosaurs Communicated Via Built‑In Megaphones

Duck‑billed hadrosaurs, the ornithischian “duck‑bills,” weren’t just herbivorous grazers; many sported elaborate crests that functioned as natural resonating chambers. These hollow, tube‑filled structures amplified vocalizations, allowing the animals to broadcast calls across vast distances.

Such amplified sounds likely served multiple purposes: coordinating massive herds, warning off predators, and even courting potential mates. Some species, like Edmontosaurus regalis, displayed a comb‑like protuberance on the head—reminiscent of a rooster’s comb—that, while silent, may have acted as a visual indicator of reproductive health or species identity.

6 Some Made A Career Out Of Egg Snatching

Oviraptorosaurs, the beaked, feather‑covered dinosaurs often dubbed “egg thieves,” include the charmingly named Gobiraptor minutus. Roaming the lush wetlands of what is now Mongolia around 70 million years ago, this small theropod carved out a niche that didn’t rely on brute‑force carnivory.

Equipped with a robust beak and powerful jaws, G. minutus exploited a varied diet of tiny, crunchy snacks—mollusks, seeds, and, of course, eggs. Rather than tearing flesh, it specialized in snatching and cracking open eggs, making it an opportunistic omnivore that thrived in a landscape teeming with rivers and abundant life.

7 Triceratops Horns Weren’t (Primarily) For Fighting

The iconic three‑horned ceratopsian, Triceratops, may look like a walking tank, but recent research suggests its impressive horns and frill weren’t chiefly weapons. Instead, they functioned as visual signals of sexual fitness and species identity, much like a peacock’s extravagant tail.

While the armor could offer some defensive benefit, the primary evolutionary driver appears to be mate attraction. The flamboyant frills and sharp horns instantly broadcast a male’s genetic health to potential partners, reducing the need for costly physical confrontations.

8 Dinosaurs Engaged In Birdlike Foreplay

Evidence of dinosaur romance is scarce, but a series of shallow, bathtub‑sized ruts etched into a 100‑million‑year‑old limestone slab in Colorado offers a tantalizing clue. The paired grooves, each about 1.8 metres (6 ft) wide and ending in a distinct claw mark, resemble the courtship “scrape” marks left by modern birds.

Scientists propose that male dinosaurs performed pseudo‑nest‑building displays, scratching the ground to demonstrate their future nesting prowess and attract females. If true, these tracks represent the first tangible hint of dinosaurian foreplay, showing that love and courtship were as ancient as the creatures themselves.

9 Some Dinosaurs Were Night Owls

Many extinct reptiles possessed a bony ring around the eye—the sclerotic ring—that offers clues about their daily activity patterns. Species active during daylight exhibit smaller rings and pupils, while nocturnal animals have larger rings and wider central apertures to gather more light.

Analyses of sclerotic rings from massive, long‑necked herbivores suggest they were cathemeral—active both day and night—perhaps foraging during cooler twilight hours. Meanwhile, predatory theropods likely relied on their enhanced night vision to stalk prey under the cover of darkness, adding an extra layer of terror to the Mesozoic night.

10 T. rex Was Surprisingly Stealthy

Despite its massive size and reputation for thunderous footfalls, the tyrannosaur may have been a master of silent ambush. By feeding footprint data into computer models, researchers discovered that the T. rex’s foot was unusually elongated—twice as long as it was wide—creating a shape ideal for “seismic wave camouflage.”

This geometry meant that the vibrations generated by each step remained constant, making it difficult for prey to gauge the predator’s distance. In effect, a T. rex could creep up on unsuspecting herbivores without alerting them, turning the apex predator into a prehistoric ninja.

11 Young Dinosaurs Lived Unsupervised

Juvenile sauropods, the colossal long‑necked giants of the Jurassic and Cretaceous, led surprisingly independent lives. A young Diplodocus specimen, nicknamed Andrew, reveals that hatchlings possessed a narrower snout lined with spatula‑shaped teeth, unlike the broader, peg‑like teeth of adults.

This dental arrangement allowed youngsters to chew tougher vegetation that adult sauropods avoided, effectively reducing competition for food. Moreover, evidence suggests these juveniles roamed in age‑segregated foraging groups, staying clear of the massive adult herds to avoid being trampled and to exploit niche plant resources.

12 Some Dinosaurs Were Adorably Tiny

While the word “raptor” conjures images of fearsome predators, a recent discovery in South Korea turned that notion on its head. Fossilized footprints, only a centimeter (0.4 in) long and dating back roughly 110 million years, belong to a sparrow‑sized theropod now dubbed Dromaeosauriformipes rarus.

The minute tracks show a classic dromaeosaur gait: one claw lifted while the other two maintained contact, confirming its raptorial lineage. If the specimen represents a distinct species rather than a juvenile of a larger form, it would be the smallest dinosaur ever documented, proving that the dinosaur world housed creatures as tiny as a modern backyard bird.

When it comes to the ancient giants that once ruled the Earth, we often picture massive claws, thunderous footsteps, and spectacular extinction events. Yet, just like modern creatures, dinosaurs weren’t immune to the everyday woes of biology. In this roundup of the 10 diseases affected dinosaurs, we dive into the fossil record to reveal the surprising illnesses that plagued these prehistoric marvels—from flaky feathers to bone‑rotting infections.

10 Diseases Affected: A Prehistoric Health Overview

10 Dandruff

A 125‑million‑year‑old microraptor, roughly the size of a modern crow, holds the distinction of being the oldest known creature to sport dandruff. Researchers also uncovered dandruff‑like evidence in two larger relatives, the beipiaosaurus and the sinornithosaurus, each about twice the microraptor’s size.

The discovery was serendipitous: scientists studying how dinosaurs shed feathers noticed tiny corneocyte fragments embedded in the fossilized plumage. Corneocytes are the same cellular debris that flake off human skin during a bout of dandruff, making the find a remarkable cross‑species parallel.

Because corneocytes were traditionally thought to form only on skin, the researchers hesitated to label the finding outright as dandruff. Nevertheless, the evidence suggests that these ancient reptiles shed their feathers in fine, bird‑like packets rather than the massive clumps one might expect from an animal of their stature.

9 Cancer

Dinosaurs weren’t exempt from malignancies either. A pioneering study led by Bruce Rothschild of the Northeastern Ohio Universities College of Medicine scanned roughly 10,000 dinosaur fossils stored across North America, hunting for tell‑tale signs of tumors.

Out of the 97 hadrosaur specimens examined, 29 displayed unmistakable cancerous growths. The researchers differentiated these from benign tumors by comparing the fossilized lesions to modern human cancers, confirming a genuine malignant character.

While the exact cause remains speculative, the team hypothesizes that the conifer‑rich diet of hadrosaurs—full of needle‑like leaves containing carcinogenic compounds—might have contributed to the high incidence of bone cancer in these herbivores.

8 Malaria

Malaria’s ancient lineage stretches back to the age of dinosaurs, and some scientists argue it may have been a silent killer among them. Entomologist George Poinar Jr. from Oregon State University suggests that a now‑extinct species of midge, a tiny riverine insect, acted as a vector for a prehistoric malaria parasite.

Beyond midges, the research team suspects that sand flies and horseflies could also have transmitted the disease. These insects would have taken blood meals from dinosaurs, much as modern Anopheles mosquitoes feed on humans, spreading the parasite Paleohaemoproteus burmacis in the process.

Although the infection would have certainly made its hosts feel ill, Poinar cautions that malaria alone likely didn’t drive the mass extinction of the dinosaurs.

Nevertheless, the existence of a dinosaur‑specific malaria strain underscores how ancient ecosystems were already teeming with complex host‑parasite relationships.

7 Cataracts

Hard evidence for cataracts in dinosaurs is elusive, but the theory was popularized by ophthalmologist L.R. Croft in his book The Last Dinosaurs. Croft argued that rising global temperatures and intensified ultraviolet radiation during the late Cretaceous could have triggered widespread cataract formation among dinosaurs.

According to his hypothesis, the UV‑induced clouding of eyes would have caused progressive blindness, rendering countless dinosaurs unable to forage or evade predators. In contrast, mammals and surviving reptiles supposedly adapted by becoming nocturnal, thereby dodging the harmful sunlight.

Critics point out that natural selection would likely have favored protective mechanisms—such as reflective eye structures or behavioral shifts—making a mass cataract‑driven extinction seem improbable. Nonetheless, Croft’s speculation offers a vivid illustration of how environmental stressors could impact sensory health.

While the cataract theory remains controversial, it highlights the broader question of how climate‑driven changes might have influenced dinosaur physiology.

6 Osteoarthritis

Osteoarthritis, the most common form of arthritis in modern humans, also left its mark on the Mesozoic. Researchers examining the ankle bones of the small, feathered dinosaur Caudipteryx—about the size of a modern peacock—found evidence of joint cartilage wear in three of ten specimens.

This discovery makes Caudipteryx the oldest known creature to have suffered from osteoarthritis, dating back roughly 130 million years. The condition arises when the smooth cartilage covering bone ends deteriorates, causing the bones to grind directly against each other, leading to pain and reduced mobility.

While the exact cause for this particular dinosaur remains uncertain, the finding mirrors patterns seen in contemporary small birds, many of which also develop osteoarthritis as they age.

5 Osteomyelitis

In 1997, paleontologists unearthed the rib cage of a massive Lufengosaurus huenei, a sauropodomorph that roamed the Earth between 170 and 200 million years ago. The initial examination noted missing rib fragments, hinting at severe injuries, but the exact cause was left unresolved.

Two decades later, a fresh team revisited the fossil and concluded that the rib damage stemmed from a predatory attack by a larger carnivore. Though the predator’s identity remains unknown, its size must have rivaled the six‑meter, two‑ton stature of the Lufengosaurus.

Escaping the attack, the dinosaur suffered a grievous rib wound that soon became infected. Bacterial invasion led to pus‑filled cavities within the bone—a classic presentation of osteomyelitis, a devastating bone infection.

In modern medicine, osteomyelitis is most commonly caused by Staphylococcus aureus. While the ancient pathogen was not definitively identified, the disease would have produced fever, fatigue, and nausea, potentially hastening the animal’s demise.

Intriguingly, the infection could have arisen even without a bite; bacteria might have entered the bloodstream through another injury, eventually colonizing the rib bones.

4 Septic Arthritis

The duck‑billed hadrosaur, already known for its cancer‑laden bones, also bears evidence of septic arthritis—an inflammatory joint disease triggered when pathogens travel via the bloodstream to settle in joint spaces.

Unlike osteoarthritis, which stems from wear‑and‑tear, septic arthritis results from bacterial infection, often following a wound or direct inoculation. The condition can cause excruciating pain and immobilize the affected limb.

Researchers identified three abnormal growths on a hadrosaur elbow fossil, interpreting them as the aftermath of septic arthritis. While the exact infection route remains a mystery, the disease likely hampered the dinosaur’s ability to move, adding another layer of hardship to its life.

3 Intestinal Worms

Parasitic worms weren’t strangers to the dinosaur world. Fossilized coprolites—essentially dinosaur poop—have revealed remnants of tapeworms, trematodes, and even protozoan cysts, indicating a hidden ecosystem of internal pests.

Scientists estimate that some of these parasites could have stretched up to 30 meters (about 100 feet) in length, a modest size when compared to the massive hosts they inhabited. In modern humans, tapeworms can exceed 24 meters (80 feet), underscoring the sheer scale of these ancient parasites.

Because soft tissue rarely fossilizes, direct evidence of worms inside dinosaur bodies is scarce. Instead, researchers examine coprolites for eggs or cysts, a method that led George Poinar and Arthur Boucot in 2006 to identify trematode and nematode remains, along with a protozoan likely belonging to the genus Entamoeba, within a Belgian carnivorous dinosaur’s fossilized droppings.

2 Tooth Decay

The modestly sized Labidosaurus hamatus, a one‑meter‑long omnivorous reptile that lived alongside the dinosaurs, holds the dubious honor of being the earliest known creature to suffer from severe tooth decay.

Robert Reisz and his team at the University of Toronto Mississauga scanned the lower jaw of a fossilized specimen, uncovering extensive decay that had caused the loss of numerous teeth. The animal’s primarily herbivorous diet meant constant chewing, which gradually wore down enamel and exposed the sensitive dentine underneath.

Once the protective enamel eroded, bacteria invaded the exposed nerves, leading to painful abscesses and progressive decay. The resulting toothache would have hampered the creature’s ability to process food, illustrating how even modest reptiles faced dental challenges similar to modern animals.

1 Tuberculosis And Pneumonia

Pneumonia and tuberculosis predate the age of dinosaurs, with the earliest evidence found in the marine reptile Proneusticosasiacus, which lived over 245 million years ago. X‑ray analysis of its fossilized ribs revealed lesions that, after careful exclusion of other possibilities such as injury, cancer, fungi, and scurvy, were identified as pneumonia and Pott’s disease—a form of skeletal tuberculosis.

These infections persisted for months, perhaps years, before the animal finally succumbed. Some researchers argue that the specimen actually belongs to a closely related Cymatosaurus, but both belong to the nothosaur lineage, a group that split its time between land and sea much like modern seals.

Modern seals are among the few marine mammals known to contract tuberculosis, suggesting a possible ecological parallel. The discovery underscores that lung diseases have been a persistent threat throughout vertebrate evolution, affecting even the most ancient of reptiles.

When you think of the Mesozoic era, massive dinosaurs probably dominate the mental picture, but the world was also home to a parade of 10 weird critters that coexisted with these giants. From odd armored reptiles to early mammal experiments, each of these ten creatures adds a quirky chapter to pre‑history.

Why These 10 Weird Critters Matter

These unusual animals help scientists piece together evolutionary puzzles and remind us that the age of dinosaurs was a bustling ecosystem full of surprises.

10 Of Turtle

Sinosaurosphargis yunguiensis prowled what is now southwestern China about 243 million years ago. Its body sported a broad, turtle‑like ribcage, yet its “shell” wasn’t the solid carapace we picture today; instead it was a mosaic of tiny osteoderms—tiny, bony plates embedded in the skin.

Despite the turtle‑shaped silhouette, this creature wasn’t a true turtle. It branched off from the turtle lineage millions of years before the first genuine turtles appeared, sharing only a distant common ancestor.

The presence of those miniature bony shields throws a wrench into the classic story of turtle shell evolution, because the earliest true turtles seem to have lacked such a patchwork armor entirely.

9 Quite-First Mammal

Scurrying across the dry plains of Late‑Triassic France roughly 200 million years ago, the diminutive Megazostrodon resembled a strange, tiny shrew‑like creature. Though minuscule, it carries massive weight in the study of mammalian origins.

Scientists view it as a transitional form linking the mammal‑like cynodonts to bona‑fide mammals, making it a cornerstone for understanding how true mammals emerged. Yet its exact slot on the mammalian family tree remains a hotly debated topic.

While paleontologists argue over its classification, Megazostrodon was probably far too busy snapping up insects to worry about its place in evolutionary history.

8 The Tuatara

Okay, I’m technically bending the rules here. I’m not spotlighting the modern tuatara (*Sphenodon punctatus*) itself, but the entire Order Sphenodontia, a lineage that flourished in the early Jurassic, just under 200 million years ago.

These ancient relatives, known as rhynchocephalians, were once a diverse group of reptilian oddballs, sister to the squamates (today’s lizards and snakes). They looked like lizards but were distinct enough to earn their own order.Sadly, all rhynchocephalians vanished except for a single surviving genus—*Sphenodon*. The lone modern tuatara now clings onto existence, threatened by human activity, while its once‑vibrant cousins are long extinct.

7 The Fish Lizard

Ichthyosaurs, literally “fish lizards,” were a wildly diverse clan of marine reptiles that first appeared about 250 million years ago. Among them, the dolphin‑shaped Stenopterygius swam the seas around 180 million years ago.

A remarkably preserved fossil of Stenopterygius revealed not only faint skin pigments but also a thin layer of blubber beneath the skin. Though scientists can’t definitively label it warm‑blooded, the evidence hints at some degree of internal temperature regulation.

This adaptation would have given the creature an edge in the chilly depths, suggesting it could maintain a higher body temperature than typical cold‑blooded reptiles.

Ichthyosaurs once ruled the Mesozoic oceans as apex predators, only to disappear about 90 million years ago—roughly 25 million years before the non‑avian dinosaurs met their end.

6 The Beaver‑Otter

Castorocauda lutrasimilis showcases nature’s penchant for recycling successful designs. Its body resembled a modern beaver, complete with a flattened, scaly tail and webbed feet, yet its lifestyle was far from rodent‑like.

Equipped with a narrow skull bristling with needle‑sharp teeth, this Jurassic critter was adept at catching fish, much like today’s otters. Its fur, preserved in fossil form, mirrors that of modern aquatic mammals, featuring guard hairs over a dense undercoat.

Unlike most contemporary mammals, Castorocauda likely laid eggs, prompting comparisons to the platypus. Its blend of beaver, otter, and monotreme traits makes it a fascinating evolutionary mosaic.

5 The Long Lizard

The evolution of snakes—and the loss of their limbs—has sparked fierce debate among paleontologists. The discovery of a four‑limbed reptile, initially thought to be a snake, sent excitement through the community.

Identified as *Tetrapodophis amplectus*, this Early Cretaceous (~120 million‑year‑old) animal turned out to be a long‑bodied lizard, not a snake. Its tiny limbs, however, resemble those of early snake ancestors, supporting the idea that snakes may have shed limbs to become efficient burrowers.

Although *Tetrapodophis* didn’t rewrite snake ancestry, it reinforced the hypothesis that limb reduction was a key step toward the limbless condition seen in modern snakes.

4 Ancient Platypus

Monotremes—egg‑laying mammals like the platypus—trace back to an ancient lineage whose exact origins are still fuzzy. Estimates place their split from other mammals anywhere from the Early Triassic to the Jurassic.The earliest known platypus relative, *Teinolophos trusleri*, lived in the Early Cretaceous, about 120 million years ago. Though fossil material is often fragmentary, researchers believe that many of the odd traits seen in today’s platypus first emerged in these early forms.

While only one platypus species survives today, the group was once diverse, even reaching South America with *Monotrematum sudamericanum*. Fun fact: the echidna, another monotreme, branched off from a platypus‑like ancestor somewhere between 20 and 50 million years ago.

3 The Antarctic Sea Dragon

Featured in the BBC series *Prehistoric Planet*, the massive mosasaur *Kaikaifilu hervei* ruled the icy Late Cretaceous seas of Antarctica about 66 million years ago.

Belonging to the tylosaurine subgroup of mosasaurs, *Kaikaifilu* sported a sleek, serpentine body that set it apart from its bulkier cousins. At an estimated 33 feet (10 meters) long, it was the largest known predator from the South Pole.

Despite its dominance, the entire mosasaur line vanished at the end of the Cretaceous, marking a dramatic end to these marine titans.

2 The “Crazy Beast”

*Adalatherium hui*, unearthed in Madagascar and dating to just after the Cretaceous‑Paleogene extinction (~66 million years ago), earned its nickname for shattering conventional mammalian anatomy.

Lead researcher David Krause summed it up: “Knowing what we know about the skeletal anatomy of all living and extinct mammals, it is difficult to imagine that a mammal‑like *Adalatherium* could have evolved; it bends and even breaks a lot of rules.”

This bizarre creature boasted an unprecedented number of skull openings, peculiar teeth, and more vertebrae than any contemporary mammal. Its front half didn’t match its rear, leaving scientists puzzled over how it moved. At roughly seven pounds (3 kg), it may have been a juvenile, adding another layer of mystery.

1 Primates

Alright, I’ll admit another cheat. *Purgatorius janisae*—one of the earliest primate‑like mammals—appears in the fossil record just after the mass extinction that wiped out the non‑avian dinosaurs, but some studies push its origins back to about 81 million years ago.

Visually, *Purgatorius* looks like a mash‑up of a ferret and a squirrel, yet it possessed flexible ankle and wrist joints that would become hallmarks of later primates, enabling agile arboreal lifestyles.

This early experiment in primate evolution set the stage for the incredible diversity of tree‑dwelling mammals that would follow.

Steven Spielberg’s Jurassic Park came out in 1993 and was an immediate success. On its opening weekend in the United States and Canada, it raked in over $47 million, which went a long way to covering its budget of $60 million.

If the scientists who cloned the dinosaurs had had a more limited amount of cash, they might have looked around the modern world to find the dinosaurs’ closest living relatives—birds. And, as a stand-in for the terrifying T. Rex, they could have used one of its nearest kin—the chicken. Granted, the movie might not have had such an impact, but it would have been accurate.

We tend to think dinosaurs went extinct after a catastrophic event 66 million years ago. This is only true of some of them. We can divide dinosaurs into two groups: avian and non-avian. At least some of the avian dinosaurs survived to evolve into birds, and the non-avians disappeared.

Dinosaurs appeared between 243 and 233 million years ago in the Triassic period. They became the lords of the earth, a position they kept for millions of years before an asteroid smashed into the Yucatan peninsula. All the flesh-eating dinosaurs, such as the T. Rex, belonged to a subgroup known as Theropods. Members of this group had hollow bones and three digits on each foot, just like a chicken.

We have a problem with the term “dinosaur” because it covers a broad range of animals. When someone mentions dinosaurs in conversation, we imagine large vicious brutes such as T. Rex or the placid leaf-eating giant Brachiosaurus, but that is not always the case. So let’s explore ten reasons chickens are dinosaurs.

Related: 10 Fascinating Peeks Into The Daily Lives Of Dinosaurs

10 Tyrant Chicken King

Montana is rich in dinosaur fossils, and in 2003, Doctor Jack Horner (the man Doctor Grant was based on in Jurassic Park) found a T. Rex femur bone. A wonderful discovery, but it was too big to fit inside Horner’s helicopter. Taking a practical approach, he broke the femur in half and ferried it to the North Carolina Museum of Natural Sciences.

In North Carolina, the paleontologist, Doctor Mary H. Schweitzer, set to work on the bone. She discovered soft tissue inside. Unfortunately, any DNA had long since degraded, but Doctor Schweitzer could run tests on the proteins in the soft tissue. The analysis showed her that Tyrannosaurus Rex was more closely related to ostriches and chickens than any living reptile.

9 Bones

In our introduction, we said dinosaurs fall into two groups – avian and non-avian. Doctor John M. Rensenberger of the University of Washington and Doctor Mahito Watabe of the Hayashibara Museum of Natural Sciences in Japan did important work that strongly supported this idea.

They looked at the differences in the bone structure of modern mammals and birds. They found that in mammals, including ourselves, the tubes that bring nutrients to bone cells run parallel to each other like train tracks. When they looked at bird bones, they discovered no tube pattern.

Turning their attention to dinosaur fossils, they found two groups. Some dinosaurs—the flesh-eating Theropods—had the same pattern as modern birds like the chicken. Some, the ones that died out, had a pattern like modern mammals.

Fun Fact: The T. Rex had a wishbone, but you would need help in snapping it.

8 Eggs

As far as we know, dinosaurs laid eggs just like modern chickens and other birds. The fossil record is incomplete, but scientists are fairly sure that all dinosaurs laid eggs. As we are using T. Rex as our example of a chicken’s ancestor, we should make it clear that, so far, we haven’t discovered a T. Rex nest. But we have found nests of other Theropods. If T. Rex followed a similar pattern, which is very likely, she probably laid around twenty eggs.

Most of her hatchlings wouldn’t have reached their first birthday, but the ones that did survive would have put on around 1,700 pounds (771 kilograms) a year until they reached full adulthood at 20 years and reached a weight of about 9 tons. A recently hatched T. Rex would have been about the same size as a modern turkey.

7 Feathers

We don’t see flocks of chickens darkening the evening sky as they migrate for the winter. Chickens can fly, of course, but only for short distances and not very high. They prefer not to do it unless they have to.

We tend to link feathers with flight, but the ability to fly isn’t limited to animals with feathers. Feathers help a bird to fly, but this is an adaptation because feathers evolved for different reasons. A feather’s first uses were for insulation, communication (think of a peacock mating display), and acting as a water-repellant.

Many avian dinosaurs had feathers, and it seems many in the non-avian group had them too. The example that everyone uses to show the link between dinosaurs and birds is the Archaeopteryx, a genus of bird-like dinosaurs. This group of creatures lived in the late Jurassic period, about 150 million years ago, and most would have been around the size of a magpie.

A modern chicken would recognize them as fellow birds.

6 Feet

Going back to the movie Jurassic Park, one of the stars of the show was the Velociraptor. At nearly 7 feet (2.1 meters) tall, these were fearsome beasts. In reality, Velociraptors were not nearly so awe-inspiring. In truth, they were much closer in size to a chicken than to an ostrich.

Their similarity to chickens could also be seen if you looked at their feet.

Dinosaurs tended to have three-toed feet that were remarkably similar to modern birds. Analysis of fossil footprints shows that they moved in the same way too. In fact, early finders of dinosaur tracks often assumed that they were looking at bird tracks.

5 Parenting

Most birds take great care of their helpless young. A hen is no exception. She will teach her chicks how to scratch for food and drink, protect them from danger, and keep them warm.

We have fossil evidence suggesting that at least some dinosaurs behaved in the same way. This is perfectly logical, as hatchlings are very vulnerable. Even a baby T. Rex would have needed looking after until it could care for itself; it would need to learn about the world around it and look to its parent for protection.

Some paleontologists have suggested that an adolescent T. Rex probably went through a phase when it hunted differently from full adults. Not yet fully grown, it was probably faster and more agile than mom or dad and so went off hunting different beasts. Teenagers!

Still, like teenagers today, a young T. Rex seems to have moved around with the rest of his family, although we don’t know if he was reluctant to be seen in public with them.

4 Color

Most of us might think that dinosaurs were quite drab—a little like an elephant, perhaps. But feathered dinosaurs could be just as gaudy as modern birds. We know this because fossilized feathers contain melanosomes. Very simply, melanosomes process and store melanin and give an animal its color.

By studying how melanosomes are arranged in different sizes and densities, researchers can accurately recreate what color or combination of colors the dinosaur had.

It’s a pity that we have so few samples to work from, but there are enough to show that a feathered dinosaur could be just as glorious as a Brahma chicken. And for the same reasons—mating displays, communication, and, perhaps, camouflage are all factors for such bold color schemes.

3 Air Sacs

If you’ve ever picked up a chicken, you will have noticed that it is lighter than it should be. This is because birds have air sacs extending from their respiratory system. This system makes breathing more efficient, which is very useful when a bird needs to exert itself and makes their bodies lighter.

But chickens and other birds didn’t evolve this system; they inherited it from dinosaurs. Some dinosaurs were tiny, but others reached truly incredible sizes. The Argentinosaurus, for example, was at least 98 feet (30 meters) long and weighed at least 72 tons.

Some dinosaurs could grow to such incredible sizes due to air sacs making their bodies lighter and more efficient than they would otherwise be.

2 Wings

A chicken’s wings evolved from short forearms that animals used to capture small prey because their ancestors were jumping into the air to grab things above them. Chickens are a good example of an early stage of this process because they often flutter up rather than properly fly.

If you look closely at a chicken wing, you will see that it is simply a collection of fingers fused and folded against the arm bone, just like its dinosaur relative—a Velociraptor.

1 Tooth or Beak?

The expression “rarer than a hen’s teeth” indicates that chickens don’t have teeth. Not only does this save on dental care, but it also makes flying easier—not that chickens have made much of this advantage.

Many of our chicken’s earliest relatives did have teeth, but a beak made things easier. Some Theropod dinosaurs also developed beak-like structures.

An interesting example of this movement from teeth to beaks comes from China. There, a team discovered a dinosaur named Limusaurus that roamed around in the late Jurassic period 160 million years ago. A young Limusaurus had teeth, but as it grew older, it lost them, and its jaw morphed into a beak. This must have been a very strange sight and somewhat painful for the adolescent beast.