Ancient Turtles Lived Alongside Dinosaurs in Prehistoric Times [Including Softshelled Turtles]

Believe it or not, there was a time that turtles and dinosaurs coexisted peacefully on earth. Paleontologists say that turtles and dinosaurs had shared natural habitats even before dinosaurs became extinct. Turtles are a reptile family that may be found on all continents except Antarctica. They include species living in salt and fresh water and those who live on lands, such as sea turtles, terrapins, and tortoises. Turtles have survived many devastating mass extinctions, including one that wiped off the dinosaurs, which have been around for tens of millions of years.

Did Turtles Live With Dinosaurs – All About Ancient Turtles

Did turtles live with dinosaurs? Yes. The earliest known records of sea turtles appearing on earth happened in the Jurassic period. Prehistoric turtles lived with dinosaurs until the dinosaurs became extinct 65 million years ago.

The fossil record, a window into Earth’s past, places turtles and dinosaurs within the same layers of sediment, indicating contemporaneous existence. This overlapping timeline primarily covers the span of the Mesozoic era, often labeled as ‘the age of the dinosaurs’, a time when these creatures reigned supreme.

However, turtles’ evolutionary pathways extend further back into the Paleozoic era, emphasizing their resilience and longevity over time. Despite living alongside the formidable dinosaurs, turtles adapted to a diverse set of environmental conditions presented during the prehistoric epochs.

The Mesozoic Era unfolded over three periods: the Triassic, Jurassic, and Cretaceous. Dinosaurs emerged during the Triassic Period. Turtles also appeared in the Triassic Period, carrying on throughout the Mesozoic.

The Triassic Period fostered early reptiles. Reptiles diversified extensively into multiple forms. Multiple forms included both dinosaurs and turtles.

Fossils stand as historic evidence. Evidence facilitates the study of ancient life. Paleontology interprets this ancient life, connecting the past to present biodiversity.

Archelon swam alongside other marine giants. Other marine giants, like plesiosaurs and mosasaurs, inhabited the Mesozoic seas. Mesozoic seas supported vast aquatic ecosystems.

The Yixian Formation offers abundant fossils. Fossils from this formation feature both turtles and feathered dinosaurs. Feathered dinosaurs support theories on avian evolution. The Chicxulub crater marks a significant geological impact. Geological impacts catalyze environmental changes. Environmental changes at this crater delineate the Cretaceous-Paleogene mass extinction.

Extinction events reshape life on Earth. Life on Earth during the Mesozoic included a rich array of reptiles. Reptiles’ fossils found in various formations confirm prolonged cohabitation.

Continental drift reorganized global geographies. Global geographies influenced species’ adaptations and survival. Adaptations and survival of Mesozoic creatures faced constant challenges. Carbon dating deciphers fossils’ ages. Fossils’ ages validate the overlapping existence of turtles and dinosaurs. Turtles’ broad distribution exhibited survival beyond the dinosaurs’ extinction.

Turtles cohabited Earth with dinosaurs. Earth’s ancient history reveals continuous change. Change encompassed the rise and extinction of many species, yet turtles endured alongside the dinosaurs for millions of years.

Today, every living turtle ties our modern world to its prehistoric past—a testament to their cohabitation with dinosaurs. The enduring turtles serve not only as living fossils, but as reminders of life’s tenacity and adaptability amidst Earth’s ever-changing landscape.

This article will discuss how old turtles are and how they came to coexist with dinosaurs here on earth. We will also discuss more on their relationships with the dinosaurs and where they differ from them. Lastly, we will compare and contrast the prehistoric turtles of yesterday to the turtles of today.

Did Turtles Exist Before Dinosaurs?

Scientists have claimed that dinosaurs existed with turtles. Here are some of the proof points they have given as evidence. 

Turtles Roamed The Same Earth As Dinosaurs

Turtles evolved 230 million years ago, mostly during the Triassic Period, but their exact origins are unknown. Some experts believe turtles are more closely linked to lizards and snakes, while others feel they belong in the archosaurs, including crocodiles, pterosaurs, dinosaurs, and birds.

Turtles survived the Triassic Period’s great extinction, which wiped out enormous swaths of life and ushered in the dinosaur era. Turtle diversity was at an all-time low at the time. The numbers of turtle species did not begin to increase until the Cretaceous period, which began 145 million years ago. It stayed high until another catastrophic extinction, one of the most violent ever witnessed on the planet.

The Asteroid Has Greatly Benefitted The Turtles

The dinosaurs suffered greatly during the striking of this asteroid on earth, but it did not harm nor damage the turtles.

The dinosaurs and countless other species perished in this magnificent catastrophe, which was assumed to have been triggered by an asteroid crashing to earth. Still, turtles not only survived, but their diversity seemed to expand. Some turtle species did become extinct at this period, but many others did not. When compared to groups like dinosaurs or lizards, the number of species that remained is impressive.

There was a significant peak in the number of turtle genera over the next five million years. Water-dwelling animals were somewhat safe from whatever was killing the land vegetation and dinosaurs. In short, the turtles survived what caused the dinosaurs’ demise on earth.

How The Turtles Survived The Big One

A meteorite hit most certainly triggered the global extinction event that wiped out the dinosaurs, known as the K-T boundary, because of its unique mark in rock layers. However, the exact sequence of events is still questioned.

Some academics believe the sky was darkened by a series of world-shattering volcanic eruptions, which may or could not have been caused by the meteor. Like other burrowing and water-dwelling creatures, the turtles survived the dinosaur-killing whole-Earth mass extinction, which wiped out 90 percent of all land-dwelling animal and plant species, including land-dwelling turtles.

Small animals with a slow metabolism that live in the water, such as turtles, are thought to do well over the K-T barrier. 

These turtles ate soft vegetation and crustaceans and resided in North American lakes and streams. 

Though they aren’t closely linked to any surviving turtle species, they would have looked like today’s painted or cooter turtles.

They were part of a broad group of turtles known as baenids, of which at least eight survived the mass extinction only to perish subsequently due to other causes. (Source)

The Duality of Ancient Turtles – Proganochelys Quenstedti And Archelon

Proganochelys quenstedti, one of the earliest known turtles from the late Triassic Period, approximately 210 million years ago, represents a cornerstone in turtle evolution. Its heavily armored shell and non-retractable head exemplify primitive traits, situating turtles as one of the most ancient reptilian lineages, contemporaneous with the rise of dinosaurs.

This genus provides a vital link in understanding the evolutionary history of reptiles, showcasing the deep roots and progressive adaptation of turtles over time.

Contrastingly, Archelon, from the late Cretaceous Period about 75 million years ago, displays the evolutionary advancement and marine specialization of turtles. With an impressive size exceeding four meters and adapted flipper-like limbs, Archelon navigated prehistoric seas, indicating a significant diversification from their early ancestors.

Their coexistence with dinosaurs highlights turtles’ ecological success and adaptability in the marine realm while dinosaurs occupied terrestrial ecosystems. The transition from Proganochelys to Archelon illustrates turtles’ enduring presence and resilience through substantial evolutionary changes.

Are Turtles Dinosaurs and Part Of The Dinosaur Family?

Paleontologists connected turtles to dinosaurs for several reasons. Here are some of those reasons.

They Existed Together, But Not Closely Related

Some researchers have raised the question of turtles being related to the dinosaurs because they existed together until the mass extinction of dinosaurs happened. Thus, more and more people have questioned the placement of turtles in the reptilian phylogeny.

For various reasons, the place of turtles in the reptile phylogeny has always been a point of contention. Turtles are one of a kind among reptiles, thanks to their significantly modified body structures (e.g., shells) and the fact that they are anapsids.

Diapsids include dinosaurs and all reptiles that lived during the Mesozoic epoch and non-turtle reptiles that are still alive today. Turtles have been around for a very long period as well. (Source)

The oldest turtle fossil was discovered in the declining years of the Permian epoch, before dinosaurs or any other extant reptile groups had ever emerged.

According to expert agreement, the archosaurs (which include dinosaurs, crocodilians, pterosaurs, and birds) are more closely related to turtles than the lepidosaurs, according to expert agreement (the lizards, snakes, tuatara, and mosasaurs).

Turtles’ evolution predates that of any other living reptiles by at least 7 million years. Thus it’s difficult to tell where they fit into the reptilian family tree. 

One thing we have to remember, however, is that everything living on this earth is related to one another. Still, if we talk about close relations, then turtles are not as closely related to dinosaurs as other animals.

Reptiles are near as diversified as mammals in terms of species. The only problem with reptiles is that they are mostly gone, leaving only birds, turtles, lizards, snakes, tuataras, and crocodiles. The fact that something is reptile does not imply that it is linked to dinosaurs.

Recommended Reading:

● I’ve written a whole article about whether turtles are related to dinosaurs, which describes how turtles and crocodiles share an almost sibling relationship on a molecular level
● If you are interested in what features all dinosaurs have in common, I’ve written an article which explains, for instance, that all dinosaurs laid eggs and that fossil eggs have been found all over the world and on all continents

Why Some People Believe They Are Related

Turtles, which are thought to have existed for a long time, are among the simplest and most common reptiles on the planet today. According to scientists, turtles coexisted with dinosaurs roughly 110 million years ago until the K-Pg mass extinction, which wiped out the dinosaurs.

Archosaurs include crocodiles, dinosaurs that have died out, and pterosaurs, about animals with a hole between the eye socket and nostril. Turtles and these archosaurs had a common ancestry, according to a hypothesis supported by DNA evidence.

Another theory is that turtles are anapsids, or creatures with no side holes in their skulls, whereas dinosaurs are diapsids, creatures with skulls with two openings. It is crucial because diapsids are thought to have developed from anapsids.

Turtles are demonstrated to be connected to dinosaurs in both of these hypotheses. It is possible that turtles are descended from the same ancestor as dinosaurs or that dinosaurs are more advanced versions of the turtles’ forebears.(Source)

What Does the Discovery of Leviathanochelys Aenigmatica Suggest About the Evolution of Turtles?

The recent discovery of Leviathanochelys aenigmatica provides valuable insights into the evolution of turtles. This finding not only emphasizes that turtle gigantism was not exclusive to the Americas but also highlights the possibility of more giant turtle species existing in Europe.

With a body length of 3.7 meters, Leviathanochelys aenigmatica may not surpass the length of Archelon, the largest known turtle species, but it compensates with its remarkable width, solidifying its status as one of the largest turtles in history.

The co-author of the study, Dr. Ángel Hernández Luján, expresses optimism that the European continent holds further revelations regarding giant turtle species. While fragmentary remains of large marine turtles have been unearthed throughout Europe, none have been as complete as Leviathanochelys.

This suggests that the study of Leviathanochelys aenigmatica is just the beginning, opening the door for the eventual discovery of additional large-bodied sea turtle species from prehistoric eras.

This finding demonstrates that turtle gigantism was not confined to a specific region or continent but rather a widespread phenomenon. These giant turtles, exi

Comparing Ancient Turtles To Modern-Day Turtles

There is no doubt that ancient turtles and modern-day turtles are quite alike. Here are some of the contrasts and comparisons.

Turtles Have Evolved And Adapted To Its Environments

In some ways, turtle evolution is a simple story to follow: the fundamental turtle body design emerged early in the history of life, during the late Triassic period, and has remained mostly constant until now, with the normal changes in size, habitat, and adornment.

Like most other creatures, the evolutionary turtle tree contains many missing links, some of which have been located. In contrast, others have not, false starts and short-lived instances of gigantism.

Ancient turtles and tortoises were largely fixed into their contemporary body patterns by the early Jurassic period, around 200 million years ago, though there was still potential for innovation. 

Archelon and Protostega, two sea giants, measured about 10 feet long from head to tail and weighed around two tons, were the most famous turtles of the Cretaceous epoch.

As you might think, these massive turtles had broad, muscular front flippers to help drive their massive bodies through the water; their nearest living cousin is the considerably smaller Leatherback turtle, which weighs less than a ton. (Source)

Hard Shells That Transcended Evolutions

One of the most common similarities between ancient turtles and modern-day turtles is their hard shells.

Leatherbacks were known to have no shells covering their backs. While the leatherback’s ancient ancestors were diversifying, other stem turtle groups continued to refine an armored shell, eventually changing to a streamlined body plan with a robust and light plastron and carapace.

Apart from the leatherback, Ctenochelys acris, an 80 million-year-old species from the southern United States, is a potential ancestor of all modern-day sea turtles. It shares traits with both contemporary sea turtles and freshwater snapping turtles, such as huge back flippers that would have been utilized for propulsion, which modern sea turtles lack.

The Emergence Of The Shelled Turtles We Know Today

This table provides a brief history of the evolution of sea turtles, specifically focusing on the Chelonian turtles and their dietary habits. This includes the changes that occurred during the Eocene-Oligocene Transition and how these changes impacted different species of turtles.

Evolutionary Timeline	Species and Characteristics	Diet
40 million years ago	The first ‘real’ shelled marine turtles, known as Chelonian turtles, appeared. They could resist formidable marine predators such as sharks, lepidosaurs, and mammals thanks to their armor.	Varies based on species
Present Day	Six Chelonian species are still alive today. The turtles that arose during this period are extremely similar to those that exist now.	Varies based on species
34 million years ago (Eocene-Oligocene Transition)	The ancestor of modern green sea turtles, or the Chelonia mydas, was probably a generalist omnivore. This period saw the evolution of algae-grazing green turtles and warm-blooded, sea cucumber-hunting flatback turtles, known as the Natator depressus.	Algae for green turtles and sea cucumbers for flatback turtles.
Present Day	Loggerhead turtles have sharp teeth and beaks for crushing mollusks and shellfish. Hawksbill turtles can survive nearly completely on sea sponges. Olive ridleys eat jellyfish, fish eggs, echinoderms, and shrimp. Kemp’s ridley turtles are the only true omnivore sea turtles, eating mollusks, jellyfish, fish, and seaweed.	Specific to each species. For example, sea sponges for Hawksbill turtles, jellyfish and other sea creatures for Olive ridleys, and a mix of mollusks, jellyfish, fish, and seaweed for Kemp’s ridley turtles.

The Turtles That We Know Today

In the last 3 million years, the earth’s form has shifted. The uplifting of Central America, which was previously fully submerged under the sea, cut off communities of turtles in the Pacific and Atlantic oceans. Additionally, as upwellings of cold current flow at the Cape of Good Hope and Tierra Del Fuego (South America’s southernmost tip) prevent many of these warm-blooded creatures from rounding the continents’ tips.

The worldwide sea turtle gene pool has been influenced by the isolation of the oceans, which was not far enough in the old days to cause speciation. We are witnessing the early phases of speciation in loggerhead turtles, as there are now numerous genetically different populations of loggerheads, most notably when comparing Pacific and Atlantic loggerheads.

Green turtles also take a similar pattern, which is more evident due to their more varied shell markings. Even though green turtles are classified as a single species, a brief internet search exposes the controversy surrounding them, with names like “Agassizi turtle,” “black sea turtle,” and “Galápagos green turtle” all appearing as proposed subspecies.

Conclusion

There is no doubt that turtles and dinosaurs have existed peacefully with each other. When the dinosaurs perished, the turtles did not share the same fate as theirs and thus could evolve and last until today. Turtles are known to be one of the oldest living animals on earth, and their fate of surviving when the bigger dinosaurs did not, is always going to fascinate paleontologists and people invested in dinosaurs for a long time.

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