The only place non-avian dinosaurs didn't seem to live was in the ocean as all major marine reptiles weren't dinosaurs but some other archosaur or Mozasaurs which are related to modern day monitor lizards. Dinosaurs have been discovered on every single continent including Antarctica, in every type of biome from desert to forest to steppe to river deltas. Some of the best specimens have come from river watersheds such as the hell creek formation or Morrison because the conditions on river banks is the best for preserving large body animals but plenty of other formations exist away from river banks. EDIT: clarifications. So I've seen a lot of the same comments so I'll leave a reply here to these questions. Antarctica at the time of the dinosaurs (the Mesozoic) would not have been covered in ice, it also would not have been on the south pole, rather closer to modern day South Africa. That being said, dinosaurs have been discovered in what would have been their Arctic Circle where it would have snowed regularly, experienced very cold temperatures in the winter and had 1-3 months of no sun. Dinosaurs that lived in this region permanently had special adaptations such as Truodonts in this region being much bigger than their southern cousins while a type of Tyrannosaurus (not THE T. Rex but a relative) had a smaller body. It's also worth mentioning that dinosaurs were not cold blooded rather a sort of in between called Mezotherm. To what extent depends heavily on the dinosaur. Not all ancient reptiles that lived in the Mesozoic was a dinosaur and in short the different is taxonomy, the relationships between species. All animals classified as dinosaurs have a distinct common ancestor that separates them from all other reptiles. One interesting thing is the fact that all dinosaurs, from triceratops to deinococcus to modern barn owls have a very specific pelvis that is unlike any other reptile. Plesiosaurs, Ichthyasaurs, Mozasaurs, and Ptarosaurs are not dinosaurs as they do not share the same ancestor as all dinosaurs, and in the case of the aquatic reptiles, split off from dinosaurs long before dinosaurs themselves became a distinct Clade. Answer from areigon on reddit.com
Reddit
reddit.com › r/showerthoughts › dinosaurs existed for a good 165,000,000 years meanwhile we’ve only existed for some 300,000
r/Showerthoughts on Reddit: Dinosaurs existed for a good 165,000,000 years meanwhile we’ve only existed for some 300,000
January 3, 2024 -
I never really see anyone talk about just how long dinosaurs ruled the Earth for compared to our measly existence. It really is just due to the most obscene chance that we exist… The kings of the world wiped out by some random rock hurtling through space that happened to hit our tiny planet. I can’t help but wonder how different things would be today had they survived.
edit: yeah, it really was just a shower thought. People have been quick to point out how meaningless the term ‘dinosaur’ is in this comparison
Reddit
reddit.com › r/askscience › did dinosaurs roam the entire planet or did they live in certain parts? and if so, where did they predominantly live and why?
r/askscience on Reddit: Did dinosaurs roam the entire planet or did they live in certain parts? And if so, where did they predominantly live and why?
August 15, 2021 -
For example, did they live near forest, water, hot/cold, etc.
Top answer 1 of 8
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The only place non-avian dinosaurs didn't seem to live was in the ocean as all major marine reptiles weren't dinosaurs but some other archosaur or Mozasaurs which are related to modern day monitor lizards. Dinosaurs have been discovered on every single continent including Antarctica, in every type of biome from desert to forest to steppe to river deltas. Some of the best specimens have come from river watersheds such as the hell creek formation or Morrison because the conditions on river banks is the best for preserving large body animals but plenty of other formations exist away from river banks. EDIT: clarifications. So I've seen a lot of the same comments so I'll leave a reply here to these questions. Antarctica at the time of the dinosaurs (the Mesozoic) would not have been covered in ice, it also would not have been on the south pole, rather closer to modern day South Africa. That being said, dinosaurs have been discovered in what would have been their Arctic Circle where it would have snowed regularly, experienced very cold temperatures in the winter and had 1-3 months of no sun. Dinosaurs that lived in this region permanently had special adaptations such as Truodonts in this region being much bigger than their southern cousins while a type of Tyrannosaurus (not THE T. Rex but a relative) had a smaller body. It's also worth mentioning that dinosaurs were not cold blooded rather a sort of in between called Mezotherm. To what extent depends heavily on the dinosaur. Not all ancient reptiles that lived in the Mesozoic was a dinosaur and in short the different is taxonomy, the relationships between species. All animals classified as dinosaurs have a distinct common ancestor that separates them from all other reptiles. One interesting thing is the fact that all dinosaurs, from triceratops to deinococcus to modern barn owls have a very specific pelvis that is unlike any other reptile. Plesiosaurs, Ichthyasaurs, Mozasaurs, and Ptarosaurs are not dinosaurs as they do not share the same ancestor as all dinosaurs, and in the case of the aquatic reptiles, split off from dinosaurs long before dinosaurs themselves became a distinct Clade.
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I highly recommend PBS Eons YouTube channel. They have some amazing videos on the lives and habitats of dinosaurs. Apparently they even lived in the Arctic circle. (Arctic circle was a much different place back then, but it still lacked sunlight for months at a time and was extremely cold)
Videos
r/Dinosaurs on Reddit: Isn't it crazy how long dinosaurs actually ...
15:02
The Entire Dinosaur Era Explained in 15 Minutes... - YouTube
The Very Long Time of the Dinosaurs! | History of Life ...
19:03
What Was the Earth Like When Dinosaurs Were Around? - YouTube
09:55
How Long Did The Dinosaurs Actually Survive After The Asteroid? ...
Reddit
reddit.com › r/paleontology › the vastness of time that has gone since the dinosaurs roam the earth.
r/Paleontology on Reddit: The vastness of time that has gone since the Dinosaurs roam the earth.
March 10, 2024 -
I'm sitting here and looking at mountains, buildings and roads and it's hard to fathom that for hundreds of millions of years ago, these lands were different and where giant reptiles roaming here. Just to think back to 70 millions years ago is too much for a human mind to comprehend. It's both fascinating and surreal.
Reddit
reddit.com › r/dinosaurs › year of the dinosaurs?
r/Dinosaurs on Reddit: Year of the dinosaurs?
June 17, 2024 -
I'm looking to find the actual years of the dinosaurs (2million BC, idk) but all I find is "dinosaurs lived 200 thousand years ago."
I'm trying to add it to a timeline I'm working on but can't find definitive ranges of dates. Can anyone help?
Edit to add: thanks for the people who genuinely answered. I didn't understand, but now I do 🦖
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The earliest dinosaurs lived at least 233 million years ago, in the Triassic. Non-avian dinosaurs died out at the end of the Cretaceous, 66 million years ago, and avian dinosaurs are still alive today.
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Non avian Dinosaurs were around during the mesozoic era, and this era is split between three time periods. The Triassic Period from 250 to 201million years ago. The Jurassic Period 200 to 145 million years ago. And the Cretaceous Period 145 to 66 million years ago.
Reddit
reddit.com › r/nostupidquestions › how come dinosaurs lived for 165 million years and never achieved any scientific progress but humans went from monkey-like creatures to spaceships in only 4 million years?
r/NoStupidQuestions on Reddit: How come dinosaurs lived for 165 million years and never achieved any scientific progress but humans went from monkey-like creatures to spaceships in only 4 million years?
September 22, 2022 -
I just googled when the first Australopithecus appeared on earth and apparently it is estimated to be 4 million years ago. How come the Earth environment led us to evolve so "quickly" (relatively speaking) but during this ~100 mi years that the dinosaurs were around never did anything of this sort to them?
Top answer 1 of 70
185
Insects are on earth since 400m years, bacteria even more, "high intellect" is obviously not a required trait for survival and reproduction for many species
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The ancestors of birds went from walking to flying over seventy million years ago, so why haven't slugs evolved flight yet? Well, that's not how it works. dinosaurs are under just as much obligation to make scientific progress as slugs are under an obligation to fly. If it doesn't happen in their lineage due to lack of pressure, it doesn't happen, right?
CK-12 Foundation
ck12.org › all subjects › earth science › age of earth › how long did dinosaurs roam the earth?
Flexi answers - How long did dinosaurs roam the Earth? | CK-12 Foundation
September 11, 2025 - Dinosaurs roamed the Earth for a really long time! They first appeared during the Triassic period, about 230 million years ago, and they were around until the end of the Cretaceous period, about 65 million years ago. That means dinosaurs were on Earth for around 165 million years!
Discover Magazine
discovermagazine.com › home › the sciences › a complete dinosaur timeline to extinction: how long did they roam earth?
A Complete Dinosaur Timeline to Extinction: How Long Did They Roam Earth? | Discover Magazine
June 21, 2023 - Dinosaurs roamed Earth for millions of years, during a major geologic era known as the Mesozoic.
Encyclopedia Britannica
britannica.com › science › earth science, geologic time & fossils › dinosaurs
How Long Did Dinosaurs Live? | Extinct, Time Span, & Facts | Britannica
June 20, 2025 - Dinosaurs roamed the Earth for an impressive span of about 165 to 180 million years. They first appeared about 245 million years ago during the beginning of the Middle Triassic Epoch.
Reddit
reddit.com › r/paleontology › why do so many sources say that dinosaurs ruled the earth for 165 million years?
r/Paleontology on Reddit: Why do so many sources say that dinosaurs ruled the earth for 165 million years?
August 5, 2025 -
If dinosaurs are roughly 243 million years old and the extinction event was roughly 66 million years ago... that's 177 million years
Yet i've seen 165 million years quoted in kids books, documentaries and many websites
Can someone explain what I'm missing? 🙏 🦖
Top answer 1 of 18
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This is an older figure from before dinosaurs were found at earlier points in the Triassic. At the time many of these claims were being made, Eoraptor was the oldest known dinosaur at 230-228 million years old. The idea that dinosaurs emerged in the Middle Triassic is a very recent development and still requires further study to confirm, given how similar many dinosauromorphs were to the genuine article. Having said that, even using the knowledge of the time I still disagree with the sentiment and think you can only really say dinosaurs 'ruled' the Earth for around 135 million years, as they only truly took over their ecosystems after their Pseudosuchian competitors went extinct at the end of the Triassic Era.
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I think the language here is important, how long were dinosaurs around vs how long did they thrive (rule) for. The first known dinosaurs turned up 177 million years ago but they didn’t dominate right away, I believe there was an extinction event at the end of the Triassic which dinosaurs benefited from. That helped them get a foothold and become the dominant species
Reddit
reddit.com › r/showerthoughts › considering that they have existed for a timespan way longer than we have, dinosaurs were sort of the main characters of earth.
r/Showerthoughts on Reddit: Considering that they have existed for a timespan way longer than we have, dinosaurs were sort of the main characters of Earth.
September 11, 2023 -
Dinosaurs had been around on Earth for about 165 million years compared to Homo sapiens that have only existed for about 200,000 years. In some perspective, the dinosaurs were a more significant part of Earth's history than we ever have been so far. They were the dominant clade on the planet for over three major time periods and many individual species of them existed for millions of years themselves, and their descendants still exist to this very day.
Dino-walk
dino-walk.com › news › when-did-dinosaurs-live.html
When Did Dinosaurs Live? Timeline & Prehistoric Facts
When did dinosaurs live? This question fascinates scientists and dinosaur enthusiasts alike. Dinosaurs roamed the Earth for millions of years, long before modern humans appeared. Non-bird dinosaurs lived between approximately 245 and 66 million years ago, during a period known as the Mesozoic Era.
Active Wild
activewild.com › home › how long were dinosaurs on earth? dinosaur history & the mesozoic era
How Long Were Dinosaurs On Earth? A Brief History Of The Mesozoic Era
April 22, 2017 - How long were dinosaurs on Earth. Dinosaurs were on Earth for between 165 & 177 million years from the mid Triassic to the end of the Cretaceous period.
Quora
quora.com › When-did-dinosaurs-roam-the-Earth
When did dinosaurs roam the Earth? - Quora
There are six named geological periods during which dinosaurs have existed. Fair warning, if this is a homework question, you’ll probably only get credit for the first three. 1. Triassic, 251–201 million years ago (mya).
Environmental Literacy Council
enviroliteracy.org › home › how long did dinosaurs roam the earth?
How long did dinosaurs roam the earth? - The Environmental Literacy Council
March 23, 2025 - Dinosaurs, those awe-inspiring giants and fascinating creatures, roamed the Earth for approximately 165 million years.
Quora
quora.com › How-old-was-Earth-when-dinosaurs-were-around-and-did-any-live-to-see-humans-come-about
How old was Earth when dinosaurs were around and did any live to see humans come about? - Quora
Dinosaurs first emerged a little while after the devastation of the Permian Mass Extinction. We aren't absolutely positive of the time, but it was between 233 and 240 million years ago. That means the Earth was rough...
A-Z Animals
a-z-animals.com › animals home › articles › how long were dinosaurs on earth?
How Long Were Dinosaurs on Earth? - A-Z Animals
May 5, 2025 - Dinosaurs first arose in the Middle to Late Triassic Period about 230 to 240 million years ago. At this time, the landmass of Earth was one large continent called Pangea. A massive extinction event called the Permian mass extinction occurred ...
Live Science
livescience.com › animals › extinct species › dinosaurs
A brief history of dinosaurs | Live Science
July 6, 2021 - Dinosaurs ruled the Earth for 135 million years. There were many types of dinosaurs, in all shapes and sizes.
Reddit
reddit.com › r/dinosaurs › it's easy to forget just how long the age of dinosaurs was. while it might seem like tarbosaurus & t. rex lived alongside each other, based on what we know, tarbosaurus lived 2-4 million years earlier than its bigger cousin.
r/Dinosaurs on Reddit: It's easy to forget just how long the Age of Dinosaurs was. While it might seem like Tarbosaurus & T. rex lived alongside each other, based on what we know, Tarbosaurus lived 2-4 million years EARLIER than its bigger cousin.
February 28, 2025 - Mammals ruled after the dinosaurs bit the dust 66 million years ago, while Dinosaurs have been around for 250 million years at least. Although the Precambrian era is probably the longest out of all of Earth’s geologic time periods.
USGS
usgs.gov › faqs › where-did-dinosaurs-live
Where did dinosaurs live? | U.S. Geological Survey
During the 165 million years of dinosaur existence this supercontinent slowly broke apart. Its pieces then spread across the globe into a nearly modern arrangement by a process called plate tectonics.
Quora
quora.com › How-long-were-dinosaurs-on-Earth-compared-to-humans
How long were dinosaurs on Earth compared to humans? - Quora
Answer (1 of 44): Okay, first let's ... be prefaced by what you mean by “human”. Dinosaurs were around for roughly 150-160 million years, c......