Skip to main content

What Caused the Dinosaurs To Die?

Angela loves history and feels it is essential to our future to know the past—or else we're destined to repeat it.

Mosasaurs were large aquatic dinosaurs that are believed to have lived during the Cretaceous period and became extinct along with the dinosaurs.

Mosasaurs were large aquatic dinosaurs that are believed to have lived during the Cretaceous period and became extinct along with the dinosaurs.

How Did Dinosaurs Become Extinct?

The extinction of the dinosaur is one of the world's mysteries that we will never honestly know — most of what scientists believe in having destroyed an entire species is just theories, at best. Limited knowledge helps form the arguments we have of our solar system and our planet's history. Even with this knowledge, many of the hypotheses are just wild guesses. Some are ludicrous and involve the idea that the dinosaurs became extinct because their brains were too small, which caused them to be unable to adapt to a changing world. Since things with even smaller brains have survived, there had to be more than just little brains at work. There are also more plausible theories, as well. One thing that most scientists agree upon is that there was one catastrophic event that caused many animals, not just dinosaurs, to die at the same time. Here are some of the most popular theories about what led to the extinction of the dinosaurs.

A Meteor Hitting the Earth

Created by NASA to show what may have happened millions of years ago.

Created by NASA to show what may have happened millions of years ago.

Did a Meteor Kill the Dinosaurs?

One of the most well-respected theories is the Asteroid Collision Theory, which was brought to attention by Walter Alvarez in 1980. He believed that an asteroid impacted the Earth 16.5 million years ago. Many agree to disagree about how the asteroid affected the EEarthand what caused the dinosaurs to become extinct.

Dust: Some scientists believe that a vast dust cloud blocked the sun's rays for several years when the meteor hit the Earth. Due to the lack of direct sunlight, much of the vegetation died off. Since dinosaurs were losing their primary food source, they could not survive. Although some scientists believe that the dust caused more than just the vegetation to die, it is unknown whether the dust would have settled after a few months or a few years. Since there are animals who did survive the Cretaceous Period, we know that not all the vegetation died off. What would account for some animals dying but not others?

A Deep Chill: One theory is that the dust caused a deep chill. When the meteor hit the Earth and caused dust to rise, the dust blocked the sun. Since the dust blocked the sun, not only did the vegetation die off, but the entire world began to cool down, leaving the Earth a very dark, cold place. Dinosaurs were not built to withstand long cold periods because most were cold-blooded. Consequently, they could not regulate their body heat and essentially froze to death.

Greenhouse Effect: Ironically, although some scientists state that the Earth cooled, others argue that the whole Earth warmed up rapidly due to the meteors hitting the ground. The dust surrounding the Earth and a sudden volcanic eruption triggered a greenhouse effect, which ultimately led to the EEarthbecoming overheated. Since cold-blooded creatures cannot regulate their body temperatures, overheating is as dangerous as freezing to death. Freezing to death may have also killed off some warm-blooded animals since many of them can only survive in certain climates.

Triceratop Bones

Triceratops were named because of their three horns.

Triceratops were named because of their three horns.

Did Dinosaurs Die in a Flood?

The Great Flood: Not all scientists agree that a meteor hit the earth. They believe that there was a different catastrophic event, such as a flood. Many people assume it was by the Great Flood, which Christians attribute to the story in the Bible about Noah's Arc, and other religions attribute to their corresponding tale. They believe that all animals except dinosaurs were protected. Although there is evidence that a Great Flood did occur, many scientists believe that the flood that killed off the dinosaurs was more gradual.

A Gradual Flood: Over time, the continents began to separate, slowly becoming the landmasses we know today. As this occurred, sea levels rose, this began to flood out the low-lying land, limiting vegetation and shelter for many dinosaurs. They believe that flowering plants became more abundant when this happened, which made way for mammals to flourish.

The animals most related to the dinosaurs are birds and marine life. A gradual flood would not have hindered the existence of either of these creatures but may have restricted land roaming dinosaurs since birds would have been able to find homes even with a flooded floor. Marine life, like lobsters, turtles, and sharks, which are still around today, would have also survived.

Many Questions Go Unanswered: Although not all sea creatures were as lucky during this event and did become extinct, some land animals somehow survived this period. We know that gradual flooding did occur around the same time as the dinosaurs, which is believed to be before the Great Flood. It is more likely that a more gradual decline in dinosaurs becoming extinct occurred than them being killed abruptly by some unknown event.

Tyrannosaurus Rex

One of the fiercest, most scary dinosaurs, now extinct.

One of the fiercest, most scary dinosaurs, now extinct.

Did a Sudden Severe Weather Change Kill the Dinosaurs?

We know the earth went through some significant changes when the dinosaurs died that had nothing to do with a flood or meteors. They believe that the event was a natural solar cycle of our world. Interestingly, they share many similar attributes despite none of these theories being about floods or meteors.

The Parting of the Seas: Seas did develop over time, and there has been a change in landmass. Due to the rapid shift in land and water, a build-up of Carbon Dioxide (CO2) abruptly occurred in the atmosphere. If the earth were to have increased levels of CO2, then the earth's temperature would rise, and the land would become extremely hot. As stated in many of the theories, their cold-blooded nature essentially killed the dinosaurs. Their extinction would have affected many animals both in the sea and earth, who cannot survive in a carbon dioxide-rich atmosphere.

Volcanic Activity: There is also a belief that a sudden surge of volcanic activity occurred around this time, unlike any we have seen. Some theorists believe that this was triggered by a meteor shower, while others believe it was a natural event that could happen again. If many volcanoes were to erupt simultaneously, this would cause massive destruction to the earth's ozone layer. Once the destruction of the ozone layer occurred, the atmosphere would allow an unhealthy level of ultraviolet radiation to reach the earth's surface. The ultraviolet radiation ultimately would kill the dinosaurs. Yet the question remains, then how come there are some remaining animals from that period?

No one will ever honestly know how the dinosaurs became extinct. One fact remains brighter than the rest; many of these theories coincide. The truth probably lies somewhere, where all of these theories collide.


Gibbons, Gail. Dinosaur Discoveries: Holiday House; New York. 2005

National Wildlife Federation. Ranger Rick's: Nature Scope: Digging Into Dinosaurs: Chelsea House Publishers, Philadelphia. 1997.

Scroll to Continue

Norman, David, Ph.D., and Angela Milner, Ph.D. Eyewitness Books: Dinosaur:Alfred A Knopf; New York. 1989.

© 2012 Angela Michelle Schultz


Jack Jenn from Living in hope on planet earth. on February 06, 2020:

Hi Angela,

An interesting article and even more interesting comments.

So I'll throw one more into the mix.

In fact, the answer has already been alluded to in a couple of the comments - and the true answer is in the very first book of the Bible, Genesis. More specifically verses 1 and 2. And this is the first mystery in the Bible.

Verse 1: In the beginning God created the heaven and the earth. This sentence can be either considered as a statement or a summary but it doesn't say when or how He did it, we simply know He did it from nothing and it was perfect.

Verse 2: And the earth was without form, and void; and darkness was on the face of the deep. These two verses contain the story of the ORIGINAL creation while the verses after record the story of God's full RE-creation of the earth over 6 literal days. And the original creation certainly was beautiful.

But verse 2 is suggesting the earth was a desolate place and in darkness at that time. So what can we deduct from that.

God told Adam and Noah to be fruitful, and multily, and replenish the earth. Replenish is another word for re-populate and meaning the same thing. If God didn't mean that He would have said to multiply and fill the earth, as if He was saying it for the first time. Both Adam and Noah were told to re-populate the earth after a major catastrophic flood on two occaisions. Which in fact, were separated by about 1100 years.

So now we have to consider that there was a considerable gap of time between verses1 and 2, which is now referred to as the 'Genesis Gap' and a Scotish theologian, Thomas Chalmers preached about it in the 19th century. But he wasn't the first to do so.

Peter, an apostle of Jesus, being led by the Spirit says in his Epistles,

2nd Peter 3: 5 - 7, For this they are willingly ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water: Whereby the world that then was, being overflowed with water, perished: But the heavens and the earth, which are now, by the same word are kept in store, reserved unto fire against the day of judgement and perdition of ungodly men.

I think that just about says it all doesn't it.

The newly constructed earth that Adam walked on was absolutely pristine on the surface. But under Adam's feet and hidden in the rocks are the burried fossils/remains, which we have now discovered and is God's record of the truth of the existence of a previously created original earth.

My best regards Angela,


Zia Uddin from UK on October 22, 2018:

Certainly looking forward to reading about that one. All the best.

Patty Inglish MS from USA and Asgardia, the First Space Nation on October 22, 2018:

Hi Angela - The rhinoceros makes me wonder if the Triceratops was actually a mammal; and, if a giant crocodile or Komodo Dragon is not a "small" dinosaur, I'd be surprised. Some scientists believe that dinosaurs became small instead of extinct. Fun to think about.

Angela Michelle Schultz (author) from United States on October 22, 2018:

I actually personally believe that dinosaurs and humans both lived on the earth at the same time. I will have to write an article about that sometime.

Zia Uddin from UK on October 21, 2018:

Nice written hub. I loved dinosaurs when I was a kid and i still do. It's sad they're gone. It's either the Chicxulub asteroid that wiped them out or the parting of the seas and land as you've mentioned.

Maybe the dinosaurs were meant to go so humans can inhabit the earth next. What next after humans I wonder?

Angela Michelle Schultz (author) from United States on February 06, 2017:

I am curious why you believe that humans and dinosaurs never co-existed?

Sylvia from Styles on February 04, 2017:

Very interning article. I believe that humans were forthcoming so inevitably the idea of dinosaurs and humans would not work. But that did not cause their extinction, I believe it was a combination of events.

Monk E Mind from My Tree House on September 25, 2012:

There is a rational explanation for why the dinos went extinct.

All species die from either background extinction or mass extinction. The dinosaurs died from mass extinction due to the inversion of the ecological pyramid.

Angela Michelle Schultz (author) from United States on May 10, 2012:

Thank you so much!

Dubuquedogtrainer from Dubuque, Iowa on May 09, 2012:

Well written and interesting. Voted up!

Angela Michelle Schultz (author) from United States on May 08, 2012:

I appreciate it quite well, I like how everyone is adding to the research I did.

Patty Inglish MS from USA and Asgardia, the First Space Nation on May 08, 2012:

Very very interesting comments, are they not? This is a pretty good discussion thread.

Angela Michelle Schultz (author) from United States on May 08, 2012:

You always give such insightful comments hirundine. Thank you for adding to my article.

hirundine from Nelson, B.C. Canada on May 08, 2012:

I'm generally in agreement with Patty Inglish, MS. You make a lot of sense. Though like angela_michelle, just being an interested party; I seldom see any other types of dating done that is not radiocarbon. Though that does not diminish the interest.

Uwe George, a scientist, in his book; "In the deserts of this world" ..... I think? Anyway, part of the thrust of his argument was that. Earth is an an aberration in nature. That true nature is desert. Once Earth becomes desert, it takes a very long time to change back? If ever? That homo sapiens, human beings. Are nature's way of achieving that goal, desert, on this planet? ....... Bit of a stretch? I agree!

Yet, over the 30 years since learning of his idea, it is becoming actually quite valid, when one looks at the people run amok with greed. Using what the planet has put here and then claiming it as "theirs". Doing all manner of despicable action; to hold on to that stuff, selling and doling it out for profit until they die. A lot of people are comfortable with that and there are more and more people; wanting some. So, I kinda' see where Uwe was coming from ....

Angela Michelle Schultz (author) from United States on May 08, 2012:

Thanks for stopping by Gloshei. I appreciate your comment.

Angela Michelle Schultz (author) from United States on May 08, 2012:

Patty, I actually often question the radiocarbon dating, but I have not found any evidence of any other timing.

Angela Michelle Schultz (author) from United States on May 08, 2012:

rahul thank you for the great compliment.

It does appear that there is evidence of something causing volcanic activity and something caused the land to really split, but I don't know if we will ever really know.

Gloria from France on May 08, 2012:

Thanks for that angela my excuse is it's an age thing! (with me)

Keep up the interesting hubs.

Patty Inglish MS from USA and Asgardia, the First Space Nation on May 07, 2012:

Since radiocarbon dating is reliable only to 40,000 - 60,000 years to the past, I discount the asteroid impact being 16.5 million yrs past as a statistical fallacy; and, our colleges and universities here are teaching other theories of extinction. The proliferation of the asteroid was pushed by money and politics. As Big 10 and other US and International schools begin to overturn the asteroid idea, I believe they have more accurate information. Their research scientists are some of the best in the world.

Our scientists here may not think the thunder lizards became smaller, but have an idea that dinos consumed all/most of their resources and this is esteemable, because when a planet loses its vegetation (consumed), it begins to lose its atmosphere and finally becomes an ice ball. That's happening right now to Earth. It gets warmer, resources get used up, it gets warmer, atmosphere escapes, then its gets very cold.

Jessee R from Gurgaon, India on May 07, 2012:

A great Write Angela! (love your name :))

I have always stood by the Meteor theory 'cause that sounds the most practical to me! We see a certain change in evolutionary mechanism after the Jurassic Age which tends towards the theory of a major catastrophe rendering a change in the mechanism of evolution. When questions like these arise, The Meteor and its dust causing immediate cooling or sudden eradication of the Dinosaurs seem explainable!

A wonderful article.. loved it!

Angela Michelle Schultz (author) from United States on May 07, 2012:

I actually didn't even run across the algae theory. Interesting. I did run across suggestions of Dino farting, but ignored that as just humorous. LOL. Thank you for your insights.

Patty Inglish MS from USA and Asgardia, the First Space Nation on May 07, 2012:

I enjoyed reading this Hub, because of the number of theories reviewed. Another taught in some College classes is one of accumulating algae in the oceans and seas, even more than we currently have. At the same time, two sides of argument look at the algae causing and preventing an ice age by absorbing either warmth or Co2.

A blurb on the Internet recently supported the greenhouse gases theory with a mention "Dino farting", like the cows and pigs producing too much methane today...and we have so many people doing the same.

I think the theory I like best is a newer one, in which some dinosaurs did not go extinct, but became progressively smaller because of lack of resources to keep them big. Hence, our giant variety of crocs and many other lizards of today.

The asteroid theory was quite popular for awhile, but is waning in my area.

Cloning may remotely have a chance to work short-term -- Dolly the Sheep that was cloned didn't live the usual lifespan; and probably the 1st or 2nd progeny might be extinct if I recall from genetics classes not sure. More prone to cancer, though.Anyway, all interesting.

Thanks for he Hub and I rated it Up and several more.

Angela Michelle Schultz (author) from United States on May 07, 2012:

hirundine, I can understand both perspectives, but honestly, I am not completely for cloning. I have a lot of reservations when it comes to cloning as well.

Angela Michelle Schultz (author) from United States on May 07, 2012:

Deancash, So far they have not been able to clone anything and have it survive into adulthood, so I'm not so sure how long that will be from now.

Angela Michelle Schultz (author) from United States on May 07, 2012:

Gloshei, actually the ice age is when the mammoth and the saber tooth cat became extinct. The dinosaurs became extinct prior to this. I am a geek and know these things. :)

hirundine from Nelson, B.C. Canada on May 07, 2012:

Dear DeanCash,

I find it quite interesting that you voice your support for "cloning". That some human beings think that everything and everyone; is here for our use in some bizarre fashion? Including other life forms. This, I find baffling?

Do you think you have an environment even suitable, to support this? Not everything has to be reduced to test-tube values. Respect for the other life-forms; that share our environment, needs to be valued. When dead monsters, from earth's past require more funding than those hungry now. Just because "you can" it should not be prelude to "do".

What's there to understand? It is the "now" we need to understand. .... Cheers!

DeanCash on May 07, 2012:

This is very interesting. But looking to the future I think it might be possible too, to clone what it was from past so we could better understand them.

Gloria from France on May 07, 2012:

This is a great hub and interesting, we all have heard different theories and still not sure.

I always thought it was the ice age but now I am not so sure.

One thing I am glad they are not still around. Thanks again for a good hub.

Angela Michelle Schultz (author) from United States on May 07, 2012:

I wish we had hard core facts, so we knew exactly what is gone and the true impact of all decisions made.

hirundine from Nelson, B.C. Canada on May 07, 2012:

While in general, I agree with the meteor impact theory? Likely there was not, one event?

Given the nature of today's globe it was a creeping change over a few thousand years. As the planet became colder and more like today's weather patterns. That's just my personal gut feeling? After all it took a few million years to change?

What I find surprising is the amount of time expended on the past and we leave our future up to those industrialists; that would turn this planet into another desert. The crude oil of today, is a legacy of those days; of dinosaurs and of the planet's development.

Apparently it all belongs to corporations! All owned by one family. Now how does that work? ...... Cheers!

Angela Michelle Schultz (author) from United States on May 07, 2012:

Vegas Elias,

That was one of the many theories, but I didn't feel there was enough scientific evidence to include it on my list. there were a lot of other ones as well, I didn't include for much the same reason.

Angela Michelle Schultz (author) from United States on May 07, 2012:

I'm glad you enjoyed it, wewillmake!

Vegas Elias from Mumbai on May 07, 2012:

Predators including prehistoric ancestors of man also might have contributed to the extinction of the dinosaurs by killing them for food after trapping them in trenches. Of course I also agree with the other reasons given in this article.

wewillmake from kerala-INDIA on May 06, 2012:

Nice article... I love the research articles very much.. Very informative..

Angela Michelle Schultz (author) from United States on May 06, 2012:

Thank you so much!

Sheila Brown from Southern Oklahoma on May 06, 2012:

Very interesting hub. I have always wondered what could have occurred to cause so many animals to die at the same time. There are some very good, well explained theories here. Voted up and interesting! Have a great day! :)

Angela Michelle Schultz (author) from United States on May 06, 2012:

Thank you so much!

Angela Michelle Schultz (author) from United States on May 06, 2012:

Thank you very much for the nice comment.

chrissieklinger from Pennsylvania on May 06, 2012:

Interesting hub and a good read for someone just interested in the topic, or someone doing a project for school....great job!

BethDW on May 06, 2012:

Such an interesting managed to summarize all the different theories really nicely. I also like that you provided citations (so many authors of more 'scientific' hubs often don't, and it lends your writing a lot more credibility). Voted up and shared!

Angela Michelle Schultz (author) from United States on May 06, 2012:

teaches12345, thank you very much. I find dinosaurs so fascinating.

Angela Michelle Schultz (author) from United States on May 06, 2012:

thelyricwriter, It is actually quite amazing if you think about it. Not all dinosaurs fossilized, so there are actually dinosaurs that we will never know about, because none of them managed to fossilize.

Angela Michelle Schultz (author) from United States on May 06, 2012:

JKenny, Thank you very much. There are actually even more theories than I listed, but these were the ones I felt made the most sense.

Dianna Mendez on May 06, 2012:

This question is one that may never be answered in our lifetime, but your research and coverage holds some valid concepts. Great science lesson on these creatures.

Richard Ricky Hale from West Virginia on May 06, 2012:

Voted up, useful, and interesting. I have always liked dinosaurs. It is interesting that we can learn so much from their 65 million year old bones. Scientist have did a great job putting the puzzle together. Cool article.

James Kenny from Birmingham, England on May 06, 2012:

I've always subscribed to the meteor impact theory, but your hub makes it clear in a very good and balanced way, that there are still many unanswered questions. Great work. Voted up and shared.

Related Articles