Catastrophic Failure Of Earth's Global Systems Led To The Extinction Of The Dinosaurs – We May Yet Go The Same Way

TThe Extinction Of The Dinosaurs – We May Yet Go The Same Way iurii/Shutterstock

“Why did the dinosaurs die out?” The consensus, among palaeontologists and dinosaur crazy seven-year-olds alike, seems to be that about 66m years ago a 10km diameter asteroid crashed into what is now Central America. It raised up a cloud of dust and ash that spread across the upper atmosphere, blocking out the sun, cooling the Earth and destroying the ozone layer that protects life from harmful cosmic radiation.

These effects lasted more than a decade, devastating Earth’s plants and plankton. The devastation rapidly travelled up food chains, first killing off the large herbivores, who were unable to find enough food, and then the carnivores, who soon found themselves in the same position. A staggering 75% of species, including all “non-avian” dinosaurs, died out. This event, known as the end-Cretaceous mass extinction, is one of the “big five” such extinctions known from the past 500m years of Earth’s history.

climate PENDING PERMISSION. Sam Noble Museum, Oklahoma University

But this was not the only dramatic event to coincide with the death of the dinosaurs. At around the same time, in central India, a truly colossal series of volcanoes were spewing out over a million cubic kilometres of lava together with sulphur and carbon dioxide that changed the climate and caused global acid rain. Meanwhile, a slowing of undersea tectonic activity led to one of the most rapid periods of falling sea levels in the history of the planet, devastating coastal ecosystems.

This has led to some pretty heated debates about what “really” killed the dinosaurs, especially as there have been times when similarly dramatic events occurred without seeming to cause nearly so much harm.

climate One of the ‘big five’ extinctions. AuntSpray/Shutterstock

Perhaps this is the wrong question to ask.

Profound, complex, interconnected change

Growing evidence now suggests that these events were interconnected and that the dinosaurs’ extinction cannot be explained as a simple process during which one “bad thing” fell out of a clear blue sky and everything died. Rather, it involved profound, complex and interconnected changes to the global systems that support life.

For instance, the late cretaceous period saw gradual and subtle restructuring of terrestrial ecosystems, making them more vulnerable to catastrophic collapse. Such restructuring was potentially brought about by multiple evolutionary and ecological changes related to climate change, the increasing dominance of flowering plants, and fluctuations in the diversity and abundance of particular dinosaur groups.

Nor is this complexity an unusual feature of mass extinctions. Across all five of Earth’s devastating global catastrophes, there is a veritable whodunit of possible causes. These include asteroids, volcanoes, climate change (both warming and cooling), the evolution of new species such as deep-rooted plants that turned bare rock into rich soil for the first time, and even the effects of nearby exploding stars.

Yet, the biggest of all mass extinction events, the “Great Dying” at the end of the Permian period 250m years ago – which killed 90% of all species on Earth – looks even more complex. No fewer than seven potentially catastrophic events are associated with this period in geological history. These include the evolution of new strains of microorganism, an asteroid impact, and a humongous area of volcanic activity in present day Siberia that erupted for a million years.

But the greatest changes may have taken place in the Earth’s oceans. There were large-scale emissions of methane from the ocean floor,the stagnation of ocean currents, increased levels of sulphur dioxide causing phytoplankton death, and declining levels of oxygen.

With so much going on, it is less surprising that 90% of all species died out than that 10% survived.

Precarious times

What does this imply about our current age, which many now see as constituting a “sixth” mass extinction11? At the Centre for the Study of Existential Risk at Cambridge University, we often come up against the problem of today’s “unprecedented” global threats. Some of these, like the threats from nuclear weapons or Artificial Intelligence, may seem akin to asteroids falling out of the sky, and we are often asked which most worry us. One thing we can take away from the study of previous mass extinctions is that this question may be misplaced.

Humanity lives far more precariously than we think, dependent upon a great many global systems, from the environment that provides us with food, water, clean air and energy to the global economy that supplies goods and services where we want them and when we want them, often on a “just in time” basis.

From looking at the historical, and the geological, record it becomes clear that such systems can easily pass through phase changes in which a previously stable system quickly, and sometimes irrevocably, changes into a chaotic one. Scientists have already identified how this might occur in relation to phenomena such as climatic tipping points (where climate change becomes self-sustaining, rather than being simply “man-made”), ecosystem collapse (where the loss of a few key species can cause whole ecosystems to disappear), and hyperinflation (where previously stable economic institutions cease functioning and money loses its value).

climate Climatic tipping point? Roschetzky Photography/Shutterstock

Another thing that we learn from these past events is that there is no law of nature that prevents such phase changes becoming global in scope or catastrophic in nature. If pushed far enough, global systems can evidently collapse into a death-spiral, whereby the damage to one species, ecosystem or environmental process causes problems for others, creating positive feedback that accelerates change and makes it self-sustaining.

Indeed, while the popular “Gaia hypothesis” suggests that global systems act to promote the overall stability of our planet, there is no conclusive evidence that the biosphere adjusts to changes to support the continuation of complex life. Indeed, it was recently suggested that one reason life may be rare on other planets is that its emergence often pushes planetary systems away from the conditions necessary for its continued existence. It is not impossible that this could still happen on Earth.

climate Profound change. FloridaStock/Shutterstock

Nor may the systems we ourselves have designed be any less fragile in this respect. Indeed, many of our institutions have shown themselves to be almost entirely unconcerned with human well-being; so long as they can serve the interests of short-term profit maximisation, voter turnout and other, ultimately useless, goals.

Yet, it might not be all bad news for humanity. Some theorists suggest that the catastrophic effects of a mass extinction tend to sweep away the highly adapted specialists of the era, and allow more flexible generalists to survive and eventually flourish into new forms. So perhaps we can take comfort from the fact that humans have showed themselves to be the ultimate generalists, adapting to survive, though not always thrive, in every habitat on Earth, and even in outer space.

But we should also reflect on the fact that most of this flexibility flows not from our biology but from the technologies we have created. Not only are these the very technologies that are leading us to push global systems as far as we have, but they are rapidly passing out of the realms of human comprehension in their complexity and sophistication. Indeed, it now requires immense individual knowledge to use and maintain them, making each of us, individually, just the sort of adapted specialists most vulnerable in a mass extinction event – something that may not be quite such good news after all.The Conversation

About The Author

Simon Beard, Senior Research Associate, Centre for the Study of Existential Risk, University of Cambridge; Lauren Holt, Research Associate, Centre for the Study of Existential Risk, University of Cambridge, and Paul Upchurch, Professor of Palaeobiology, UCL

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Related Books

Climate Change: What Everyone Needs to Know

by Joseph Romm
0190866101The essential primer on what will be the defining issue of our time, Climate Change: What Everyone Needs to Know® is a clear-eyed overview of the science, conflicts, and implications of our warming planet. From Joseph Romm, Chief Science Advisor for National Geographic's Years of Living Dangerously series and one of Rolling Stone's "100 people who are changing America," Climate Change offers user-friendly, scientifically rigorous answers to the most difficult (and commonly politicized) questions surrounding what climatologist Lonnie Thompson has deemed "a clear and present danger to civilization.". Available On Amazon

Climate Change: The Science of Global Warming and Our Energy Future second edition Edition

by Jason Smerdon
0231172834This second edition of Climate Change is an accessible and comprehensive guide to the science behind global warming. Exquisitely illustrated, the text is geared toward students at a variety of levels. Edmond A. Mathez and Jason E. Smerdon provide a broad, informative introduction to the science that underlies our understanding of the climate system and the effects of human activity on the warming of our planet.Mathez and Smerdon describe the roles that the atmosphere and ocean play in our climate, introduce the concept of radiation balance, and explain climate changes that occurred in the past. They also detail the human activities that influence the climate, such as greenhouse gas and aerosol emissions and deforestation, as well as the effects of natural phenomena.  Available On Amazon

The Science of Climate Change: A Hands-On Course

by Blair Lee, Alina Bachmann
194747300XThe Science of Climate Change: A Hands-On Course uses text and eighteen hands-on activities to explain and teach the science of global warming and climate change, how humans are responsible, and what can be done to slow or stop the rate of global warming and climate change. This book is a complete, comprehensive guide to an essential environmental topic. Subjects covered in this book include: how molecules transfer energy from the sun to warm the atmosphere, greenhouse gases, the greenhouse effect, global warming, the Industrial Revolution, the combustion reaction, feedback loops, the relationship between weather and climate, climate change, carbon sinks, extinction, carbon footprint, recycling, and alternative energy. Available On Amazon

From The Publisher:
Purchases on Amazon go to defray the cost of bringing you InnerSelf.comelf.com, MightyNatural.com, and ClimateImpactNews.com at no cost and without advertisers that track your browsing habits. Even if you click on a link but don't buy these selected products, anything else you buy in that same visit on Amazon pays us a small commission. There is no additional cost to you, so please contribute to the effort. You can also use this link to use to Amazon at any time so you can help support our efforts.

 

enafarzh-CNzh-TWdanltlfifrdeiwhihuiditjakomsnofaplptruesswsvthtrukurvi

follow InnerSelf on

facebook icontwitter iconyoutube iconinstagram iconpintrest iconrss icon

 Get The Latest By Email

Weekly Magazine Daily Inspiration

EVIDENCE

hurricanes and ocean warming 6 20
Hurricanes Are Boosting Long-term Ocean Warming, New Research Shows
by Noel Gutiérrez Brizuela and Sally Warner
When a hurricane hits land, the destruction can be visible for years or even decades. Less obvious, but also powerful,…
smoke stacks 5 12
Climate Change First Went Viral Exactly 70 Years Ago
by Marc Hudson, University of Sussex
We have grown so used to many things. To the pictures of wildfires and cremated animals, to the ice sheets calving into…
will you reconize 5 8
The Dangers of Crossing Tipping Points
by InnerSelf Staff
The planet is currently facing a grave threat due to climate change. Global warming is causing environmental changes…
Record Low Antarctic Sea Ice Is Another Alarming Sign
by Craig Stevens, National Institute of Water and Atmospheric Research
A changing climate is upon us, with more frequent land and marine heatwaves, forest fires, atmospheric rivers and…
Here’s Why Ocean Temperatures Are The Hottest On Record
by Moninya Roughan, UNSW Sydney
Large swathes of the world’s oceans are warm. Unusually warm. The heat this year is likely to break records. Since…
Blue water surrounded by dead white grass
Map tracks 30 years of extreme snowmelt across US
by Mikayla Mace-Arizona
A new map of extreme snowmelt events over the last 30 years clarifies the processes that drive rapid melting.
White sea ice in blue water with the sun setting reflected in the water
Earth’s frozen areas are shrinking 33K square miles a year
by Texas A&M University
The Earth’s cryosphere is shrinking by 33,000 square miles (87,000 square kilometers) per year.
Why Human Fingerprints On Our Climate Are Not An Isolated Phenomenon
Why Human Fingerprints On Our Climate Are Not An Isolated Phenomenon
by Alex Smith
The fact that humans contribute to the warming of our planet is nothing new. Scientists have been telling us about the…

LATEST VIDEOS

can we cool the planet 7 22
Can We Cool The Planet?
by Robert Jennings, InnerSelf.com
Climate change has emerged as one of the most pressing challenges of our time. Over the past century, human activities…
i5w7rk3a
The Devastating Impact of 3C Global Warming
by Robert Jennings, InnerSelf.com
Global warming is a pressing issue that poses severe threats to our planet and all its inhabitants. In recent years,…
The Great Climate Migration Has Begun
The Great Climate Migration Has Begun
by Super User
The climate crisis is forcing thousands around the world to flee as their homes become increasingly uninhabitable.
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
The Last Ice Age Tells Us Why We Need To Care About A 2℃ Change In Temperature
by Alan N Williams, et al
The latest report from the Intergovernmental Panel on Climate Change (IPCC) states that without a substantial decrease…
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
The Caspian Sea Is Set To Fall By 9 Metres Or More This Century
by Frank Wesselingh and Matteo Lattuada
Imagine you are on the coast, looking out to sea. In front of you lies 100 metres of barren sand that looks like a…
Five Climate Disbeliefs: A Crash Course In Climate Misinformation
The Five Climate Disbeliefs: A Crash Course In Climate Misinformation
by John Cook
This video is a crash course in climate misinformation, summarizing the key arguments used to cast doubt on the reality…
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
The Arctic Hasn't Been This Warm For 3 Million Years and That Means Big Changes For The Planet
by Julie Brigham-Grette and Steve Petsch
Every year, sea ice cover in the Arctic Ocean shrinks to a low point in mid-September. This year it measures just 1.44…
What Is A Hurricane Storm Surge and Why Is It So Dangerous?
What Is A Hurricane Storm Surge and Why Is It So Dangerous?
by Anthony C. Didlake Jr
As Hurricane Sally headed for the northern Gulf Coast on Tuesday, September 15, 2020, forecasters warned of a…

LATEST ARTICLES

global boiling is here 7 29
U.N. Warns: The Era of Global Boiling Has Arrived
by Robert Jennings, InnerSelf.com
The world faces an unprecedented climate crisis as temperatures soar and heat records are shattered across the globe.
amoc map 7 26
The Unseen Tipping Point: Understanding the Potential Impact of an AMOC Shutdown
by Robert Jennings, InnerSelf.com
The Unseen Tipping Point: Understanding the Potential Impact of an AMOC Shutdown Have you ever heard of the Atlantic…
can we cool the planet 7 22
Can We Cool The Planet?
by Robert Jennings, InnerSelf.com
Climate change has emerged as one of the most pressing challenges of our time. Over the past century, human activities…
global hungry 7 22
The Rising Tide of Global Hunger: Pandemic, Climate & Conflict Fuel Food Insecurity
by Robert Jennings, InnerSelf.com
In recent years, the world has witnessed a distressing surge in global hunger, painting a bleak picture of food…
keeping cool 7 20
Beat the Heat: Your Guide to Staying Safe in Extreme Temperatures
by Robert Jennings, InnerSelf.com
As the temperatures rise during the summer months, it's important to be aware of the risks associated with extreme heat.
i5w7rk3a
The Devastating Impact of 3C Global Warming
by Robert Jennings, InnerSelf.com
Global warming is a pressing issue that poses severe threats to our planet and all its inhabitants. In recent years,…
how hot is too hot 7 19
How Hot is Too Hot? The Risks of Extreme Heat on the Human Body
by W. Larry Kenney, Penn State et al
The answer goes beyond the temperature you see on the thermometer. It’s also about humidity. Our research is designed…
european heatwave 7 18
European Heatwave: What’s Causing It And Is Climate Change To Blame?
by Emma Hill and Ben Vivian, Coventry University
Europe is currently in the midst of a heatwave. Italy, in particular, is expected to face blistering heat, with…

The El Niño Southern Oscillation, is a powerful climate cycle that affects almost every part of the world. El Niño and La Niña are two phases of this cycle that originate in the Pacific Ocean but...

A new report from the National Academies of Sciences, Engineering and Medicine tackles a controversial question: Is solar geoengineering – an approach designed to cool the Earth by reflecting...

Our society asks so much of these fragile ecosystems, which control freshwater availability for millions of people and are home to two thirds of the planet’s terrestrial biodiversity.

For any country blessed with easy access to the shallow and windy North Sea, offshore wind will be key to meeting net zero targets.

Fire is a hot topic these days, particularly when it comes to the boreal forest, the vast expanse of trees that stretches across Alaska, Canada and other cold northern regions.

Here’s something fascinating about stories that recount a major change of heart.


 Get The Latest By Email

Weekly Magazine Daily Inspiration

New Attitudes - New Possibilities

InnerSelf.comClimateImpactNews.com | InnerPower.net
MightyNatural.com | WholisticPolitics.com | InnerSelf Market
Copyright ©1985 - 2021 InnerSelf Publications. All Rights Reserved.