Introduction
5 is how many fingers you have.
5 is how many senses you have.
5 is how many large scale mass extinctions we've had.
In this article I had the privilege of interviewing Professor Mike Benton from the University of Bristol who is a Professor of Vertebrate Palaeontology , specialising in the large scale evolution of some famous groups such as the dinosaurs and how environmental changes such as mass extinctions influenced the biodiversity of birds, reptiles and mammals. He has written over 50 books and 400 academic research papers (do give them a read!).
To see the key questions from the interview watch the videos below!
The 'Big Five' as they are often called represent 5 pivotal moments in our history that we should all really be familiar with (but we aren't so here we are).
Ordovician-Silurian (400 Million years ago (Mya))
Devonian (365 Mya)
Permian-Triassic (250 Mya)
Triassic-Jurassic (210 Mya)
Cretaceous-Tertiary (65 Mya)
"But Aryan, why am I reading about things that died in the past when I'm living in the present?"
Well fellow human, it is because I think we can all take some pointers from our predecessors in their and our very own struggle for survival here on Earth and see what we can do to prepare ourselves or reduce the impacts of a very imminent Sixth Mass Extinction.
Story time
If you want to start analysing the history of mass extinctions on Earth, I think it's best to look at the worst one, the Permian-Triassic Extinction (PTME) 250 million years ago. In this event approximately 96% of marine species and 75% of terrestrial species became extinct.
One main killer in the PTME was the eruption of a Large Igneous Provinces (LIP) in Russia and China which inevitably released an immense volume of CO2 and So2 too, which if you were unaware are some of the most potent greenhouse gases known to man.
So you can see that it was the greenhouse gases that killed the majority of life on Earth at that time.
These are the old threats that are causing the new worries for us
According to Bill Gates, we subject this planet to 50 billion tonnes of CO2 being released into the atmosphere every year. It may not be from a volcano, but it is still Carbon Dioxide being emitted, but at a more accelerated rate. I don't think you or even I could begin to imagine the impacts of this. But to help you realise the scale of this...
Let me introduce you to Professor Mike Benton.
Questions we need to answer
In my discussion with Prof. Benton, we addressed some key questions that I feel are not at the tip of people's tongues. Let's go through them, shall we?
What are very real threats that we are experiencing today or will experience in the near future - threats that were previously thought not to have been as imminent as they are?
Some of these threats (sea level rise, temperature rise and acidification) are known to most when they think about 'Climate change' or 'Global Warming', but when you compare this to previous Mass Extinctions, we look really bad in this light.
Prof. Benton says that whilst these events did occur in the past, there was no 'people pressure' or 'overpopulation', indicating that our very existence and demand for 'stuff', the need to travel everywhere on an aeroplane is unjustified and accelerating our descent into a Sixth ME (Mass Extinction), making primitive threats more real than they have ever been.
2. What impact would ocean anoxia have had on the small number of vertebrates and invertebrates that began their transition onto land at the end of the Devonian?
Whilst the Devonian period (419 million years ago) is unheard of to most of you, it marks the 'age of fish', seeing the transition of our predecessors from water onto land, from fish to tetrapods. Ocean anoxia is a very real threat and was certainly radiated throughout the planet in the Devonian, which caused the demise of so many taxa, but whilst it was a global and large scale event that occurred, it was mainly the fish such as Dunkleosteus that felt the immediate impacts, whereas the first land colonising plants that continually adjusted themselves for 50 million years to a new ecosystem managed to escape and thrive despite the Ocean Anoxic event.
Maybe this alludes to impacts of Anoxia in the future? Terrestrial species are at lower risk of it but marine life takes the biggest hit, impacting us indirectly at a later stage.
3. How much more is there really to find out about Mass Extinctions?
Prof. Benton argues that with the current age of technological advancement and from what we know about previous ME's, we can learn and comprehend more than ever about them. Whilst we cannot yet experimentally test ME's on any population due to the ethical concerns posed, fine tuning and honing in on the details about how different elements of them relate to various fields such as vulcanology and meteorology can help us to understand even more than we do today.
4. In the Permian-Triassic Extinction, this was caused primarily by LIP's (large igneous provinces), what is the chance of one erupting in the very near future?
Large Igneous Provinces (LIP's) are accumulations of igneous rock formed when magma peaks through the crust and onto the surface, usually above tectonic hotspots. The eruption of them was the leading cause of the 9/10 species extinction in the PTME (Permian-Triassic). But, thankfully you can wipe that sweat off your forehead because they don't erupt periodically and we aren't exactly sure when they are next due to.
I think it is unlikely one will erupt in your lifetime, but
I do believe that when it does happen, it will wreak havoc and cause more death than it has done in the past.
for reasons such as the ongoing environmental and ecosystem degradation, preventing our world from tolerating such an event as well as it did 252 million years ago.
5. Do you think with the increase in industrial activity and the rate at which we are going, there will be sufficient time for us to adapt physiologically to such changes in conditions?
We can estimate that it takes other species around 0.5 to 1 million years to recover from a hyperthermal (geological period of global warming) ME. There is only so much a human can adapt to Earth's harsh conditions, because unlike the tardigrades (as mentioned two articles ago), we have a narrow comfort zone of adaptation and have no where to hide when things get tough.
Professor Benton suggests that it is unlikely we are one of those species to recover after a hyperthermal event, so the only thing we can do instead of hypothesising our chance of recovery, is to figure out a way to reduce global temperature to a stable one.
6. Apart from what is already being done to combat elements of ME's such as climate change, is there an element or part of fighting a ME where you think not enough is being done?
Despite all of the doom and gloom of ME's, one good thing is the fact that we are more aware than ever about what needs to be done and what is affecting our planet as we speak, however Professor Benton argues that elements such as resource exploitation is something we take for granted and should pay more attention to.
In addition,
the very basis and infrastructure of our livelihoods and societies could do with a reboot and need to change now.
I imply that everyday we negatively impact Earth and contribute to an extinction whether we like it or not - travelling in the car, buying a smartphone, using that extra bit of plastic.
Maybe a look at our ancestors and hunter-gatherer societies as Dr. Christopher Ryan suggests in his book 'Civilised to Death' is needed to understand the scale of destruction occurring right under our noses?
7. What does technology have to do with it and possible future solutions?
As humans, it is quite tempting to, but we cannot solely rely on the use of technology to get us out of this mess we have got ourselves in. Many people such as Bill Gates are tackling this issue and trying to implement this use into our everyday lives, but surely in order to effect change that drive must come from within yourself?
No amount of technology can change the world if there is no intent present.
The Maths Doesn't lie
One thing I think you will find interesting are the causes of mass extinctions. Now I know I said there were 5 mass extinctions, but in reality in the last 600 Million years, there have been 12 smaller scale (but still pretty big) extinction events.
This puts the total at 17 events, of which 4 were caused by asteroids smashing up the place. This means that a grand total of 13 mass extinctions were Earth induced, meaning they were caused directly by climate change. Nothing extra-planetary involved here.
So when the Sixth Mass Extinction event comes in the near future, it is more likely to have been our fault than something floating through space such as an asteroid.
The maths doesn't lie.
Conclusion
So, as you can see from my interview with Professor Benton, there's a lot of work that needs to be done, but we already knew that. What we discussed here provides a deeper insight into what previous mass extinctions such as the Permian-Triassic (PTME) can teach us about fighting Mass Extinction today, such as perhaps changing the dynamics of society to suit the planet, or focusing our attention on other key but not as popular threats?
One thing that should be kept in mind is always looking back at what Earth has to offer us so we can learn the lesson here and prevent 9/10 species from dying out once again.
Remember, 13/17 extinction events were Earth induced, so let that sink in and help you make the right decisions about how you want to save your species from extinction.
If you want to watch the interview in its entirety, please click here to see it on my Youtube channel, the 'EarthSci Show', where I plan to do more interviews and podcast episodes in the future!
Bibliography
Hyperthermal-driven mass extinctions: killing models during the Permian–Triassic mass extinction - Professor Mike Benton - https://cpb-eu-w2.wpmucdn.com/blogs.bristol.ac.uk/dist/5/537/files/2021/01/2018hyperthermals.pdf - accessed 24/2/21
Mass Extinctions and the future of life on Earth - Prof. Mike Benton - https://www.ted.com/talks/michael_benton_mass_extinctions_and_the_future_of_life_on_earth - date accessed 28/3/21
The role of extinction in evolution - David Raup - https://www.pnas.org/content/pnas/91/15/6758.full.pdf - date accessed 30/2/21
Large Igneous Provinces - https://en.wikipedia.org/wiki/Large_igneous_province - date accessed 6/3/21
Bill Gates and Rashida Jones Ask Big Questions (Podcast) - https://www.gatesnotes.com/podcast - date accessed 19/1/21