Jessica Morrison: This is The Future Of, where experts share
their vision of the future and how their work is helping shape it for the better.
Jessica Morrison: I'm Jessica Morrison. Mass extinction events
are something we're taught about at a young age, from the knowledge that dinosaurs were
once the dominating species of life on this planet before they were all wiped out. But
it might surprise you to know that since the formation of life on earth, 541 million years
ago, that there have been five mass extinction events. With the undeniable impact that humans
are having on the planet, and plant and animal species, scientists are now asking the question:
are we in the middle of a sixth mass extinction event? I sat down with world-renowned, organic
geochemist and Australian Laureate fellow, Professor Kliti Grice, to discuss this topic
and more. Jessica Morrison:
First, we'll start with: what are we only now just learning about past mass extinction
events? Professor Kliti Grice:
Okay. I guess anyone who's heard of the extinction of the dinosaurs has known about at least
one of those events. The dinosaurs are the most notorious victims of a mass extinction
event, 66 million years ago, but even worse events have previously occurred, at least
four. For instance, the Great Dying, the largest of the five known mass extinction events,
occurred 252 million years ago, and was associated with Siberian volcanic eruptions, when this
massive supercontinent, Pangea, was formed. And likely contributed to the event, leading
to global warming of the planet, release of toxic gases and metals, ocean acidification,
depleted oxygen levels in the oceans, and it was probably a cascade of events that led
to the observed catastrophic event of the mass extinction event 252 million years ago.
So today, we do really worry about the current global warming and the COVID-19 pandemic has
probably brought to the fore in people's minds about how one event can impact the lives of
all people from all nations. Professor Kliti Grice:
And while, I guess, this pandemic is nowhere near a mass extinction event, it does link
up the idea of, I guess, a widespread global event that severely impacts life and ways
of life. Things like increasing frequency of forest fires, which Australia has experienced,
ocean acidification, expansion of oxygen minimum zones, degrading shorelines, melting ice caps,
increases in pollution, such as from phosphorus and nitrogen inputs. And now we're even having
plastic pollution in the oceans. And these are all points of serious concern today. So
I guess this is, you know, looking at the past, we've seen some of these changes that
have happened and we're also experiencing a lot of changes in our own environment today.
Jessica Morrison: You've recently been awarded a five-year research
project from the Australian Research Council to improve our understanding of past extinction
events and other evolutionary processes. Can you give an overview of that project and what
you're hoping to learn from it? Professor Kliti Grice:
Okay. So this is a Laureate project and it aims to unlock an untapped record of our planet's
past by analysing fossil material for new evidence of natural products in the form of
biochemicals or even their recognisable degradation products, which we call biomarkers or molecular
fossils. The well-studied inorganic fossil record has provided a framework for understanding
major events in the evolution of life and our planet. However, this project aims to
significantly advance current perceptions by assessing parallel, but rarer organic record
of ancient organisms, which are entombed and exceptionally preserved in concretion fossils.
Determination of the mechanics and controls of what is rapid, I guess, glue or biofilm
entrapment of these organic remains will contribute valuable new information about geobiological
functionality from an extension of the fossil biomarker record or a new way of interpreting
our planet's past with improved understanding of extinction, environmental change and adaptation.
Professor Kliti Grice: So we're going to have two parts of this project
put together. One is to look at the preserved uncontaminated fossils, including soft tissue
in these encapsulated concretions from different geological settings and timeframes by various
multidisciplinary analytical techniques to answer ecological, paleoenvironmental and
evolutionary questions of contemporary relevance. And the other part of the project is to perform
laboratory-controlled time experiments, which artificially grow concretion-enclosed fossils.
This is like basically making a fossil in the lab and this will be done with high school
students, so they can come and make their own fossils and see how the fossil is growing.
And we hope to identify the optimal growth conditions and establish the role of microbes
and the biofilms that they make in their formation. Jessica Morrison:
That is very cool. And what about, if there's any high school teachers listening who want
to get involved, how can they do that? Can they just reach out to you by email or something?
Professor Kliti Grice: Yeah, yeah. Yes, sure. We will have an outreach
coordinator in this project who can be contacted, but in the meantime, you're welcome to contact
me and we have various avenues of linking up with high school students through a number
of programs. Jessica Morrison:
That would be amazing, I would imagine. So we'll make sure we pop your details in the
shownotes so anyone can get in touch. How does the understanding of past extinction
events help us today and going into the future to sort of understand what's going on?
Professor Kliti Grice: Okay. I guess we really need to be able to
understand what happens before, during and after an extinction event in the past, so
that we can recognise the signs of trouble and consequences of the inaction. Also, we
can learn about the resilience of certain organisms and which lifeforms might compete
best under certain extreme conditions, so a bit of Darwinism at its acutest.
Jessica Morrison: So, based on your understanding of past events,
what's the likelihood of a naturally-occurring mass extinction event happening in our lifetime?
Professor Kliti Grice: Okay. That's an interesting question. Apart
from the end-Cretaceous asteroid that impacted the non-avian dinosaurs and other organisms,
the other four events were thousands or more year events. So, unless we're hit by an asteroid
or a comet, in advance, you would probably know if an asteroid was going to hit earth.
And we have no evidence this is imminent, I thankfully cannot see a mass extinction
event happening in our lifetime. If naturally-occurring means not caused by humans though, then I
guess about every 540 million years is possible and a chance of about one in one million within
a hundred-year lifetime, if that makes sense. Jessica Morrison:
Yeah. Okay. So it's not happening in the very near future, which is good for our listeners
to know. So, that's a good thing. Do you believe that we're in the middle of a human-induced
mass extinction event? Professor Kliti Grice:
No, but at worst, we're potentially at the very start of such a concerning human-induced
event, but certainly not significantly progressed on situation of mass proportions. And whether
or not it becomes one depends on environmental trends persisting over the next 100–1,000
years, I guess. However, we're at a very concerning early point, experience significant changes,
nonetheless, due to rapid and dramatic changes that are occurring to Earth's climate. Changing
the climate will impact species and humans or perhaps relative susceptible species. All
organisms will either die or adapt. Professor Kliti Grice:
Now, human extinction is the hypothetical end of the human species due to either natural
causes such as things like asteroid impacts, large-scale volcanism or anthropogenic, which
is human-induced, include things like climate change, global nuclear annihilation, biological
warfare and ecological collapse. There's a relative lower risk of near-term human extinction
due to natural causes. The likelihood of human extinction through our own activities, however,
is a current area of research and debate. I guess today's proposed extinction is very
different. It's an unnatural event and it has the magnitude of a mass extinction, but
this time it's not brought by a natural-occurring phenomenon, but is the direct result of an
activity of one individual species on all the rest.
Jessica Morrison: Is there any way to minimise the chances of
another mass extinction event from occurring? Professor Kliti Grice:
Interesting question. So, I guess we know from the geological record that the cause
of mass extinction events, whether it be a meteorite impact or massive volcanic eruptions
led to dramatic, rapid change to Earth's climate. While, I guess, we can not control large-scale
natural events to minimise the chances of a human-induced mass extinction event, we
need urgent climate action to mitigate the climate changes witnessed through the current
anthropogenic, human, epoch, which on a geological scale are progressing at a relative rapid
rate. Jessica Morrison:
Well, that leads me pretty well to my next question, Kliti. Extinction events seem like
such a bleak subject to want to research and talk about. Why do you find it so fascinating?
What inspired you to get into this field? Professor Kliti Grice:
I don't think it's bleak at all. I think it's actually very uplifting to know that even
under extreme stress, life actually finds a way and sure some species experience major
evolutionary events, which can be fatal, but what's nice is that new niches of organisms
flourish, leading to new more evolved forms and actually we humans wouldn't exist if we
did not have the dinosaur extinction. And I guess, as Charles Darwin quoted: "It's not
the strongest of the species that survives, nor the most intelligent, but rather the most
responsive to change." Jessica Morrison:
Positive outlook. What does it feel like to find a fossil as a researcher?
Professor Kliti Grice: A molecular fossil or a fossil? A molecular
fossil is the exciting part because you can't see it.
Jessica Morrison: Okay. Well, tell me about that. What is that
like? Professor Kliti Grice:
So, you know what a fossil is, like a remain, you might have seen in the museums a trilobite
or an ammonite– Jessica Morrison:
The little shell-looking– Professor Kliti Grice:
Yeah. Jessica Morrison:
Yes. Yeah, yeah. Professor Kliti Grice:
What we actually do is look at what molecules are within that, the molecular fossils. So
you can't actually see those, but they tell you a wealth of information about the organism,
what it is, what it might've eaten, what its ecosystem was like, how it was preserved,
what the environment was like. And we're talking about fossils, organisms that are extinct
today. So we might get a fossil which, an example of one is the Tully Monster, is an
organism that is called a 'bilateral', as its got two halves. And it's quite an interesting
organism because it's got an eyeball on its back and it's got a proboscis mouth. And it
was originally thought to be an invertebrate, but because it's got cartilage-type material
and it's got eyes and it's got teeth, then it's been reclassified as a vertebrate. So
we're actually looking at its diet, how it lived on the ocean floor. It's extinct, it
could be related to some of much earlier creatures on Earth from the Cambrian. So yeah, it's
really, really quite exciting to have something which is extinct and really pull it apart.
Jessica Morrison: Yeah, yeah.
Professor Kliti Grice: Yep.
Jessica Morrison: What's a future area in this topic that you
would love to research, Kliti? Professor Kliti Grice:
I guess, in Australia we'd like to really look at life's tipping points and resilience
of life throughout Earth's history by embracing and combining various disciplines, multidisciplines,
such as geology, geophysics, with biogeochemistry, genomics, Big Data and numerical modelling
to actually produce a revolutionary 4D framework that is in space and time as a foundation
for policies, practices and assessments of ecosystem resilience. We also don't know a
lot about the biodiversity of the deep ocean basins of today, let alone the diversity,
what it was like in the geological past. So yeah, we really want to address what is meant
by resilience of life on Earth, and actually learn from the past to help save and protect
our own environment and planet for the future. Jessica Morrison:
Fascinating. Fascinating. Thank you so much, Kliti, for sharing your knowledge on this
topic. And we really, really appreciate you coming in. Where can listeners go to find
out more about what you do? Professor Kliti Grice:
We have a website, the WA Organic Isotope Geochemistry Centre [ERROR: Facility] at Curtin
University. You can email me. We have a big team of researchers, PhD students and research
fellows. We will have an outreach coordinator soon. So yeah, just check out our website,
check out the people, our instrumentation, our labs, it's really exciting. We will be
having probably a launch of the fossilisation lab in next year, we hope, for high school
students and yeah. Jessica Morrison:
Fabulous. Well, we'll make sure we put all of those details in the show notes for people
to access. You've been listening to The Future Of, the podcast powered by Curtin University.
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