 I wanted to talk to you first about your research into coral coring. Could you describe what coral coring is and why you do it? Yes, the coring we're doing is a bit unusual. A lot of people core individual corals where they'll go out with scuba, find a large coral balmy, and they'll core into that to get a recent paleo climate record because the corals, sort of like trees, they have annual growth bands that you can count and see which year is which, and then we can perform geochemical analyses and get temperature, pH, water quality, a lot of different sort of information, but it's dated. The coring we're doing here is on a coring platform and we're getting reef cores where instead of finding an individual coral out on the reef front, we're drilling through the reef flat, straight down, in order to get the historical record of the last eight to 9,000 years of reef growth. And so you get all the things the reef is made of, you get corals, you also get sand, gravel, all the things you see on a coral reef may be accumulated underneath where you're coring. And that way we can get records when we get individual corals of water temperature, pH, water quality back through the last thousands and thousands of years. And so it's basically paleo climate data. How far down do you have to get to get eight to 9,000 years worth of data? Well, the modern Great Barrier Reef is only about eight to 9,000 years old and it's sitting on top of a limestone plateau that was made by the last coral reef when sea level was this high during the last interglacial, so about 130,000, 20,000 years ago, that made a reef. And then of course sea level fell down to as low as 130 meters lower than modern and then it's come back up. And it was only eight, 9,000 years ago when you flooded those old Pleistocene, the last reef, which was high and dry all in between. And then you've, as sea level came up, the reef could grow back up under it. And our research is much concerned with how fast did the reef reestablish once you flooded on top of this limestone? And then how fast did it grow up? Did it keep up with sea level as sea level rose during the deglacial as you're rising sea level back up to modern levels? Did it keep up with that or did it lag behind that? And then once it did catch up, the reef has to grow sideways because the corals and the reef can't grow out of the water. They can't just keep growing vertically. So wherever you get this core down, you'll only get one growth increment, but out here you'll get maybe younger corals because it reached sea level here and then it starts growing laterally and so your young things may be in another direction, seaward. And so we're getting nests of these cores in order to get the full picture of the vertical reef growth and the lateral reef growth. So I guess looking in the past gives you some pictures into how corals can adapt to changing conditions then? Yes, yeah, exactly. The ultimate change in condition is this was limestone with kangaroos jumping on it before it got flooded. And so you've changed that. You've had to wash off the plants, any soil that developed. You've had to clean it up as marine waters came in and then at some point you had those corals that re-established the reef and the entire Great Barrier Reef was high and dry and so you had to get larvae in and build it up afresh in that little amount of time through the Holocene. And so understanding did you start with different communities? Did you have these great pioneer coral communities that started the reef off and then they shifted into the coral communities we know now? There's all kinds of questions like that and the only way we can answer them is by doing this. So have you found that corals do recover or they are able to adapt to changing conditions quite quickly? Well, yeah, quickly is an interesting question. We're looking at thousands of years of data, how quick is quick. And that's the real problem with the problems we face with human induced climate change. We may be changing things quicker than they've happened in nature. As a geologist, I never worried much about coral reefs for a lot of years because they're able to come back from being dead. You know, this reef was dead only 10,000 years ago, at least here. There were corals out in the coral sea somewhere and refugia. And we know that there were corals along the continental shelf edge that the Integrated Ocean Drilling Program drilled some time ago. And so those reefs now we have some data. And there were reefs off but the Great Barrier Reef was gone entirely. And through the quaternary, we've had glacial interglacial cycles at 100,000 years to 40,000 year cycles. And so the reef's dead, reef comes back. Reef's dead, reef comes back. Reef's dead, reef comes back. It gave us a bit of a false sense of security about resilience. And that's why we think so much about resilience. And of course, then you have the work about intermediate disturbance that maybe the diversity on reefs is because cyclones come through, wipe things out every now and then. New corals have a chance to get a foothold and you never go to this climax community where you're dominated by the one coral that's best at doing what it's doing. And so we think, wow, corals like to live in these incredibly fierce environments. Sea level is a rough place to be. Storms, waves. And you go from the beautiful, glassy weather that we had fortunately last week to the kinda windy, wavy stuff. And of course, the cyclone, it moves. Blocks that can be 10 meters in diameter around. I mean, it just bashes everything, kills globs of coral and everything. And reefs inhabit that environment. They're happy to do that. That's what they do. And so everybody's thinking, wow, coral reefs can handle about anything. They're tough. But of course, then you throw in people and you fish on them and you change coastal process. You degrade water quality. And now with global warming, the other horrible thing about corals is they commonly grow best right at the tolerance of the temperature that will inevitably kill them. They like to live on the edge. Thrill seekers, you know, in so many ways. And so if you make it a little bit warmer and they don't have time to adapt, you know, then you get the coral bleaching issues. And then of course, the certification. I don't like that word so much. The ocean's still massively alkaline, but you're dropping pH. That can have things that are worse than, you know, corals, I'm not that worried. Corals, biologically, they'll expend energy to make their skeletons. Maybe they'll grow slower. There's all kinds of studies. Corals can grow without a skeleton if you put them in acidic enough water. Certain species can. Some lovely experiments done. There are other things out here though that are non-obligate calcifiers that accidentally make calcium carbonate. And there's some of the things that make the reef really rigid and hard. And they're microbial communities. They make microbialites. And so these rocks made by microbes, they do a lot of the hardening to really glue the surface of the reef together and make it rigid enough that when a cyclone comes, it doesn't wash the whole reef edifice away. They make hard rock out of it. And they don't expend any energy to do that. It's an accidental byproduct of their metabolism. And if we decrease pH enough to make it where they don't calcify anymore, that could have a significant effect. And the beach rock, you see, that's just marine cement. There are microbialites in that as well. If you lower the pH enough and you stop making beach rock, then caves like this, that's one of the major things that protects the cave from erosion is that beach rock. So there's a lot of physical chemistry thing that doesn't relate to the corals that might actually be more significant in terms of some of these issues. You mentioned how originally you weren't that concerned about corals because you could see how resilient they've been through the Earth's past. At what point did you start to realize that maybe they're being stressed beyond their ability to adapt? It's really in the last decade. And I think that the thing that probably made a big difference is just the concept that a lot of scientists in Queensland have been doing, but around the world looking at shifting baselines that you look at a reef today and you didn't realize it was already degraded from fishing, even from indigenous populations and not to say Australian indigenous populations, but just that human activity had already caused degradation in a lot of reefs and you thought you were looking at a healthy reef and it wasn't even healthy then. And the news that the Great Barrier Reef has actually got degradation that we didn't realize from fishing in particular. And you know the inshore reefs from land use. If you're gonna dig and if you're gonna plant clear trees, you dump things out into the rivers, this stuff gets out. And we've killed a lot of inshore reefs, same as in the Caribbean, they cut down all the trees for fuel, runoff, carry sediment out. Reefs don't like the nutrients, they don't like the sediment. And you can just simply kill them off. The Great Barrier Reef, so many reefs are far off shore, they're a little bit safe from that, at least, but fishing. And then of course, crown of thorns, cyclones and these natural sort of things just compound on what's anthropogenic. And it's so complicated. A lot of people probably feel like they know exactly what's going on. I know, I don't know what's going on, but it scares me that I can't say I know what's going on because I'm interested and I'm studying these things. One of the big factors with the Great Barrier Reef is crown of thorns, as you mentioned. Has human activities had a role in crown of thorns influencing the reef? Well, you know, a lot of people think that it has. But it's a hard thing to say because this is where we need these paleo records to see earlier records of outbreaks that are 5,000 years ago. Could it be that this can happen sometimes? We have such a short timeframe to understand things based on instrumental records for climate, for instance, and based on observations and fishing reports. We just have a snapshot in terms of what makes the reef. It makes it very, very difficult to know. Maybe occasionally these things go nuts. There's some evidence to suggest that's unlikely and that they kill off corals in areas where the reef just doesn't seem to recover anything. Well, if they had done that before, there wouldn't have been a reef here in the first place. And there's been a lot of argument like that. Efforts to go back and look for them in the record are stymied because coring out here is a hard thing to do. Trying to understand these issues, it really is hard. Even things like cyclones, there's a lot of press out saying, oh, cyclones are more numerous and worse than they've ever been before. But if you look back, they look on the Great Barrier Reef. Cyclones went through a period from the 70s up through into the 2000s where there were way fewer cyclones than there had been in the previous. And an interesting paper was presented, and forgive me, I can't remember who presented it a few months ago at the Australian Coral Reef Society meeting, but he looked at these data and he said maybe our idea of coral cover is based on a period of infrequent cyclones and that normally there would be less coral cover. So maybe it's not as bad as we think based on the coral cover we're seeing now. You'd like to, maybe that's a little ray of sunshine, but the data certainly showed that the frequency of cyclones over the last decades is far less than it was in the many decades before that. But of course, there seem to be more bigger cyclones in the end of that data set. But if you could take that data set further back, maybe there would be bigger ones, you know? That's why we need paleo data. We need to get back thousands of years of data instead of just hundreds of years of data. Is a paleo data able to provide any answers about psychoanactivity going back thousands of years? We hope so. We've been able to do pretty well with over the last hundreds of years. I have a colleague at UQ who has dated reef blocks that have been thrown up in China and here in different places and looking at the ages of those in sediment piles. And you find frequency distributions that suggest that there's a high cyclonic activity, high cyclonic, and they could even date some of them and for the really recent record, tie them to particular cyclones. Say this was thrown up in that cyclone. And you'd get an age distribution where corals of about immediately preceding that cyclone were common as this rubble on the reef flat. There are ways. The older you go back, the harder that gets because you need a lot of numbers in order to play the statistics to see if it's reasonable or not. As you look back over thousands of years, do you see many natural cycles in climate? Yeah, well, we know that there are a lot of interesting smaller scale cycles that operated a lot of different potentially periodicities, but at least cyclicities at the thousands of year levels, some at the hundreds of years, some 11 year sunspots. All of these different cycles potentially have effects, especially that when compounded upon each other might lead to a swing in something else, knowing where we sit on those different cycles, what drives them, and what their results are through time. Does it cause temperature to go up a little bit and down a little bit, up a little bit, down a little bit? Are there things like that in the record? I'm very keen to see if we get corals at the right age in some of our cores, the medieval warm period, some people say, oh, that's a local effect. It was a local effect in quite a few places based on good data. Could we see that the water was actually warmer on the Great Barrier Reef during that interval of time? That would be so important because then we might figure out, well, what could cause that? I mean, what is driving those smaller temperature changes? What happens when we compound those cycles on top of anthropogenic changes? Can we recognize what the contribution is? If we can't understand the natural stuff, how do we deconvolve what's anthropogenic and get better predictions? So I think that the paleo record is critical for that and it's really the only place you can get it. One thing I was curious about was whether signals like the medieval warm period or the little ice age appear in your coral data? Well, we will find out, I hope. We have to get corals of those ages and you don't know what you're gonna get. You're sitting on this beautiful reef and you say, let's put a core down here and you don't know what's under you. And one of the exciting things from the last core we brought up is we had a Parides individual coral that looks like it's more than two meters in thickness where we cored through it and that was 14 to 15 meters below the current reef flat. And so we'll date that coral. It'll be potentially hundreds of years of paleo climate record, sea water temperature, water quality and we'll know the age. And so with luck, it'll fall in an age that's interesting. We're very interested in around 6,000 years to 5,500 years, for instance, because the coral reefs in Morton Bay died at about 5,800 years at all bathymetries at Cleveland and Wellington Point. We had a paper out last year and dated corals across the entire surface and they basically all stopped at the same time. And there's a lot of things that could do that in Morton Bay. It clearly wasn't Europeans 5,800 years ago and it wasn't the indigenous people either. There's some natural thing that killed off a huge beautiful coral reef in Morton Bay. And so what happened on the Great Barrier Reef at that time? We know some other inshore reefs farther north had issues at that mid-holocene, about 5,000, 6,000 years ago too. Some reefs stepped back, some reefs died. There are a lot of interesting things that have happened in the Holocene that we don't know what did it. We know it wasn't us. And that's maybe one of the other things that makes me a little more nervous for reefs. Anthropogenic, we know we're doing some devastating things to so many environments, not just coral reefs. And what happens if one of these things that can wipe out a reef in Morton Bay should happen now when we're already doing all this other stuff? We're doing what we're doing, that's not so great. And then one of these other natural things comes along. What's gonna happen with that? There's so many uncertainties, we know so little. It makes you more and more nervous, to be honest. What are the other ways that scientists are measuring past climate change back before the instrumental record? Well, it's kind of fun, the group I work in is called the Integrated Paleo-Environmental Research Group in the School of Earth Sciences. And we have the Radiogenic Isotope Facility for dating. We have geochemistry in there, but we have people working both the terrestrial record and the marine record. So I'm doing a lot of the work in the marine saw. That's, and a lot of colleagues. Zhenjing Zhao is doing the dating and so forth. We've got a ton of people working. And then you've got people working on the megafauna record, but also on the small mammal and small vertebrate record in cave deposits, where we can also date these with the same kind of techniques and look at faunal change. And then we've got speleothemes, things like stalagmites that accumulate bit by bit by bit by bit. And those give you these nice time series records too, where we can look at things like rainfall, potentially temperature, humidities, the big thing we can get from those, but they're dateable and you can find when it's wet or drier, you can also match that then to the fauna. And one of the big shocks we had some years ago with colleagues at the Queensland Museum and QUT and UQ, we found that caves up at Rockhampton, which are just on shore from where we are here at here, and basically inland a bit, caves there showed that from before, about 320,000 years ago, you had enclosed Papua New Guinea style rainforest at Mount Etna just north of Rockhampton. I mean, that's tree kangaroos. That's the full on real rainforest stuff that occurs now in Papua that you don't even have in Australia. And then by about 280,000 years ago, it had gone to desert. I mean, it had just eridified. All of that ecosystem was gone and it had become arid. And then it's slowly gotten a bit more humid back to what we have today. Well, we had no clue until we started doing this type of work that that level of environmental change had happened from Papua New Guinea to out back to Longreach over the space of some tens of thousands of years, that recently. And I mean, we're talking hundreds of thousands of years, but still that's a big whack of change. And now we're pushing that to other cave systems where you can record these types of things and where you can date the faunal assemblages and looking at other big changes. And that's one place. How broad was that? Was it a little rainforest refugia that finally went? Or was it a broader thing by being able to date these different types of deposits and look at the marine record as well as the terrestrial? We can weed out local effects if you see the same kind of things happening in the marine and terrestrial that are dating at the same time. You have a high probability that you're looking at a more climate related sort of issue rather than a local perturbation of some kind. And so we're really keen to look at that Holocene record that last 10,000 years or so in caves and we're working on some caves up at Mount Etna now carefully layer by layer looking at the different little fauna and I've got these guys who love to look at rat teeth and so forth. We're trying to learn to extract geochemistry from those teeth as well to look at diet, potentially migratory patterns, quite a few different things to really tie down the ecology. Then you can tie that to the climate signatures that that ecology requires. And then date it in with U-series dating so that you know when it was. And then we can start comparing, well on the reef you're seeing this, on the coast you're seeing this. And then maybe we'll start to figure out a little bit more about these climatic issues that have been happening over the last 10,000 years and it'd be nice to find good news. But I mean, all news makes you better fit to model and potentially have predictive models that will give us better results. So our scientists using, let me see if I understand this right, fossilized rat teeth to work out what these creatures were looking thousands of years ago. Yeah, it's amazing the way things are going. You can look at the carbon isotopes in teeth and get an idea whether they were eating grass type things or whether they were eating shrubby or fruity type things and so forth. And so that gives you an indication of what the vegetation was like in that region. And you mentioned also cave dropping. So is that looking at what creatures were depositing droppings in that cave over thousands of years? Yeah, well, commonly you get owl roost deposits are wonderful because owls fly out and they sample the small vertebrate community from a wide area. And so if you can get an accumulation under an owl or other predators, there's Tassie Devils and Sarcophilus, these guys carry, and they chew bones up a lot. They don't leave you a lot and the ghost bat, Macro Dermagigus, these things don't leave a lot either but occasionally they drop a bit on the floor that's still identifiable. They chew their food up really well, teeth and all. But all of these things do bring fauna in and of course the odd beast he falls in or wanders in and can't get out. And so you do get a good record of the local ecology that way and stratified, they just build up layers and layers and so you can work your way back through time. If you're lucky and you have a bit of a flow stone that's pretty clean, it can be dated and you have a date between that layer and that layer and you can bracket and little thin straws, the starts of stalactites on the ceiling, they don't last very long, they're fragile, they commonly fall in and they usually fall, I mean they're not gonna hang up there for a long time and then fall in way later so they commonly provided a relatively close date to the layer they fall into. They're not a whole lot older than that layer and so you get a lot of ways and we're trying to directly date the teeth and bones as well. I have a colleague who's doing some wonderful work with that, Gilbert Price. And if we can date individual bones then effectively then you won't need to worry about whether they're bracketed with nice flow stones which are easier to date now. So we're trying to get these things done technically very challenging. So it's like building a jigsaw puzzle using droppings and stalagmites and fossilized bones. It's everything, you have to be holistic about your data. Nobody can just specialize and say we're gonna understand everything based on this one record, like an ice core record or one deep sea core. We need to use everything at our disposal that has a historical record because it's so hidden miss on what gets recorded in a given place you have access to the samples. Most history is gone forever. You think of everything that's lived on the earth. If you had a fossil remain of it, the whole earth would be nothing but fossils. Most things that die are eaten, consumed, destroyed, oxidized, leave no record at all. So these fossil deposits where you get this lovely history preserve are not that common. And that's why I love a quarry. I study rocks that organisms make and try to understand how the chemistry of those rocks tells you about the past environment and how it's changed by things that happen to rock through time. And I work on some really old rocks too, not just these really young rocks. But if we can understand those records and reefs build a nice sequential record too, the problem is it's under the living coral. And so whereas in a cave, you might go in there and dig a hole in the floor, it's very, you don't wanna dynamite a trench in the coral reef. You'd love to know when they're gonna do it for a harbor or something like that so you could be there and actually document everything. If it's gonna happen, you wanna at least get the scientific data. But the best we can do now is put little skinny cores down, but we put them out in geometric patterns and transects so that we can get the maximum data. Any one, a single core tells you something, but you wonder, oh, I wonder which way things are going. You don't know. So by putting down several in a row close to each other, that's when you can start really seeing, well, it grew up like that, then it started going that way and you can date when that happened and you can see what the water temperature was and you can see which corals were happy. I guess on that front then, I don't suppose you could describe a little bit more about the actual process of extracting a core out of a car? Yeah, well, this will be a little bit emotive. It's a drilling rig and so you have a drilling rig. It spins a pipe that you have a bit on the bottom, but it's hollow and you grind a whole shape hole down, but the rock in the middle doesn't get ground up. It goes up the inside of the pipe and we have a one half meter core barrel and so you can drill down a meter and a half and then everything you're drilling through gets caught in this pipe and then you pull that meter and a half up and then you go back down and drill the next meter and a half and you pull that up. Well, when you're down there 20 meters, there's a lot of meter and a half, so you have to take in one pipe at a time. You add them in, put it down, add them in, put it down and then you have to take it out, bring it up, take that one out, bring it up, take that one out, up and down, up and down. We've got where down the bottom, it takes about 45 minutes to an hour to get a core barrel from 15 to 20 meters down and so it's a long hard slog. It's taking us about two days per core, so 10 meters a day basically to get these and we're about to start coring a little bit deeper and just get a little more record on the bottom. But it's hard slog, but it's like a drilling rig and you're out there with tools working and but you're pulling up this paleoclimate record. Does the paleoclimate record tell you anything about sea levels in the past? Well, you know, we already have a lot of data for where sea level was at different times. From coral reefs, coral reefs are your best sea level datum because a coral reef grows up to sea level and then it has to stop. It can't grow up anymore, so it grows out and individual corals do that that you see on the reef flat. You get micro atolls, one colony on the reef flat grows up, it reaches that low tide level or the ponding level and then the top dies because sooner or later it gets a cold night or a bad thing at low tide, but it keeps growing out and so you get these flat top corals. They tell you where the water level is and so that's been done all over the place, you know, at different reefs around the world to construct what the de-glacial sea level curve was like and where it was at a given time. Then we can drill down here and date our corals and corals don't always grow up to sea level. When you first flood this platform that was here, sea level may have risen faster than what the reef could grow up under it and we call that a catch up reef. So you have a reef community is trying to catch up to sea level, it's growing straight up. Once it gets up, then it can only grow sideways and you end up with this beautiful datum. Those are the kind of things we're trying to figure out by dating these corals. Where did Heron Reef reach sea level first? When did it start growing this way or did it grow more that way? You know, which directions did it grow? Did it grow up all in one kind of line and then grow out or did it grow up in a few little spots and then they coalesced as they caught up and grew out? We don't know those kind of things, but we'd like to and we'd like to see which corals were best at coping with sea level rise. That's a handy thing to know if we're worried about sea level rise. I think the corals are gonna handle that okay. Decays may have a lot more trouble. You know, mobile sand corals will just grow up and say, oh, more water to grow in. We're happy as Larry unless it's hot water to grow in. But you give them more space, they'll fill it. As they have done here at Heron Reef, when they changed the bund wall around the harbor, they added about 20 centimeters of water depth to the reef flat out here past the wreck just off the research station. And that's why you've got all this crop right there now. It's grown up, that wasn't there 10 years ago because the water level was lower. It's grown up and taken up that space. So in a decade, the corals there have grown up 20 centimeters, no problem. Now they're dying because they've reached where they can get, they're eroding, but you're getting some of them are being cemented over by coral and red algae. Some just marine cement coming out of the seawater, no doubt is lithifying them. Microbes may be lithifying them deep down inside. And that will become good new reef flat. And it only took a decade to grow up that high. So there's hope for corals. Of course, it hadn't been a cyclone here in that time. And so a cyclone just, that's the weed of the sea, grass that Acropora cyclones or lawnmowers for those corals turn them into sticks and then you have big gravel piles and sand. And then they have to start over and grow back up in that same space. But that's natural, that's how coral reefs behave. And as sea level rises, the corals will grow up to that new sea level if the corals are healthy enough. There's periods in Earth's history when there were practically no carbonate corals. What does that tell you about coral's ability to adapt to climate change or other corals? Well, you know, the sclerotinian corals evolved, you know, back after, well, I have colleagues, we debate these kind of things. But you know, around 250 million years ago, they're bouts at the end of the Paleozoic, the Permian. You had a giant extinction event and it killed off the earlier types of corals, rugos and tabulate corals. They weren't great reef builders anyway, but there are little reefs, you know, out past Rockhampton that have a higher coral content than modern sclerotinian coral reefs like the Great Barrier Reef. I mean, in terms of density, some of these older Paleozoic reefs, they were quite small, but I mean, they're good coral reefs for the Paleozoic. Then you had your sclerotinian corals evolve and they've gone up and down a little bit, but they were making reefs fairly soon after they evolved of different types. But the longer term geological history of reefs is an amazing thing with huge amounts of climate change relative to what we're thinking about in the modern. You know, you go into ice house times when you have glacial, interglacials, and then you have green house times, like through the Cretaceous and then the Paleocene, when there was probably no ice on Earth during some of those times, even on mountaintops, it was just hot. There were dinosaurs and conifers and the Arctic Circle kind of things and Antarctica. No continental ice for certain. Massively different climate, huge amounts of CO2 in the atmosphere. The corals were happy to live in that, but of course, it's a double-edged sword when you have a lot of CO2 in the atmosphere and you have rock exposed. You chemically weather, a bit of that CO2 dissolves into your rainwater and becomes carbonic acid. And it will weather silicate rocks like minerals in granite, you know, these volcanic rocks. It weathers those and one of the byproducts is bicarbonate, which flows to the ocean. The carbonate that's in the ocean that organisms make skeletons out of isn't from the CO2 in the atmosphere so much. It's from weathering rocks on the continent. So if you build your CO2 up gradually, you get more acid rain, which pumps the ocean full of alkalinity and bicarbonate and it acts, you know, in a way as a buffer against the high CO2. And organisms just biologically can evolve to things that happen slowly enough, we assume. So you always had some corals going. I reckon you always did. You don't always have their fossil record on them. So the weirdest things we just found on a dredging back about two years ago of the Tasmanid sea mount chain in the Coral Sea but just off the continental shelf of Australia. We were dredging these, you know, volcanoes. They all formed down at a latitude around Tasmania, we believe, and then the continent's been moving north and carrying them north, so they're older towards the north and they get younger and younger down towards Tassie. But they all had coral reefs on them and nice looking coral reef facies from the bit that came up in the dredges. But those reefs would have formed at latitudes closer to Tasmania than even to Brisbane. Never mind up here where you have the modern Great Barrier Reef. They were forming really high latitude, you know, 40 degrees and things like that. So we're quite keen on understanding those. They were probably 15 to 20 million years old but I don't have firm dates on those yet. It's a little harder to date things at that particular age. But coral reefs have done different and crazy things at different times. Depending on what climate was doing and what the world was like, circulation, there's so many different, you know, variables. And of course, your record of the rocks, you just may not have them. You know, if we hadn't dredged those, we wouldn't know that those were there. Right. So when there were periods when there were less corals, what was the main drivers of the... We don't know yet. Yeah, we just don't know. We don't understand why, you know, during the Maya scene, you would have had such a greater latitudinal range for some of these corals. Maybe some of them are happier in cooler water or maybe it was a lot warmer. But, you know, we don't know. What would you say is the most interesting scientific questions in your field at the moment? Oh, gosh. I would almost be cynical and say, whatever you have money to study. The problem is it's all so good. That's the shocker. We know so little. Everything is important. I mean, there's so many things. I think at the moment I really would like to provide more and better integrated data for paleoclimate through the last thousands of years because the need for that to inform management today is really critical, you know, as a environmentally, I guess, when you say jaded person, I would really like to see something survive on this planet past human beings. And of course, I'm not sure there's anything we can do to really manage resources on a resource by resource basis. I think we need to think a little bit more about population control from a human point of view. That seems so unpopular now and where we've got people in charge of the world who seem to say, growth, growth, growth, bigger population, buy more white goods. We, you know, everyone has a footprint. Everyone is responsible for these problems. I'm often amazed environmentalist mates of mine are saying, oh, we've got to stop mining coal. And you just have to say, mate, we're not burning it and turning it into electricity because those nasty miners mined it, you know. They're mining it because we want the lights to come on. And that's the same with every resource. It's all what we're using, you know. And the more of us there are, especially with developing nations who want to have some quality of life, here we are extravagant, you know, Western quality of life, giant energy use, giant use of all kinds of just materials. And then we're going to tell them, ah, we want to save the planet. You guys can't have any, you know. But we've been terribly ineffective at getting populations to cut down on their use of energy and to cut down on their use of things. What do you do? What we've got to do is try to have fewer people because everybody needs a certain amount. And it, you know, you can have some renewable energy, you can have some of this, you can have some of that. But the resources we use come from the earth, the food we eat. I mean, people complain about mining. Get on Google Earth, find a mine. Go to Gooniela, it's gigantic. It's a huge coal mine. Then scan out and you'll see it's 1% of a giant agricultural area where every native ecosystem has been stripped off the face of a giant area. Almost all the environmental damage there, it's done by agriculture because we want to eat, not by that little tiny mine there. And so I think we have to focus our environmentalism on the problem and it's us. We're the problem. That my problem as a scientist is I see everything we're trying to do are stitching the corner of a bandaid that's coming off and the problem needs sutures of the giant wound that goes out of sight of your bandaid. We're not, you know, if we're gonna do something useful we've got to address bigger things than the small environmental issues that get all the, well not all the press but so much of the press. We've got to have fewer of us so we need less of all this stuff because we're not disciplined enough to be good environmentalists and useless. Maybe I'm cynical but I don't see the world all of a sudden saying I'm gonna bicycle to work and by the way if that bicycle has a titanium frame that's a big mine or a bunch of sand mining on Fraser Island to get that titanium. It didn't drop from the sky without resources. You know, what do you do? This is a bit of a change of pace but I'd be interested in hearing how you got into your area of research. What was your journey to where you are now? Well I'm a paleontologist and interestingly my dad was a geologist and my mom was a biologist but what really got me was your college textbooks. Ralph books bombs, animals without backbones was on their shelf and I would look through that book long before I could read and it had crabs and worms and corals and these things and then my dad he had shock and twin hopefuls principles of invertebrate paleontology. That Honest of Goodness is the first book I ever read cover to cover by choice. That wasn't C-Spot Run, blah blah, school books that, you know, in school. That was, I wanted to know what are all those cool things trilobites, brachypods, what are all these cool things in this book and of course my mom and dad could tell me and so I fell into paleontology as a love. When I was knee high, I mean I couldn't help it. I wanted to know what all those cool things and those pictures in those books were and so I'm a fortunate individual. I aim toward this career from the time I was six years old. I've only ever wanted to do this and now I study rocks that are made by organisms and that's paleontology and as much as modern coral reefs are beautiful ecology with corals and fish, I can assure you a coral reef is a rock and it's a big rock that sticks up and can withstand waves bashing on it and it has a thin little film of biology on top of it but it is that biology that constructed it but the reef itself is a rock. It's mine, I mean it's what I do. All these biologists think the reef is theirs. No, the reef is for geologists because almost all of it is geology but of course it's the geology made by biology which is perfect. It's what nature can do. Do you have any thoughts on what scientists can do to better educate the public about climate change and about science in general? You know I think scientists need to, it's a difficult thing, there's so few scientists. I mean we've got more scientists now than we've ever had. A lot of scientists are solving industry type problems and so forth but you know we have more environmental scientists than we've ever had but there's so few of us considering how much environment there is to study and considering the uncertainties and what we do and don't know. We feel overwhelmed and I can't speak for everybody by any means and I wouldn't want to and I can assure you a lot of my colleagues wouldn't want me speaking for them but the point is we feel like my God how are we gonna figure all this out? We've got so much to do and it's so expensive and it's so hard and we need more students, we need more of this. So a lot of people just oh I don't have time to talk to the media, I don't have time to talk to people. I think the education side is so critical and I teach undergraduate, I teach first year, second year and third year courses in the School of Earth Sciences and yeah I resent marking and I resent the bureaucracy and the admin, you know I can't help it. I want to be doing this, I want to be doing the research but I take my education side seriously with my students, these are the guys who are gonna solve the things I'm not smart enough to solve. I hope to goodness I can inspire someone who's smarter than me to come out and make sense of some of this stuff that I look at and think oh my God there's so many variables here, how can we constrain this? At what level is anything we're looking at here gonna be useful? I often feel like that. You look at the heterogeneity on a reef, here you've got this, there you've got that, come back two years later, oh goodness that's gone now, you've got something else there, now you've got this. The longer you come here, the more you realize how difficult the problem is and you think oh we're gonna have to average all of that out over a different time interval and a different spatial level and we're gonna have to do all this and it just gets harder and harder and so if we could get people to know more and from a political point of view, people just need to be educated to be in democracies. You need to know, you can't afford to not know when you're voting on things that are important and so public education is critical but it's hard to do and there's so little trust now too there's a weird undercurrent in society that they blame scientists for a lot of the problems because scientists develop nuclear weapons and so scientists fault and you get an undercurrent of that and often now there's a trust thing, they say oh these guys are just trying to destroy my economy with climate change stuff, I don't believe them and then oh there's the climate deniers, I don't believe them. You have polarized science, we need to have scientists who can talk about data and uncertainties and say look I don't know the answer and we don't know so many of them. We may know something but we often can't answer what the public wants, they just say give me an answer, should we do this or that? Often in science we say well probability is, maybe you should, you know. Trying to convince people and educate people when that's the best you can do is pretty difficult and I think a lot of my colleagues are a bit jaded from it and just don't even wanna try sometimes but having the opportunities difficult at the same time and making that time. So would you say your approach is inspiring the next generation who you hope will solve the problem? You know, I wouldn't like to say that's my approach because I have little control over it. I would be thrilled to death if I could die having inspired some guys to carry on who did better than I did with these issues, you know. And my graduate students who I've turned out in the past, I love to see them. I've got some who are doing wonderful science and it's what I'm proud of and all my students. I've got students in industry too and I've got students in all kinds of areas. That's what turns me on in so many ways but in the end I wanna know and I don't care if it's a guy I had in first year who figures it out and says, oh, by the way, I figured this out. I'm gonna say, oh, I wanted to know before I up in Karkat, I wanna know. The more people who are working on what I wanna know, the happier I'm gonna be but we'll never have enough. One last question. Could you give a short statement just about the topic of how humans are influencing our climate perhaps from your perspective or from your research? Well, from my research, it's a little harder to say from the viewpoint that I'm trying to get before the influence was as big as it is now. I mean, CO2 is obvious. You can measure it yourself. It's empirical, you know, CO2 is going up. It always gets trickier from their greenhouse gases or pure physics, they have to make it warmer. There's just no question about it, it's physics. You can't argue with maths and most people don't know enough to try. Obviously, this is anthropogenic. The worst thing is just ecosystem destruction that you can see. It's empirical like that Google Earth. Go look at what ecosystems are gone due to agriculture, for instance. And I mean, what are you gonna say? Well, we just won't eat. We have to eat. But look at the fisheries, you know. And mind you, there's a lot of export fisheries and whatever, but in the end, fisheries are about people eating. And trying to figure out how coral reefs can provide the services they do, provide the food they do, to communities who depend on them for their food without destroying the reef, like so many in the Caribbean, where they eat fish that are, you know, five centimeters long, because that's the biggest fish they can catch now. You know, surely there's gonna be a way, but it's obvious that people are doing this. I mean, there's no question about that. And the bigger the population, the bigger the footprint, because each one of us has a footprint. We each burn a bit of coal. We each use a bit of aluminium. We each use plastic, you know, for all the hatred of oil companies. You can buy a liter of water, costs more than a liter of petrol. And it didn't cost as much to produce as that petrol. But if you wanna hate an oil company, it's gonna be when they say, we're not gonna sell you petrol anymore. They don't produce it and twist your arm to buy it. They'll stop as soon as you stop using petrol. But then in plastics, you know, what would we do? Stuff comes out of a petroleum well. You'd be amazed at what you depend on comes out of a petroleum well. It's not just petrol. So it's people, it's empirical. And it all adds up.