Good news! Study says the foundation of aquatic life can rapidly adapt to global warming

From the UNIVERSITY OF EXETER

The foundation of aquatic life can rapidly adapt to global warming, new research suggests

Important microscopic creatures which produce half of the oxygen in the atmosphere can rapidly adapt to global warming, new research suggests.

Phytoplankton Source: Wikipedia

Phytoplankton, which also act as an essential food supply for fish, can increase the rate at which they take in carbon dioxide and release oxygen while in warmer water temperatures, a long-running experiment shows.

Monitoring of one species, a green algae, Chlamydomonas reinhardtii, after ten years of them being in waters of a higher temperature shows they quickly adapt so they are still able to photosynthesise more than they respire.

Phytoplankton use chlorophyll to capture sunlight, and photosynthesis to turn it into chemical energy. This means they are critical for reducing carbon dioxide in the atmosphere and for providing food for aquatic life.

It is crucial to know how these tiny organisms – which are not visible to the naked eye – react to climate change in the long-term. Experts had made predictions that that climate change would have negative effects on phytoplankton. But a new study shows green algae can adjust to warmer water temperatures. They become more competitive and increase the amount they are able to photosynthesise.

Algae examined by scientists which lived in warmer waters became fitter, and more competitive, proving that these tiny creatures adapt well to climate change. This suggests that this species could continue to be a plentiful source of food for aquatic life even if temperatures rise.

Previous studies which sought to answer this question have been conducted only in laboratories rather than looking at how phytoplankton reacted to real conditions. In contrast this research, which has run so far for ten years, has allowed researchers to examine how the green algae fare in their natural environment, where they are exposed to a more complex environment, and competitors.

Scientists at the University of Exeter, working with colleagues from Imperial College, and Queen Mary, University of London, have for a decade monitored ten tanks home to the phytoplankton with freshwater heated to four degrees centigrade above the ambient temperature. This is the rate at which our climate will have been warmed by the end of the century. The temperatures of ten other tanks were kept at normal temperatures. All the tanks were kept outside the Freshwater Biological Association’s river laboratory in Dorset. All twenty tanks were populated with the same types and proportion of various freshwater phytoplankton, zooplankton, invertebrates and plants. In the laboratory scientists tested how much the algae could photosynthesise, how fast they were growing, and how well they outcompeted organisms from the ambient ponds.

Lead author Dr Elisa Schaum said: “Phytoplankton may be microscopically small, but they are essential for all aquatic life. They provide food for zooplankton, which are then eaten by fish. Aquatic ecosystems produce the oxygen in every second breath we take, and are responsible for the oceans’ capacity as a sink for carbon dioxide.

“Other research had suggested that increased temperatures can pose problems for some types of phytoplankton. But we have shown that algae adapt very rapidly and that the mechanism underpinning their evolutionary response is linked to higher rates of photosynthesis – they can produce more energy, and channel it into faster growth rates and a better capacity for competition with other algae. They divide once a day and live in large populations of thousands of cells per millilitre of water. This means evolutionary changes are made through a few hundred of generations within a couple of years.

“It is important to recognise that climate change is a serious threat to aquatic ecosystems. Although the green algae monitored in our study cope well with elevated temperature, and may be able to sustain populations of organisms that eat them, we do not know yet what will happen to other groups of algae, and whether or not they will adapt through the same mechanisms.”

###

Adaptation of phytoplankton to a decade of experimental warming linked to increased photosynthesis by Elisa Schaum, Samuel Barton, Elvire Bestion, Angus Buckling, Bernardo Garcia-Carreras, Paula Lopez, Chris Lowe, Samraat Pawar, Nicholas Smirnoff, Mark Trimmer and Gabriel Yvon-Durocher (who is the group’s principle investigator) is published in the journal Nature Ecology and Evolution.

Adaptation of phytoplankton to a decade of experimental warming linked to increased photosynthesis

Phytoplankton photosynthesis is a critical flux in the carbon cycle, accounting for approximately 40% of the carbon dioxide fixed globally on an annual basis and fuelling the productivity of aquatic food webs. However, rapid evolutionary responses of phytoplankton to warming remain largely unexplored, particularly outside the laboratory, where multiple selection pressures can modify adaptation to environmental change. Here, we use a decade-long experiment in outdoor mesocosms to investigate mechanisms of adaptation to warming (+4 °C above ambient temperature) in the green alga Chlamydomonas reinhardtii, in naturally assembled communities. Isolates from warmed mesocosms had higher optimal growth temperatures than their counterparts from ambient treatments. Consequently, warm-adapted isolates were stronger competitors at elevated temperature and experienced a decline in competitive fitness in ambient conditions, indicating adaptation to local thermal regimes. Higher competitive fitness in the warmed isolates was linked to greater photosynthetic capacity and reduced susceptibility to photoinhibition. These findings suggest that adaptive responses to warming in phytoplankton could help to mitigate projected declines in aquatic net primary production by increasing rates of cellular net photosynthesis.

The formation of organic carbon by phytoplankton (net primary production, NPP) is a key flux in the carbon cycle 1,2 , contributing to nearly half of the carbon dioxide fixed globally on an annual basis 3,4 . There are currently major concerns that global warming will reduce aquatic NPP, due to increased nutrient limitation 5 , and because rates of respiration and zooplankton grazing tend to be more sensitive to rising temperatures than those of photosynthesis 6,​7,​8 . These projections, however, do not account for the capacity for phytoplankton to adapt rapidly to environmental change. Although ample evidence for rapid evolutionary responses in phytoplankton to warming exists 9,​10,​11 , our current understanding is based on highly simplified laboratory experiments, where populations are allowed to adapt free from natural enemies or competitors and where individual abiotic variables are manipulated in isolation. Consequently, we lack understanding of the mechanisms that govern evolutionary responses of phytoplankton to warming in sufficient detail and under a realistic ecological context, to capture the dynamics of thermal adaptation in models of aquatic biogeochemistry 5,​6,​7,​8 .

Phytoplankton growth depends on the balance between gross photosynthesis (P) and respiration (R) 12 . Crucially, as rates of R rise more rapidly with increases in temperature than do rates of P, the amount of carbon that can be allocated to growth after accounting for R declines rapidly as temperatures rise 10 . This imposes a physiological constraint on growth after acute exposure to high temperatures. Laboratory experiments have shown that phytoplankton can overcome this constraint and rapidly adapt to warming by down-regulating rates of R, thereby increasing the potential for carbon to be allocated to growth 10 . If general, this suggests that the mechanism underpinning evolutionary responses to warming in phytoplankton might also help to offset the short-term, exponential effects of temperature on rates of phytoplankton respiration and projected declines in aquatic primary production 6,​7,​8 . However, along with the vast majority of microbial evolution experiments, this mechanism was identified in isolated populations, evolving under controlled conditions in the laboratory. These experiments allow for highly controlled and replicated hypothesis testing, but their applicability in nature may be limited if interactions with other species and/or other components of the abiotic environment influence evolutionary responses to environmental change13,​14,​15 .

Here, we leverage a decade-long warming experiment in outdoor mesocosms 16 (Supplementary Fig. 1) to investigate the mechanisms of thermal adaptation in the green alga Chlamydomonas reinhardtii, embedded in complex, semi-natural ecosystems. Experimental warming has caused fundamental changes to the structure and biodiversity of the phytoplankton communities in these systems 17 ; however, several highly abundant core taxa, including C. reinhardtii, are cosmopolitan across the warmed (+4 °C) and ambient mesocosms. This experimental system therefore provides an opportunity to quantify the mechanisms of adaptation to warming in the context of naturally assembled communities. In line with laboratory experiments on the green alga Chlorella vulgaris10 , we hypothesized that evolutionary changes in metabolic traits, which increase net photosynthesis and thereby the potential for carbon allocation to growth, will also play a role in adaptation to long-term warming in populations of C. reinhardtii embedded in complex semi-natural ecosystems.

Full paper (open source: http://www.nature.com/articles/s41559-017-0094

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98 thoughts on “Good news! Study says the foundation of aquatic life can rapidly adapt to global warming

  1. Algae does better in warm water,
    Another study brought to you from the department of the obvious results.

    • Life CAN Adapt.

      Wow-oh-wow. [no point adding more -oh-wows]

      As if billions of years of adaptation haven’t existed!

      MarkW – I borrow, and amend: –
      “Another study brought to you from the department of the obvious results.”
      “Another study brought to you from the department of the blindingly bleeding obvious results.”

      Auto – astonished that ‘Nature’ [even these days] would give houseroom to such a plea for funds.

    • Yup. Set up a straw man and then knock it down yourself. And get paid twice for researching something that never needed doing in the first place.

  2. The food chain gets a reprieve for a day, until notified it is out of compliance with global BS agenda.

  3. This might be true globally but not in Australia, Oakland, Brussels or the Netherlands. It may or may not be true in the UK depending on when you check.

  4. Scientists have also discovered that plants photosynthesize far better during daylight hours than during the night.

    • Especially the light reactions, ie those which use photons to split water molecules into hydrogen and oxygen atoms.

      The dark reactions, which attach the H ions to CO2 molecules to make sugar, not so much.

      • Actually, the dark reactions don’t just happen in the dark and they need the ATP and NADPH from the light reactions, so the dark reactions will speed up along with the light reactions. (Although the dark reactions can also produce some NADPH).

  5. Shocking result!

    Not.

    Many phytoplankton groups evolved and/or thrived when the seas were much warmer than now, and have survived long episodes of cooler and warmer water, to include really hot water.

    Diatoms might have evolved in the Triassic, but they didn’t take over until the Hothouse climate of the Cretaceous Period and early Cenozoic Era. Dinoflagellates and coccolithophores are more firmly dated to the Triassic.

    Cyanobacteria of course arose way back in the Archean Eon (c. 3.5 Ga), and caused the Great Oxygen Catastrophe in the following Paleoproterozoic Era.

    • Take the Eocene Epoch, second of the Cenozoic Era, for instance.

      Using isotope proxies to determine ocean temperatures indicates sea surface temperatures in the tropics as high as 35 °C (95 °F) and, relative to present day values, bottom water temperatures that are 10 °C (18 °F) higher.

      The Early Cretaceous wasn’t the warmest part of that period, yet even then SSTs were much warmer than now:

      http://www.nature.com/ngeo/journal/v4/n3/full/ngeo1081.html

      “The Early Cretaceous Epoch, about 145–100 million years ago, is generally thought of as a greenhouse period, with high atmospheric CO2 concentrations and high global mean temperatures. But evidence for episodes of cooler conditions, and even transient glaciations, has been proposed. Here we present sea-surface temperature records spanning the period from 142 to 128 million years ago (Berriasian–Barremian ages) from low and mid latitudes, reconstructed using the TEX86 palaeotemperature proxy. During this period, we find sea-surface temperatures exceeding 32 °C at 15°–20° N and averaging 26 °C at ~53° S. These temperatures substantially exceed modern temperatures at equivalent latitudes, and are incompatible with the notion of consistently cooler conditions in the earliest Cretaceous. Moreover, we find little variability in the sea-surface temperature records, even during the Valanginian carbon-isotope excursion ~138–135 million years ago, which was thought to be associated with marked temperature fluctuations. We conclude that the earliest Cretaceous was characterized by a warm, stable climate, with a lower meridional temperature gradient than today.”

      The hottest part of that period was the early Late Cretaceous, c. 90 Ma. It cooled a bit in the latter part of the Late Cretaceous, but was always a lot warmer than now.

  6. Warming temperatures will produce better compost; hence, we can expect a catastrophic increase in home organic gardeners. The earthworm population will go out of control. Global tomato production will skyrocket, overtaking the land in uncontrollable growth that outpaces human ability to consume the fruit. People will get fatter, because food will become even more abundant. Iceless polar bears will roam the Earth now, eating fat humans, thus, causing more human fatalities from polar bear attacks. More people will buy guns for protection from polar bears, but will use their guns in more angry confrontations with one another, thus increasing the murder rate from fire arms.

    It’s just horrible what lies on the horizon!

  7. C. Reinhardtii is a model lab organism. A paper was published in 2011 examining cell growth cycle (time between divisions) at temperatures from 15C to 37C. Hotter is faster (14 hours), colder is slower (26 hours). But the algae thrived at all temperatures. So this Exeter paper is not only not new science, it was a complete waste of time and effort as the answer was known 6 years ago.

    The other reason this paper is silly is that it is ocean phytoplankton that provide the majority of phytoplankton CO2 uptake and oxygen production. C reinhardtii is freshwater, so the paper says nothing about ocean phytoplankton temperature adaptability. But there is nothing to study there. Phytoplankton at the base of the ocean food chain exist everywhere from the cold poles to the tropics. Thousands of species adapted for different conditions. Conditions change, species move. Never going to be an ocean temperature/food chain or oxygen production or ocean carbon sink/biological pump problem. A little common sense can go a long way.

  8. Lots of comments saying this has just shown what we would expect.
    Which is true.
    But now we have actual evidence that life can evolve to cope with warmth, as expected.
    This is real science. They did a real study. It’s not all computer models or thought experiments. It’s observations of reality.
    Let’s welcome real research.

    • I do, but it’s kind of like direct observation of the fact that the earth goes around the sun.

      • And exactly what do you think science IS if it isn’t the direct observation? It really is NOT playing with formulae and creating “models” that don’t fit the subject being modeled BECAUSE they didn’t bother to directly observe what was happening!

      • Chimp, I respect you because you have demonstrated to me knowledge, creativity and a clear writing style.

        But I cannot accept that a “direct observation of the fact that the earth goes around the sun” is worthless.
        If you don’t look you would never find that it didn’t. If it didn’t.

        It took almost two millennia for people to stop trying to prove all of Euclid’s axioms and instead try to disprove them.
        Phlogiston theory is practical. It will work for engineering purposes. Unless you have very good scales.
        Quantum mechanics is certainly ridiculous. Checking that a particle only goes through one slit at a time is certainly pointless.

        Geocentrism was disproved by observing the phases of Venus. Yet how can that be when it can be seen every morning that we aren’t flying around at speed? The air should blow us over as we leave it behind.

        Observations of even the most obvious things are real science.

      • Tom,

        You seem to miss my point, which was that the heliocentric hypothesis was not directly observable when Copernicus made it. What was once an insightful hypothesis is now subject to direct observation.

        Maybe I should have been more explicit enough with that point.

        However science is not only observation. It is also making hypotheses and predictions based upon those guesses, which can be tested by observation. Science seeks to explain, using experiment and observation of nature.

      • M,

        I didn’t say it was worthless, but at this point it is superfluous. That the earth goes around the sun and spins on its axis was confirmed by observations in the 18th and 19th centuries, showing Copernicus’ 16th century hypothesis to be a physical fact. Now it’s a trivial observation.

        Observation of the phases of Venus falsified the Ptolemaic system but didn’t necessarily confirm Copernicus’ geocentric hypothesis. Tycho’s system was not ruled out, in which the sun goes around the earth, like the moon, but the planets (earth not being regarded as one) go around the sun, including Venus. Other configurations also fit the observation.

      • Chimp, Yes you are correct (as usual) about what the phases of Venus ruled out.

        However, I don’t think that the effects of warmer water on phytoplankton were observed and acknowledged centuries ago. It was merely obviously going to be that way – and, of course, it is that way.

        But it hadn’t been observed.
        I stand by my lack of cynicism.

      • M,

        That algae prefer warmer water probably was understood well before that wonderful year for science of 1543 (Copernicus and Vesalius), but perhaps not as a formal scientific observation. As I wrote above, all you have to do is look at a stock tank in summer as opposed to winter.

        The modern history of phycology (study of algae) could be said to begin in the 17th century, with microscopy. But when it became obvious that many algal species grow better in warm water, I don’t know. It has however been well established at least since the 19th century. As a benchmark, Schwendener in 1867 recognized that lichen are a symbiosis of an alga and a fungus. Phycology was by then pretty mature.

      • Well, I don’t really disagree. Lots of evidence shows that warmth isn’t a problem, for centuries.

        But checking everything – every species – is still good.

        Remember, lichens themselves have been re-examined in this decade and found to be more than alga and a fungus.
        Who expected there to be a yeast?

      • As I said, I don’t find this study a total waste, either.

        To me, yeast in lichen isn’t all that surprising, since yeast are unicellular fungi, in fact descended from multicellular fungi.

      • Direct observations can be deceptive. How would have looked if the sun had circled the earth? Exactly the same, no doubt. ;->

      • What?! Around the sun? When did this happen and why didn’t someone tell me??? Maybe a new study is needed to verify. Just be sure to include some words about how the humans are to blame (and, indeed be taxed for it).
        /sarc – as if needed…

    • M Courtney,

      I think the geologic record has already shown that these species, or ones very similar, survived and thrived when conditions were much warmer than today. While confirmation and backup for what geologists have already shown is nice, it is hardly new ground.

      Or maybe I am just jealous since the grant writing organizations won’t give me a grant to replicate previous published work!

      • Case in point: White Cliffs of Dover and chalk across the Channel.

        http://www.dovermuseum.co.uk/Information-Resources/Articles–Factsheets/White-Cliffs-of-Dover.aspx

        “Around seventy million years ago this part of Britain was submerged by a shallow sea. The sea bottom was made of a white mud formed from the fragments of coccoliths, which were the skeletons of tiny algae which floated in the surface waters of the sea. This mud was later to become the chalk. It is thought that the chalk was deposited very slowly, probably only half a millimetre a year, equivalent to about 180 coccoliths piled one on top of another. In spite of this, up to 500 metres of chalk were deposited in places. The coccoliths are too small to be seen without a powerful microscope but if you look carefully you will find fossils of some of the larger inhabitants of the chalk sea such as sponges, shells, ammonites and urchins.”

        The coccoliths (algae) loved that hot, shallow sea. so much warmer than now.

    • It seems life can evolve to cope with cool water, as this study shows. Life obviously prefers warmth.

    • But now we have actual evidence that [ life ] can evolve to cope with warmth, as expected.

      –>

      But now we have actual evidence that live can evolve to cope with warmth, as expected.

      OK with me: got it.

    • I agree completely. Those who freak out about warming can only be conquered with actual evidence. PROVING what we so easily understand and expect, to the hardheaded, especially at the amount of warming and the length of time these guys did, is a great thing.

  9. I like this line –

    “Algae examined by scientists which lived in warmer waters became fitter, and more competitive, proving that these tiny creatures adapt well to climate change.”

    Now the question is this – is it because they adapted to the new climate or have finally started to live in the climate they originally evolved in?

    • Both, since adaptation is an evolutionary process. They adapt to colder water even if they prefer warmer. One way to adapt is to “move”, but other ways involve changing allele frequencies fitter in colder water, ie evolving.

    • TO, this speci s lives at a range of latitudes, and in damp soil as well as fresh water. From first principles, the experimental answer was known before the experiment. See my comment upthread.

  10. “But a new study shows green algae can adjust to warmer water temperatures. They become more competitive and increase the amount they are able to photosynthesise.”

    ……..Immediately followed by

    “A new study shows green algae is inhibited by cooler water temperatures. They become less competitive and decrease the amount they are able to photosynthesis.”

    film at 11

  11. So they used 4C to kill them off and the blighters flourished. Such a heating of the ocean wouldn’t happen in centuries. 2C would have been the most honest experimental design for the upper bound. Better still, with ten tanks, I would have had two at 1C, two at 2C and two at 4C, the latter to test an improbable high. I would also have had two at today’s temp, and two at – 2C below it as an “outlier” to see how they performed. From chem 101, My guess would have been – 2C as having the unhappiness population. Ten years is a long time to test a biased case. This design, to me, is a ‘tell’ that they wanted to report a dramatic GW disaster, we would all be asphyxiated, and not measure a range of conditions of potential climate. They may even have been going to adjust things so that it was a disaster, but Trump’s gave them an idea of an opportunity to change course.

    Man I hate that this CAGW shark feeding frenzy has done this to my trust levels and made me think this way. That’s the worst thing on the list of changes caused by CAGW.

    • GP, it has merely honed your skeptical instincts. Your trust levels should always be near zero until proven otherwise. That is good, because those instincts are needed in many more circumstances than just CAGW. Read ebook The Arts of Truth for hundreds of other specific examples. The Chevy Volt sticker mpge is wrong courtesy the EPA. There is a whole long culminating examples chapter on climate change to pull everything together previously illustrated in 8 thematic chapters drawing examples from finance, government taxation and spending, energy, education, healthcare, nutrition, epidemiology,.. even womens dress sizes and rahmen soup portions.

    • … freshwater heated to four degrees centigrade above the ambient temperature. This is the rate at which our climate will have been warmed by the end of the century.

      Sorry Gary, seems you must be wrong, since the press release is quite clear that this is the rate (sic). You can’t argue with science!

  12. I knew it would be not long before academics were interviewing aquatic life to obtain these phenomenal insights.
    I think Cook et al should run some surveys with the aquatic folk – to see what 97% might think.

    • toorightmate on March 21, 2017 at 3:18 pm

      I knew it would be not long before academics were interviewing aquatic [ life ] to obtain these phenomenal insights.

      –>

      toorightmate on March 21, 2017 at 3:18 pm
      I knew it would be not long before academics were interviewing aquatic live to obtain these phenomenal insights.

  13. The animals I studied have obviously moved up mountains when the climate became too hot, or migrated to cooler climes. This they must have done repeatedly through their 200 million years or so of existence since the earth has been both hotter and cooler than now. Yet they, and the whole biota have survived all these natural climate changes.
    And: algae won’t be photosynthesizing “better” in warmer environments, just faster. And that has a disadvantage as their protein to carbohydrate ration will be lower, so making them worse food. Tropical tubers have lower ratios of protein to carbohydrate (eg taro) compared to temperate tubers (eg potatoes).
    And: for Chimp’s benefit, yeasts can be filamentous, that’s why they are so darned itchy in those delicate and damp places as they growth through your tissues. And in this state they are hard to kill.

    • True, but that’s not multicellular in the sense that, say, a mushroom is. Many single-celled organisms form colonies and even stitch together like that. To include the lowly and ancient cyanobacteria (so-called “blue-green algae”, which they aren’t).

      One reason that yeast form filaments so easily is that their ancestors were truly multicellular fungi.

  14. Didn’t James Lovelock write about phytoplankton releasing a gas that formed clouds over the sea when things got a bit warm? That was back in the 1970’s.

  15. “But a new study shows green algae can adjust to warmer water temperatures. They become more competitive and increase the amount they are able to photosynthesise.

    Algae examined by scientists which lived in warmer waters became fitter, and more competitive, proving that these tiny creatures adapt well to climate change. This suggests that this species could continue to be a plentiful source of food for aquatic life even if temperatures rise.”

    Ain’t that good news, man ain’t that news!

  16. I’ve got news for them. This terrestrial animal can adapt to climate change nonsense too. It’s called facts and a heightened BS detector.

  17. Better in german:

    Live = Leben / as in: real live

    Life = Jetzt / NOW as in Hollywood ‘action!’

  18. No reporter makes a ‘lifing’ from reporting –

    – he makes a LIVING from

    – reporting LIFE

  19. “Phytoplankton can increase the rate at which they take in carbon dioxide and release oxygen while in warmer water temperatures, a long-running experiment shows.”
    Chemical reactions can be accelerated by warming temperatures? Who knew? Only every chemist since Svante Arrhenius in 1889!

  20. From the article:
    “Phytoplankton use chlorophyll to capture sunlight, and photosynthesis to turn it into chemical energy. This means they are critical for reducing carbon dioxide in the atmosphere and for providing food for aquatic life.”

    Critical for reducing carbon dioxide in the atmosphere??? Atmospheric Carbon Dioxide is essential to all life as we know it, why is it critical to remove it?

    Extracting Carbon from atmospheric CO2 is critical, essential, paramount to Life. There is no photosynthesis without it.

    More atmospheric CO2 supports more Life. This article makes this exact point, but then accepts the premise that it’s beneficial to remove atmospheric CO2. A clear contradiction.

  21. “Experts had made predictions that that climate change would have negative effects on phytoplankton. But a new study shows green algae can adjust to warmer water temperatures.”

    Experts wrong; common sense prevails, but only after extensive and expensive studies by well-paid experts. Isn’t this a microcosm for everything that’s wrong with Climate Science?

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