Our Legacy - a Poisoned Planet
A new study1 Global cooling drove diversification and warming caused extinction among Carboniferous-Permian fusuline foraminifera, released 20 June, 2025 gives a high-resolution look at the deep history of biodiversity on this planet, being able to sort out time periods of less than 45,000 years during paleo history between 340 to 252 million years ago, by some exquisite data-wrangling. The authors, at the Nanjing University School of Earth Sciences and Engineering were studying mainly fusuline foraminifera, which form limestone deposits, which during those millions of years, underwent two major diversification bursts and four extinction crises.
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From a university press release:
“Notably, after the large-scale volcanic eruptions in the large Emeishan Igneous Province around 260 million years ago, large fusuline nearly disappeared. Later, during the end-Permian supervolcanic event about 252 million years ago, this vast lineage came to a complete evolutionary halt.”
“Alarmingly, the current rate of global warming caused by human activities far exceeds the warming rates associated with both the Emeishan basalts and the end-Permian volcanic events. Today's marine ecosystems may be facing a similar test of survival as once experienced by the fusuline.”
“This research not only unveils the critical role of climate change in driving biological evolution but also offers vital scientific insights for understanding biodiversity changes under today's global warming. Prof. Shen emphasizes, ‘Mitigating climate change and protecting ecosystems is an urgent task of our time.’”
From the Science Advances article:
Abstract
The fossil record provides the only direct evidence of changes in biodiversity over time. Patterns in more inclusive taxonomic levels (e.g., families and orders) often become more complex because of interactions between biological traits and environmental conditions across different evolutionary lineages. Using supercomputing and artificial intelligence algorithms, we analyzed a high-resolution global dataset of fusuline foraminifera—the most diverse marine fossil group from the Carboniferous to the Permian (~340 to 252 million years ago)—at an unprecedented temporal resolution of <45 thousand years. Our unbinned diversity reconstruction reveals unexpectedly simple diversity dynamics in this exceptionally well-preserved clade. We identify two (and likely a third) truncated exponential diversifications and four major diversity declines. During this interval, long-term cooling consistently promoted biodiversification, whereas warming events were closely linked to extinctions. These findings imply that the current rapid global warming, driven by anthropogenic CO2 emissions, represents a critical threat to modern ecosystems.
In summary, high-resolution fusuline diversity reveals two major episodes of biodiversification and four episodes of major diversity loss. Correlation with environmental variables suggests that fusuline macroevolution was primarily controlled by climatic shifts between icehouse and warmhouse conditions. Fusuline diversifications were interrupted by major climatic warming. These abrupt diversity losses might be linked to global warming derived from long-term massive degassing from increasingly intensified volcanism related to the continental reconfiguration during the Carboniferous and Permian. Thus, the diversity changes of the largest benthic foraminifera in marine ecosystems over 91.8 Myr provide insight into the evolution of modern marine ecosystems and their substantial simple dynamics under major climate shifts between icehouse and warmhouse stages. The current global warming from anthropogenic CO2 emissions has surpassed the amount input during the massive end-Permian mass extinction and is likely a great threat to modern marine ecosystems.
Some other sections:
The notably higher temporal resolution of our analysis—on the order of tens of thousands of years—allows us to resolve more detailed trends and events not apparent in previous work. Key findings include the following: slow initial diversification during the Visean-Serpukhovian (~343 to 323 Ma), with near-stasis in the Serpukhovian; exponential radiation beginning in the early Bashkirian (~321 Ma); a temporary Kasimovian diversity decline followed by recovery, culminating in an Asselian peak (~295 Ma); and prolonged Kungurian-Guadalupian (~278 to 266 Ma) diversification, interrupted by an end-Guadalupian decline before final end-Permian extinction. These patterns show notable correlations with contemporaneous climate proxy records, suggesting strong climatic controls on fusuline diversity dynamics.
Sustained global warming can damage or eliminate established ecological habitats, resulting in extinctions of benthic organisms that cannot adapt to rapidly changing environmental conditions. This warming may also disrupt the ability of equatorial regions to serve as key areas for biological recovery and renewal.
The persistent cooling during the Carboniferous and Permian fostered biodiversification, while the warming events caused biodiversity declines and mass extinctions.
For some definitions of these terms: Icehouse, 34 to 0 Ma (34 million years ago to recent human history), coolhouse as in LPIA- Late Paleozoic Ice Age, with CO2 and sea-surface temp similar to today, shifting to warmhouse over ~10 Myr: 293.57 to 283.58 Ma ago (5 to 10°C warmer than today as in Early Permian), hot house (greater than 10°C, as in early Triassic, the period following the End-Permian). Even with oxygen level about 50% higher than today in these past warmhouse/hothouse regimes, it was atmospheric CO2 levels and corresponding ocean acidification that sealed the fate of life in the end-Permian extinction. And we have exceeded that level already, presently over 430 ppm, see Mona Loa readings. And actually, we have enough CO2 in the atmosphere for 10°C of warming, but it is being ameliorated to about 2°C by aerosol cooling.
Yet there is no thought at all of reducing fossil fuel burning and even less thought of ending it. So where are we going with this? What is the end point before any action is taken? Shall we just sail up to 700 ppm like in the end-Permian and 95% of life expires and it takes 5 million years for new life forms to evolve? New subscribers would have missed my previous report on this topic in September, 2024: The Total Eclipse of the Earth. The consequences of the two fatal errors of humanity - creation of plastics and burning of fossil fuels will outlast us, and for plastics, the evil genie can’t be put back in the bottle, but we could drastically reduce fossil fuel usage. Look at that Mona Loa page and see how low it was in 1960. How hard was that?
Yet we have every government going all-in on fossil fuel promotion and the Big Business types claiming that we will be on fossil fuels for decades to come. Up to 700 ppm and beyond? And in Canada, we have the new Prime Minister, Carney, going all-in for new pipelines and minerals mining, in a new Shock Doctrine2. For another view of Carney’s “Shock Doctrine”, see that article at The Breach, and subscribe! A pipeline’s lifespan, from planning to end of life is about 50 years, taking us to 2075! And what will the CO2 level be by then? We’ll be cooked under that scenario.
And yet we have the geo-engineering morons hoping to put up some sort of “Sun shade” to reduce global warming. And what - keep on burning fuels? We are in an interglacial, the planet is warming, and no human activity can cool it. But the real problem, is the oceans! This is not about saving seaside cities, or people facing uncomfortable heat. Continuing this trajectory of fossil fuel usage WILL ruin the oceans and their recovery time is beyond imagination. People ask “what hope is there for the future?” Try to understand this - we have poisoned the future. We poisoned it with plastics for which there is no remedy - the only remedy is to never do something so stupid to this planet. The nanoplastics are corrupting every stage of all life forms. Meanwhile, we continue to poison it with CO2 emissions which will have drastic consequences - all for about 200 years of extravagant consumption. Total world financial debt is many times the annual actual productivity and the ecological debt has damaged every ecosystem, yet there continues to be more plans to further rip up our home planet as if it were a nearby resource planet. And from paleoclimate study it becomes apparent that a warming like what we have caused is not the main event. This warming triggers the BIG warming as ocean currents shut down, sea-bed methyl hydrates release methane and permafrost melts. BTW, the Atlantic current (AMOC) has been gradually slowing for the past century, see Kai-Yuan Li, et al.3 These events are out of human control - like the introduction of plastics, these emissions should have never started.
Do have a look at the Shu-Han Zhang et al. paper (see link at the top) to see the graphs. While reading that paper, I’m also looking at “Repeated occurrences of marine anoxia under high atmospheric O2 and icehouse conditions” by Jitao Chen4 et al., from June 23, 2025, in which you can see the maps of where ancient seabeds as presently located were situated originally. This is more excellent science from China, while American science is being dismantled. Here’s a part of that paper:
Significance
The overall well-oxygenated Phanerozoic ocean–atmosphere system experienced discrete periods of ocean anoxia that are closely associated with global carbon cycle perturbations under primarily greenhouse climate states. Here we document, through coupled U and C isotopic excursions and biogeochemical modeling, repeated occurrences of CO2 -induced marine anoxia at the 105 -y-scale during the highly oxygenated, but overall low CO2, deep glacial (310 to 290 Ma) of the penultimate icehouse. Our joint proxy-model inversion approach indicates moderate-scale seafloor anoxia (4 to 12%) that may have led to a pause or decline in marine biodiversity and reveals the potential for the development of widespread marine anoxia under CO2 concentrations not much different from today or projected for within this century.”
So that’s it - humans could choose a different legacy by ending these emissions to help save the oceans, otherwise all life suffers for long after humans are gone. Instead of building more megaprojects, more mines, more pipelines, more fossil fuels production, everyone needs to cut way back on consumption of everything. The entire human economy must shrink to small enough to crawl through the “Eye of the Needle” (the small door in the Needle Gate) to get into a smaller, sustainable future which can support life on this planet. Instead, all nations are being asked to “arm up” for the final conflagration. What fools these mortals be!5
1) - Shu-Han Zhang, Ying-Ying Zhao, Yu-Kun Shi, Qiang Fang, Xiang-Dong Wang, Jun-Xuan Fan, Yi-Chun Zhang, Dong-Xun Yuan, Yue Wang, Fei-Fei Zhang, Huai-Chun Wu, Douglas H. Erwin, Charles R. Marshall, And Shu-Zhong Shen, 2025, Global cooling drove diversification and warming caused extinction among Carboniferous-Permian fusuline foraminifera. Science Advances, 20 Jun 2025, Vol 11, Issue 25, https://doi.org/10.1126/sciadv.adv2549
2) - See the book: Shock Doctrine - The Rise of Disaster Capitalism, by Naomi Klein.
3) - Kai-Yuan Li et al, Weakened Atlantic Meridional Overturning Circulation causes the historical North Atlantic Warming Hole, Communications Earth & Environment (2025). https://dx.doi.org/10.1038/s43247-025-02403-0
4) - Jitao Chen, Shihan Li, Shuang Zhang, Terry Isson, Tais W. Dahl, Noah J. Planavsky, Feifei Zhang, Xiang-dong Wang, Shu-zhong Shen, and Isabel P. Montañez, 2025 "Repeated occurrences of marine anoxia under high atmospheric O2 and icehouse conditions" PNAS 122 (26) e2420505122, https://doi.org/10.1073/pnas.2420505122
5) - From a line delivered by Puck to his king in “A Midsummer Night’s Dream” by William Shakespeare, commenting on the folly of the human beings who have come into his forest. And here we are at midsummer, commenting on the fools who are abusing this planet.