Science Snippets: Ancient Trees and Chinese Dynasty Reveal Climate Change

Draft script:

I have mentioned many times in this space the evidence underlying anthropogenic climate change. More recently, with the assistance of Dr. Niall Shephard, I have begun exploring climate change within the construct of deep time, going back many thousands of years. This video addresses climate change and its impacts within the context of deep time.

First, I’ll go back a few thousand years, using ancient trees. An article at Daily Galaxy published on 9 March 2025 is titled Ancient Trees Frozen for 6,000 Years Emerge From Ice. The subhead reads “Buried beneath the ice for nearly 6,000 years, a lost forest of ancient trees has just been uncovered in the Rocky Mountains—and what it reveals about Earth’s past and future is both fascinating and alarming.”

I suspect you can imagine what is fascinating and what is alarming. The opening paragraph clarifies: “A recent discovery in the Rocky Mountains has given scientists an extraordinary look into the past, but it comes with an unsettling reminder of the effects of climate change. A 5,900-year-old forest was found preserved under ice at Wyoming’s Beartooth Plateau, offering valuable insight into ancient ecosystems. This remarkable find, detailed in a study published in the Proceedings of the National Academy of Sciences, underscores the impact of warming temperatures. The forest was uncovered as ice patches melted, further highlighting the growing threat of rising global temperatures to high-elevation ecosystems.”

As explained in the article at Daily Galaxy, the results of this study are based on 30 well-preserved whitebark pine trees that were 5,440 to 5,950 years old. The trees were discovered 180 meters above the current tree line, indicating that temperatures at that time were warm enough to support trees at higher elevations than today. As global temperatures continue to rise, trees are expected to continue their march upward. According to the misinformed article at Daily Galaxy, the attendant shifts in the environment “could disrupt species reliant on alpine conditions.”

We should be so lucky. Instead of disrupting “species reliant on alpine conditions,” the current rate of environmental change is disrupting habitat for all life on Earth. The ongoing Mass Extinction Event is driving a rate of extinction unparalleled in planetary history. If only we were to be concerned just about tree lines.

Next up, Chinese dynastic history has been revealed by climate change. According to the headline of an article at Phys.Org on 11 February 2025, Ancient tree rings uncover climate’s impact on Chinese dynastic history. Here’s the lede: “A study tracking rainfall patterns over thousands of years has found that more arid periods coincided with ages of dynastic turmoil in China—highlighting a historical link between climate stress and social unrest.” In this case, the climate was reconstructed for the last 3,476 years, slightly less than the research reported in Daily Galaxy.

The article at Phys.Org refers to a peer-reviewed, open-access paper in Nature Communications. This paper was published 3 February 2025 and titled Recent centennial drought on the Tibetan Plateau is outstanding within the past 3500 years. The peer-reviewed paper was created by 33 scholars. The Abstract includes abundant, relevant information: “Given growing concerns about global climate change, it is critical to understand both historical and current shifts in the hydroclimate, particularly in regions critically entwined with global circulation. The Tibetan Plateau, the Earth’s largest and highest plateau, is a nexus for global atmospheric processes, significantly influencing East Asian hydroclimate dynamics through the synergy of the Asian Monsoon and the Westerlies. Yet, understanding historical and recent hydroclimate fluctuations and their wide-ranging ecological and societal consequences remains challenging due to short instrumental observations and partly ambiguous proxy reconstructions. Here, we present a precisely-dated 3476-year precipitation reconstruction derived from tree-ring … data on the Tibetan Plateau, …. Our findings reveal that the 20^th century drought extremes are severe within the past three millennia, and likely linked to the weakening of both the Asian Monsoon and Westerlies due to anthropogenic aerosol emissions. Additionally, our analyses identified three distinct stages (110 BC–AD 280, AD 330–770 and AD 950–1300) characterized by shifts toward arid hydroclimate conditions, corresponding to significant social unrest and dynasty collapses, which underscores the potential societal impacts of severe hydroclimatic shifts.”

This is the first time I have seen such compelling evidence supporting the idea of regime changes as a result of climate change. I strongly suspect we will soon experience additional evidence of the strong link between climate change and social unrest. Because Earth is amid the most abrupt rate of change in planetary history, and also because this environmental change is irreversible, I cannot imagine we will escape social unrest in the years to come. That the current presidential administration seems to think social unrest is a good idea is not helping, and will not help in the near future.

As I have mentioned previously in this space, Popular Mechanics has been producing relevant articles about anthropogenic climate change. These articles are timely and strongly supported by evidence. Popular Mechanics has done it again with an article published 14 March 2025 and titled All Life on Earth Comes From One Single Ancestor. And It’s So Much Older Than We Thought. The subhead is “Scientists have pushed back LUCA’s origin by hundreds of millions of years.” LUCA is explained in the first of three bullet points that begin the article:

• “All life on Earth can be traced back to a Last Universal Common Ancestor, or LUCA.”

• “A study suggests that this organism likely lived on Earth only 400 million years after its formation.”

• “Further analysis also shows that this life form likely sported an early immune system, which means it was probably fighting off viruses.”

This latter point is surprising. Only 400 million years after Earth formed, our earliest known ancestor was already fighting off primordial viruses. Doing so indicates our earliest known ancestor was a relatively complex organism.

The article in Popular Mechanics refers to a peer-reviewed, open-access paper in Nature Ecology & Evolution. Created by 19 scholars and published 12 July 2024, the paper is titled The nature of the last universal common ancestor and its impact on the early Earth system. The Abstract includes this information: “The nature of the last universal common ancestor (LUCA), its age and its impact on the Earth system have been the subject of vigorous debate across diverse disciplines, often based on disparate data and methods. Age estimates for LUCA are usually based on the fossil record, varying with every reinterpretation. The nature of LUCA’s metabolism has proven equally contentious, with some attributing all core metabolisms to LUCA, whereas others reconstruct a simpler life form dependent on geochemistry. … Although LUCA is sometimes perceived as living in isolation, we infer LUCA to have been part of an established ecological system. The metabolism of LUCA would have provided a niche for other microbial community members and hydrogen recycling by atmospheric photochemistry could have supported a modestly productive early ecosystem.”

The evidence continues to accumulate: We are one. Even our common ancestor from billions of years ago was “part of an established ecological system.” It was also part of “a modestly productive early ecosystem.” This latter attribute indicates contemporary members of Homo sapiens have much to learn from our earliest known ancestor.