Category: Science Books

Four Billion Years and Counting…

Four Billion Years and Counting: Canada’s Geological Heritage. Produced by the Canadian Federation of Earth Sciences, by seven editors and dozens of authors. 2014.

November-December, 2024.

I am reading this with CJS. It is a nice overview of regional geology, and it is nice that all the examples come from Canada, and at least some of the discussion is relevant to Minnesota Geology. The book is notable for its beautifully done pictures and diagrams.

The first part of the book, Foundations, is an introduction to general geological concepts. For CJS and I this will be largely review. Here I will preterit any summary, and simply list some of the points that stood out because they filled in a gap, or provided a different perspective.

FOUNDATIONS

C1: Miscellaneous Points

  • Polygonal jointing occurs when basalt flows stop moving before they cool.
  • Granitic magma forms at 600-900°, sometimes with water contributing to lowering the melting point, where silica minerals tend to melt, but more magic minerals remain solid. The melt tends to move upward, either because it is less dense than surrounding rock or because of tectonic pressures. As it forms a mass, chunks of surrounding “country rock” fall into it in a process called “stoping,” making the melt more silicacious and also persisting in solid chunks that will eventually become xenoliths.
  • Ripples (and their large scale cousins, dunes) are straight and symmetric if they are formed by currents moving back and forth, or curved if they are created by a unidirectional flow.
  • Mud cracks form as a result of repeated drying and wetting, as occurs in mudflats with seasonal rain, or intertidal areas.
  • A seam of coal that is a meter thick was originally 5-10 meters thick and took on the order of 2500 years to accumulate.
  • Paleosols, fossil soil surfaces/horizons, are generally rock-like with a characteristic disrupted knobby appearance.
  • Metamorphic rocks develop cleavage planes perpendicular to the direction force or pressure is being applied; metaphorphic rocks split along cleavage planes, not their original bedding surfaces.
  • Schist has a lot of mica; gneiss has little. Both are coarsely crystalline and so highly-altered that it is difficult to tell what the source rock was. The light and dark banding in gneiss is the result of recrystallization, and has nothing to do with the original bedding plane.

At lower metamorphic grades, platy crystals of chlorite and mica are common. As higher metamorphic grades are reached, minerals such as garnet, staurolite, and sillimanite may form. Such high-grade metamorphic rocks form at depths of 15 to 25 kilometres within the crust. If pressure (usually the result of deep burial) is a major factor during metamorphism, minerals such as kyanite and glaucophane may grow. The blue colour of glaucophane gives rise to the name blueschist, a rock formed under conditions of low temperature and high pressure.

Igneous rocks also show interesting metamorphic changes.When basalt is metamorphosed at low pressures and temperatures, some of its constituent minerals convert to the green minerals chlorite, actinolite, and epidote, producing a type of rock called greenstone or greenschist. At higher metamorphic grades, greenstone becomes amphibolite, a dark green to black rock made up of interlocking amphibole crystals.

C2: Miscellaneous Points

  • Reverse and thrust faults are different. They are created by the same array of forces, but reverse faults are steeper (closer to vertical) than thrust faults. …The text doesn’t say where the line is between them…
  • Fault breccia. Rock formed of a jumbled mix of sharp rock fragments embedded in lithified rock flour.
  • Nice review of minerals: pages 19-21.
  • The Greenville orogen underlies Quebec, the midwest US, and stretches into mexico.

All modern oceans contain areas where the lithosphere is thicker than regular oceanic litho-sphere. These areas include island arcs, oceanic plateaus perhaps bearing atolls, and isolated fragments of continental lithosphere such as present-day Madagascar. If subduction continues and these within-ocean features are swept toward the continent, they will ultimately collide with it. Because high-standing islands or plateaus are more buoyant than regular oceanic lithosphere, they will be scraped off the sub-ducting plate and will stick, or accrete, to the overriding plate rather than be subducted. Many mountain belts contain remnants of such former within-ocean features; such remnants are called terranes (a term not to be confused with terrain, which denotes topography). Terranes thus have a variety of origins: they may be continental fragments (microcontinents); former island arcs; or former pieces of thickened oceanic lithosphere such as Hawaii may become if it is accreted to a continent. Many terranes are a mixture of these elements. The convergence and collision of terranes with continental margins commonly leads to the rise of mountains.

Remnants of former deep oceanic lithosphere can be preserved within an ancient mountain system. Such remnants are known as ophiolite suites or ophiolites…

  • Rift Shoulder Highlands are mountains produced as a side effect of continental rifting — when the floor of the rift is bulging upwards.
  • Basins. Fore arc basins are in front of island arcs; back arc basins are behind them. Fore land basins can form on continents, due to the weight of accretionary material pushing down that part of the continental plate. …Is the Owens Valley in California such a basin?
  • The next supercontinent has already been named: Amasia.

C3: Miscellaneous Points

C4: Miscellaneous Points

  • xxx

Part II: The Evolution of Canada

Cx: xxxx

  • xxx

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Through the Language Glass

by Guy Deutscher

October 2024

This is an excellent book; interesting well-documented science, and some beautiful and erudite writing as well. The basic argument — that grammar determines what must be specified, rather than what can be specified, and in that manner instills certain habits of mind that effect how people see the world — seems correct, if not quite living up to the subtitle of the book: Why the World Looks Different in Other Languages.

Perhaps the most interesting and fun part of the book was to be introduced to languages that work very differently from English: The Mates language (in Peru) that requires speakers to specify whether the fact they report is based on personal observation, indirect evidence, or hearsay; and the Australian language that has no egocentric prepositions, but requires all positional information to be reported in terms of the cardinal directions, thus requiring their speakers to always be oriented.

This book was a pleasure to read. I plan to seek out other work by this writer. 

Contents

Front Matter

On whether languages reflect the characteristics of their speakers, he writes:

Many a dinner table conversation is embellished by such vignettes, for few subjects lend themselves more readily to disquisition than the character of different languages and their speakers. And yet should these lofty observations be carried away from the conviviality of the dining room to the chill of the study, they would quickly collapse like a soufflé of airy anecdote-at best amusing and meaningless, at worst bigoted and absurd.

— p. 2

The basic argument of the book is this:

The effects that have emerged from recent research, however, are far more down to earth. They are to do with the habits of mind that language can instill on the ground level of thought: on memory, attention, perception, and associations. And while these effects may be less wild than those flaunted in the past, we shall see that some of them are no less striking for all that.

I think it is correct, but that the subtitle of the book – Why the World Looks Different in Other Languages – is a bit of an exaggeration.

C1-5: <Reprise of history and status of color terms>

C1: Naming the Rainbow

This chapter reprises now-unknown work by William Gladstone (now remembered as an English prime minister) on Homer and his writings, and focuses in on particular on one chapter in Gladstone’s monumental 3,000 page work: a chapter on Homer’s use of color terms.

Gladstone’s scrutiny of the Iliad and the Odyssey revealed that there is something awry about Homer’s descriptions of color, and the conclusions Gladstone draws from his discovery are so radical and so bewildering that his contemporaries are entirely unable to digest them and largely dismiss them out of hand. But before long, Gladstone’s conundrum will launch a thousand ships of learning, have a profound effect on the development of at least three academic disciplines, and trigger a war over the control of language between nature and culture that after 150 years shows no sign of abating.

Gladstone notes that Homer uses color terms in odd ways — the famous “wine dark sea” (really “wine-looking” sea) being just one example.

Mostly Homer, as well as other Greek authors of the period, use color very little in their descriptions: mostly they use black or white; terms for colors are used infrequently and inconsistently. For example, the only other use of “wine-looking” is to describe the color of oxen.

Gladstone’s fourth point is the vast predominance of the “most crude and elemental forms of color”-black and white-over every other. He counts that Homer uses the adjective melas (black) about 170 times in the poems, and this does not even include instances of the corresponding verb “to grow black,” as when the sea is described as “black-ening beneath the ripple of the West Wind that is newly risen.” Words meaning “white” appear around 100 times. In contrast to this abun-dance, the word eruthros (red) appears thirteen times, xanthos (yellow) is hardly found ten times, ioeis (violet) six times, and other colors even less often.

C6: Crying Whorf

This chapter describes the origin, rise and fall of linguistic relativity. Sapir is depicted as respectable but making over-stated claims; Whorf comes across as a charlatan, for example, making claims to have deeply studied Hopi, when he only had access to a single informant in New York – and making broad claims that are entirely wrong (e.g. that the Hopi language does not have a future tense). 

Deutscher traces the origin of linguistic relativity to Wilhelm von Humboldt in 1799,  whose “linguistic road to Damascus led through the Pyrennes.” Deutscher encountered the Basque language, and found that it was radically different from the languages linguists tended to study. He then sought out other ‘more exotic’ languages, which he found by going to the Vatican library and studying the notes of Jesuit missionaries to South and Central America: “…Humboldt was barely scratching the surface. But the dim ray of light that shown from his materials felt dazzling nonetheless because of the utter darkness in which he and his contemporaries had languished.” p. 135 Although Humboldt’s ideas led to linguistic relativity, it should be noted that he had a much more nuanced and correct view: In principle, any language may express any idea; the real differences among languages are not what they are able to express but in “what it encourages and stimulates its speakers to do from its own inner force.” But this view was not carried forward, and instead: “The Humboldtian ideas now underwent a process of rapid fermentation, and as the spirit of the new theory grew more powerful, the rhetoric became less sober. ”

All that said, Deutscher argues it is a mistake to dismiss the idea that language has no influence over thought. But rather than taking the strong case the language constrains thought, he instead argues the habits of language may lead to habits of mind. In the case of the influence of language, and refers to the idea that Boas introduces and that Jakobson crystalized into a maxim: “Languages differ in what they must convey, and not in what they may convey.”

Phrases I like

“…has still the power to disturb our hearts.” [Sapir, referring to Homer, Ovid, etc.] p. 129

“[His] linguistic road to Damascus led through the Pyrennes.” p. 134

“…Humboldt was barely scratching the surface. But the dim ray of light that shown from his materials felt dazzling nonetheless because of the utter darkness in which he and his contemporaries had languished.” p. 135

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w/CJS: Best Science & Nature Writing, 2022

April 2024 on…

Reading The Best American Science and Nature Writing , 2022 (ed. Ayaba Elizabeth Johnson) with CJS.

So far, as of May 2024, this is a very enjoyable read. I particularly appreciate the efforts of the editor to create a nice progression of topics, giving what is essentially an eclectic sampling of articles a higher level narrative.

September 2024: Nearing the end; still an enjoyable read.

Favorites

After finishing the book, here are my favorites

Top Five Six

  • C2 – What Slime Knows. Really gave me a new view of slime molds. I hadn’t realized the degree of intelligence a seemingly simple colonial organism can possess. Offers a counter-narrative to the usual ideas about what is necessary for intelligence.
  • !! C7- Rising Groundwater. This is the biggest eye-opener in the book, at least for me. While sea level rise will have very obvious impacts on costal regions, this makes the point that sea water will also cause a rise in ground water and, with or without infiltrating it, will cause a lot of problems for a lot more people than are effected directly by sea level rise. Think corroding water and gas pipes, malfunctioning sewage systems, and failing electical systems. This is one I’ll tell other people about.
  • C15: Poisoned—Part I: The Factory. Not a pleasant story. Talks about working conditions in a battery recycling factory, the horrible degree of exposure to lead, and the toll it takes on the workers. Shocking for two reasons: one is that the company behind this is based in Minnesota, and is in theory doing good things (recycling lead from batteries); second, that the industry and factories are regulated, but that in spite of that conditions are horrible.
  • !! C25 – Why Combining Farms & Solar Panels Could Transform How We Produce Both Food and Energy. A hopeful and plausible tale about how we can do better quite easily. A win-win. Perspective shifting and positive. I’ll mention this to others.
  • : – ) C28 – Beavers Are Firefighters Who Work for Free (Sierra) A perspective shifting article on role beavers can play in making land more resistant to wildfires, and also points out that the autonomy of tribes can allow them to take the forefront in experimenting with more sustainable approaches to environmental problems.
  • : – ) C32 – A River Reawakened (Orion). Not a perspective shifter, but just a very pleasant positive piece on what happens when a river is undammed, the problems that need to be addressed, and the rapidity of recovery. This was going to be an honorable mention, but I liked it too much!

Honorable Mentions

Continue reading w/CJS: Best Science & Nature Writing, 2022

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w/RB: The Master Builder: How the New Science of the Cell is Rewriting the Story of Life, Alfonso Martinez Arias

* The Master Builder: How the New Science of the Cell is Rewriting the Story of Life, Alfonso Martinez Arias, 2023

March 2023…

I am reading this book with RB, a chapter or two at a time. My first impression is that it is going to be a great read. It has interesting and new-to-me science straight from a scientist who has spent his career studying this area, and it is well written too.

The premise of the book is that DNA gets too much credit for its role in shaping organisms, and that it is also important to pay attention to the ways in which cells carry out the ‘instructions’ of DNA. Unlike DNA, cells can respond to their environment, sense ambient conditions at the cellular level, and respond to distance and orientation. Quite a number of things that we would presume would be determined by genetics — everything from finger prints and retinal patterns to birth defects, propensity to diseases, and the location of organs in the human body — are determined by cells rather than DNA.

Continue reading w/RB: The Master Builder: How the New Science of the Cell is Rewriting the Story of Life, Alfonso Martinez Arias

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LS: A Wilder Time,* William E. Glassley

*A Wilder Time: Notes from a Geologist at the Edge of the Greenland Ice. William E. Grassley, 2018.

A lyrical book that provides an account of a geologic expedition to gather evidence for a 1.8 Ga collision between continents that resulted in a series of shear zones in western Greenland. Also important for providing evidence that plate tectonics has been going on for a long time, something that has been contested. Content is quite interesting, but I also appreciate it for its lyrical writing about landscape and geology, which is this focus of my “LS” project.

Continue reading LS: A Wilder Time,* William E. Glassley

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EP#14: 2023 Best Science & Nature Writing–Overview

* The Best American Science and Nature Writing of 2023 (ed. Carl Zimmer)

February – March 2024

CT and I selected this book to continue our essay project. However, after reading the first three pieces, we have reconsidered. Although the articles are interesting, they are not what either of would call essays. It’s really journalism, with the focus on ideas. The prose is generally clear and workman like, but as yet we have not encountered any writing that makes us pause to savor the phrase. We intend to look through the book, and — by paying attention to where the piece was originally published – see if we can come up with more essay-like pieces. However, we both suspect, that the book will not past muster vis a vis our project, and that we will move on to something else following our next meeting.

Continue reading EP#14: 2023 Best Science & Nature Writing–Overview

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LS: Land Above the Trees: A Guide to American Alpine Tundra, Ann Zwinger & Beatrice E. Willard

February 2024…

This book was recommended in Kim Stanley Robinson’s The High Sierra: A Love Story, as a good guide to the ecology and botany of the Sierra Nevada (and the upper portions of other North American ranges). And, indeed, it is beautifully written with a narrative style in which the reader moves through landscapes with the authors, looking at this and that, in contrast to what I had expected would be more of a catalog or encyclopedic approach. The book is divided into two principle parts: part 1 examines elements of ‘above the trees’ ecosystems, like fellfields or krumholtz; part 2 looks at particular North American tundra ecosystems, with one chapter being on the Sierra Nevada.

Continue reading LS: Land Above the Trees: A Guide to American Alpine Tundra, Ann Zwinger & Beatrice E. Willard

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w/CS: Gulp: Adventures on the Alimentary Canal, Mary Roach

January-February 2024

Gulp: Adventures on the Alimentary Canal, Mary Roach, 2022. I am reading the with CS. Mary Roach is a popular science writer who has developed a ‘brand’ of doing popular science books with toungue-in-cheek titles like Gulp, Stiff, Bonk, and so forth.

My impression after the first two chapters is that it will be a fun, fairly light read. She is very good at tossing in the amusing descriptive phrase.

Continue reading w/CS: Gulp: Adventures on the Alimentary Canal, Mary Roach

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EP #`13: Awakenings, Oliver Sacks

January 2024

Entry 13 in the Essays Project with CT; this is the seventh book we’ve read by Oliver Sacks. This is the book that, with the help of a documentary and then movie, transformed him into something of a celebrity. It is an account of the experience of ‘awakening’ patients with Parkinson’s induced by Encephalitis Lethargia by administering L-Dopa, their experiences of returning to a sort of normal life, and then their declines due to the follow-on negative effects of L-Dopa.

Continue reading EP #`13: Awakenings, Oliver Sacks

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LS*–The High Sierra: A Love Story, Kim Stanley Robinson

November 2023

The High Sierra: A Love Story, by Kim Stanely Robinson. 2022.

* I was reading this for other reasons, but nevertheless it fits well into my project to read essays that focus on landscape and natural history.

TL;DR: I love this book. But it is not for everyone. On the other hand, it is organized in such a way that readers interested in particular topics — geology, history, etc. – could skip through the book attending to one or a few themes that interest them. It has great pictures, too.

#

I’m a big fan of KSR, and think it likely that I’ve read everything he’s written, although it is possible that that omits a few early science fiction novels that were retroactively published after he became better known. I like the complex characters he develops, the intensely developed worlds he portrays, and especially his attention to geology, climate, economics, politics, and the role of large institutions – themes that are uncommon in much science fiction. Also unusual is that he sometimes ventures beyond the borders of SF, as with his novel Years of Rice and Salt, and especially with this book, which is multi-threaded work the interweaves memoir, geology, natural history and history.

Continue reading LS*–The High Sierra: A Love Story, Kim Stanley Robinson

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w/CS: Elixir: A History of Water and Humankind*, Brian Fagan

November 2023…

*Elixir: A History of Water and Humankind, Brian Fagan. Reading with CJS.

Comment after finishing seven chapters:
There is interesting material here, and I am happy to be reading it. However, the writing is not grea: it is difficult to follow if you are really trying to get a deep sense of what is going on.

  • The same date is sometimes referred to as 4,000 BCE, 6,000 years ago, or a millennia after another event. I can do the math, but pausing to do so drops me out of the flow of the text.
  • The maps helpfully included in the chapters lack many of the places referred to in the text: Where are the Taurus mountains? Are they the same as the mountains near Cudi Dag (not shown on the map either). Clearly, neither writer nor editors ever tried referring to the associated map…
  • Places are also referred to with different names: The Lands of Enlil; Southern Mesopotamia; the lands to the south of modern-day Bagdad; the Fertile Crescent refer, I think, to the same area. But it is difficult to be sure.
  • Often it is unclear what the relationship between sequential examples are — are they supposed to reinforce one another, or complement one another, or are they being presented for some other reason? Sign-posting would be really helpful.

Preface

The three themes of this book are (1) gravity and its fundamental impact on the flow of water; (2) the relationship between ritual and water management; and (3) sustainability. One point the book will take up is the way in which the invention of the mechanical pump transformed the mining and movement of water.

The book takes an anthropological perspective, closely examining the relationships between water technologies and human usage and management practices, and looking at the role rituals play. It looks at both historical examples — even reaching into the deep past where the primary source of information is archeological work — and present day examples. And of course the book addresses the ongoing crisis in water sourcing and distribution, and the question of sustainability.

Continue reading w/CS: Elixir: A History of Water and Humankind*, Brian Fagan

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EP#12: The Mind’s Eye, Oliver Sacks

November-December 2023

Entry 12 in the Essays Project with CT; and this is the sixth book we’ve read by Oliver Sacks. Here we take up the neurological case account essays for which he is best known, after reading his two autobiographies, and other writings ranging from general essays to an account of his travels in Oaxaca. This book, published in 2010, explores cases in which people have lost visual abilities that we all take for granted – not so much blindness (although maybe there will be some essays on that), but rather the consequences of some of the many ways in which the complex and intertwined elements of the visual processing system may be disrupted.

Continue reading EP#12: The Mind’s Eye, Oliver Sacks

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w/CS: Islands of Abandonment: Nature Rebounding in the Post-human Landscape, by Cal Flyn

September 2023

Islands of Abandonment: Nature Rebounding in the Post-human Landscape, by Cal Flynn, 2021.* This book looks at how nature — fungi, plants, animals – are re-colonize landscapes that have been destroyed and abandoned by humans. Examples include massive slag piles, nuclear test grounds, etc. It examines both how primary succession occurs in unpromising circumstances, and how the absence of human presence facilitates re-wilding. In the introduction, the author notes that we are now in the midst of a vast self-directed experiment in re-wilding, driven in part by the concentration of people in cities (and a soon-to-be-decreasing population), and in part by the depletion of non-sustainable natural resources that leave ‘waste lands’ behind.

Post-reading comment: There are three or four chapters in the book that are great, and really align with the aims laid out above. Unfortunately, more of the chapters, particularly as one progresses in the book, are more in the line of what I would call disaster tourism: lyrical descriptions of degraded environments and terrible situations, with little or no mention of how the ecosystem has adapted or not.

* Reading with CJS, fall of 2023

Continue reading w/CS: Islands of Abandonment: Nature Rebounding in the Post-human Landscape, by Cal Flyn

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w/RB: An Immense World: : How Animal Senses Reveal the World Around Us, Ed Yong

An Immense World: How Animal Senses Reveal the World Around Us, Ed Yong, 2022.

Overall, a good book. Yong writes well, and sometimes has very nice turns of phrase, though I’d say his gift is more for clarity and content than lyricism. The downsides of the book — small ones but nevertheless there — is that he often doesn’t go as deeply into the mechanisms and neurophysiology of sensing as I would like. It is also the case that one gets a bit of whiplash from looking first at this organism, and then at that, and then at that — but I don’t see how that could have been avoided in this sort of book.

To summarize briefly and incompletely, here are some of the points I found most interesting:

  • What we think of as a single sense (e.g., vision) can be quite complex. All of the following can be separate: distinguishing light from dark areas; color vision (and bi- tri- and tetra-achromatism); ability to see polarized and/or UC and/or infrared light; and more.
  • Also, the same sense can be configured and deployed in different ways: the shape of an organism’s visual field is tightly bound with its role in the food web; an organism may have one, two or multiple eyes, and may be able to move them independently; and so on.
  • Some senses seem easy to evolve, in that they have been independently evolved at many different points in time. And then lost, and then re-evolved.

April 2023 – February 2024

Introduction

The book begins with a fanciful description of a room with different creatures in it, including a human, a robin, an elephant, a spider, and so on. It uses this to make the point that the different creatures, although all in the same room, have radically different impressions of the room and its occupants. What is evident to one is invisible to another. An organism’s very particular view of its environment – is referred to as its umveldt, coined by Jacob Uexkull in 1909.

Continue reading w/RB: An Immense World: : How Animal Senses Reveal the World Around Us, Ed Yong

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w/CS: The Ends of the World, Peter Brannon

The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and our Quest to Understand Earth’s Past Mass Extinctions. Peter Brannon. 2017

April – June 2023

Summary of Periods and Mass Extinctions

  • Edicarian: 635-538. First appearance of wide-spread multi-cellular organisms in ocean: Soft-bodied microbial organisms forming mats and other structures, and free-floating filter feeders.
  • End-Edicarian extinction: ~448. 86% species went extinct.* Possibly due to advent of burrowing organisms that disrupted largely sessile ecosystem. Not an official mass extinction because of a very incomplete fossil record.
  • Cambrian: 538-485. Warm shallow seas flank margins of several continental remnants of the breakup of the supercontinent Pannotia. In ocean there is the advent of hard-bodied complex organisms, and subsequent explosion of diversity into all phyla known today. The land bare except for microbial crust; arthropods and mollusks begin to adapt to life on land towards the end of this period.
  • Ordovician: 485 – 433. High CO2 levels and continents inundated with vast shallow seas jammed with life: brachiopods; trilobites; cephalopods; eurypterids; grapholites; and jawless fish. Many isolated continents and islands, with continents at south pole and a global sea occupying most of the northern hemisphere. First spores of land plants (fungi and simple plants) at 467Ma, with their spread possibly releasing phosphorous into the ocean stimulating algal blooms and CO2 sequestration.
  • End-Ordovician extinction:~345 Ma. 75% species went extinct.* Major ice age, likely precipitated by biogenic CO2 depletion, followed by a whip-lash of warming.
  • Silurian: 443-419. Gondwanaland and island chains provide diversity of environments; in the ocean early fish diversify into jawed and bony fish. Terrestrial life expands in the Silurian-Devonian Terrestrial Revolution: vascular plants emerge from more primitive land plants, and three groups of arthropods (myriapods, arachnids and hexapods) became fully terrestrialized.
  • Devonian: 419-359. Gondwana supercontinent in the south, Siberia to the north, and Laurussia to the east. Free-sporing vascular plants form extensive forests (Archaeopteris); by the middle of the Devonian several groups have evolved leaves and true roots; by the end the first seed-bearing plants appear.
  • Late-Devonian extinction event: ~250 Ma. 96% species went extinct.* Two major extinction pulses, and many smaller pulses. One theory is that it is due to the release of nutrients by the punctuated spread of land plants as they developed vascular systems with leaves and roots, and seeds.
  • Carboniferous: 359-299. Age of amphibians — also first appearance of amniotes from which both reptiles and mammals came. Vast rainforests covered the land, and insects diversified. The latter part of the Carboniferous experienced glaciations, low sea level, and mountain building as the continents collided to form Pangaea. A minor marine and terrestrial extinction event, the Carboniferous rainforest collapse, occurred at the end of the period, caused by climate change
  • Permian: 299-251. On land: The Carboniferous rainforest collapse left behind vast regions of desert in the continental interior. Amniotes, which could better cope with the conditions, diversified into the synapsids (the ancestors of mammals which came to dominate the Permian) and the sauropsids (reptiles). . In the ocean fish diversify with placoderms dominating almost every known aquatic environment, alongside coeleocanths, with sharks and bony fishes on the sidelines.
  • End-Permian extinction: 251.9 Ma. 80% of species went extinct.* The Siberian Traps were created at 252 Ma and also interacted with the Tunguska sedimentary basin filled with carbonates, shale, coal and salt in layers up to 12 Km thick; it is the worlds largest coal basin. When the magma intersected the basin, it caught fire, detonated in multiple places, and released vast about of CO2 and methane, on top of the CO2 produced by the eruption contributing to global warming and ocean acidification and anoxia. Other chemicals produced by the incineration of the Tunguska basin contents may have destroyed the ozone layer.
  • Triassic: 252-201. Brannen argues for a long 5 – 10 million year recovery, but that is disputed. The ancestors of crodcodiles dominated the Triassic; ancestors of dinosaurs and first true mammals appear, but were not dominant. The global climate during the Triassic was mostly hot and dry. Pangea had deserts spanning much of its interior until ita began to gradually rift into Laurasia and Gondwana to the south. In line with this the climate shifted from hot and dry to more humid, with a massive rainfall event called the Carnian Pluvial Event that lasted a million years.
  • End Triassic Extinction: 200 Ma. 80% of species went extinct.* Volcanism from the rifting of Pangea produced flood basalt that covered more than 4 million square miles. The CO2 concentration doubled or tripled, raising the already warm temperatures by at least 3 ° C. The final extinction pulse was fast: on the order of 20,000 years.
  • Jurassic: 201.4 – 145. Gondwana begins to rift. Climate warm and humid.
  • Cretaceous: 145 – 66. Gondwana completes rifting and by the end of the period today’s continents are recognizable, but with shallow inland seas in North America and Africa and between Greenland and Norway.
  • End Cretaceous Extinction: xxx. 76% of species went extinct.* Most likely some combination of the eruption of the Siberian Traps and the Chixtulub impact lead to global warming and an extended period of darkness. Almost all large animals eliminated, including all dinosaurs excerpt ancestors of birds.
  • Percent of species that went extinct, for any one event, vary considerably among sources. These numbers are better read as an indicator of relative severity.
Continue reading w/CS: The Ends of the World, Peter Brannon

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w/CS: The Tangled Tree: A Radical New History of Life, David Quammen

January – April 2023

The Tangled Tree: A Radical New History of Life, David Quammen, 2018. These are my chapter by chapter notes. Besides having very good reviews and being by a well-regarded author, this book got a (rare) very high rating from Reid Priedhorsky…

Read this with CS.

Continue reading w/CS: The Tangled Tree: A Radical New History of Life, David Quammen

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w/KC: Metaphors We Live By, Lakoff and Johnson, 1980

January 2023

The Book: Metaphors We Live By, George Lakoff and Mark Johnson, 1980

Prelude

Written in 1980, this book challenged what was then the conventional view of metaphor – in psychology, linguistics and philosophy – as a sort of minor, poetical flourish that had little to no role in the how people understand language. In sharp contrast, MWLB argued metaphor is central to not only the way humans understand language, but how they conceptualize and experience the world. The suggest that most metaphor is systematic, in that there are root metaphors which structure the way abstract topics are conceptualized. L&J distinguish among three types of metaphoriic systems: Structural (ARGUMENT IS WAR); Orientational (MORE IS UP); and Ontological (IDEAS ARE OBJECTS). They also not that metonymy, while it is referential rather than metaphorical, is systematic in the same way metaphor is. 

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w/CS: Alien Oceans: : The Search for Life in the Depths of Space, Kevin Peter Hand

25 October 2022 and on…

CS and I are reading Alien Oceans: The Search for Life in the Depths of Space, by Kevin Peter Hand. These are my chapter by chapter notes. We are now through chapter 7, and are enjoying it. It does not assume much science background, and thus spends a lot of time explaining things that we are familiar with (e.g. why water’s hydrogen bonds cause water ice to be lower density than liquid water). But it does a very good job of it, and those with background can skim; this would be a great book for a child or teen interested in science.

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