Slime: How Algae Created Us, Plague Us, and Just Might Save Us – Ruth Kassinger

Thoughts: I enjoyed reading Slime, and found sections I and II particularly interesting. Maybe I’ll eventually get around to cooking some of the recipes Kassinger provided in an appendix.

(The notes below are not a summary of the book, but rather raw notes - whatever I thought, at the time, might be worth remembering.)

Kassinger, Ruth. 2019. Slime: How Algae Created Us, Plague Us, and Just Might Save Us. Houghton Mifflin Harcourt.

Introduction

• xii-xiii: “algae” is a polyphyletic group: “Algae… is a catchall term, a name for a group of diverse organisms.”
  • types of alga:
    • cyanobacteria (aka blue-green algae): single-celled, “internally simple” bacteria
    • microalgae: single-celled, “internally complex”
      • 19: eukaryotic cells that acquired cyanobacteria
      • xii: collectively, cyanobacteria and microalgae are known as “phytoplankton”
    • macroalgae: multicellular, i.e. visible seaweeds
  • algae all photosynthesize (or did, at some point in their evolutionary past)
  • algae are not plants (i.e. not in the kingdom Plantae)

Section I: In the Beginning

1. Pond Life

2. Something New Under the Sun

• 12f: “The very first photosynthesizers did not produce oxygen. Instead, they captured near-infrared light with a purplish pigment, stole electrons from sulphur compounds in the water, and pooped microscopic grains of pure sulphur as waste. They never prospered the way their [cyanobacteria] cousins did, but their descendants carry on in anaerobic waters today.”
• 14-15: as algae proliferated and photosynthesized early in the evolution of life on earth, the atmosphere did not begin to switch from anaerobic to oxygenated until all the oxidizable metals dissolved in ocean water rusted and precipitated out of the water. Even after that had happened, all the iron on the earth’s surface needed to rust away before oxygen began to accumulate in the atmosphere.

3. Algae Get Complicated

4. Land Ho, Going Once

5. Land Ho, Going Twice

6. Looking for Lichens

Section II: Glorious Food

1. Brain Food

• 48: Lack of access to seafoods tends to lead to iodine deficiency. “It is difficult to appreciate how common iodine deficiency once was and how often it harmed full cognitive development.”
• 49: DHA: “Algae also provided another ingredient essential for evolving larger brains: the polyunsaturated fatty acid called docosahexaenoic acid…. [DHA is] one of two kinds of omega-3 oils.” DHA is crucial for the creation of neural synapses, and triggers genes that promote brain growth

2. Seaweed Salvation

• 57: seaweed is very nutritious: nori, for example, is rich in vitamin A, vitamins B, calcium, iron, protein, and several other nutrients

3. On a Grand Scale

• 65f: Kassinger recommends buying seaweed snacks only if they are organic: seaweed must be grown in clean waters, because it’s easily accumulates metals/minerals from the water in which it is grown. Buying seaweed snacks marked as organic is, evidently, a way to ensure they’ve been grown in waters that are not too polluted.

4. Welshmen’s Delight

5. A Way of Life

• 80: “When two or more umami-containing foods are mixed together, such as the wakame, kombu, miso paste, and bonito flakes in miso soup (or the tomatoes, parmesan and anchovies on pizza), the combined flavour intensity is greater than the sum of its parts.”

6. Flash!

Section III: Practical Matters

1. Feeding Plants and Animals

2. In the Thick of It

3. Land Ho, Going Thrice

• 127: “According to the Japanese tradition of Washoku…, an appetizing and healthy meal has five colour elements: white and black—often provided by rice and nori—plus green, pink, and yellow.”

4. Seaweed Stuff

• 146: John Wesley Hyatt invented the first plastic, celluloid, in response to an award offered by a billiard ball manufacturer, who wanted to find a replacement for ivory for use in billiard balls.

5. Algae Oil

6. The Algae’s Not for Burning

7. Ethanol

8. The Future of Algae Fuel

• 187: Klaus Lackner “has invented a passive air filter made from a commercially available white plastic resin that naturally absorbs carbon dioxide. When air passes over a dry filter, the resin absorbs the gas; when wetted, the recent releases CO2 as a stream that is 100 times more concentrated than it is in ambient air. The filters can be endlessly reused.” wow!

Section IV: Algae and the Changing Climate

1. Gadzoox

• 202: why corals eject their algae symbionts when they get too warm: “under the stress of high UV light and heat, [zooxanthellae, the algae that normally live within coral polyps] produce more superoxides, that is, oxygen molecules with a negative charge. Superoxides are highly reactive…. They damage chloroplasts and mitochondria, destroy lipids and ATP, and break down cell membranes…. When polyps sense the danger from their overactive [zooxanthellae], they expel them.”

2. Saving the Reefs?

3. A Plague Upon Us

4. Cleanup

5. Making Monsters

6. Geoengineering

• 250: experiments in iron seeding (to promote the growth of algae, which fall to the ocean floor when they die and thereby sequester carbon) have shown that “it takes a relatively small amount of iron to produce large amounts of organic algal carbon: one pound of iron can fix eighty thousand pounds of carbon dioxide.”
  • but values vary dramatically depending on local conditions, there are questions surrounding how much carbon actually falls to the ocean floor, etc.
• 250-251: dimethylsulphoniopropinate (DMSP), a compound released by algae, plays a major role in seeding clouds.
  • 251: “Some scientists posit that increasing [dimethyl sulfide, which is created when bacteria break down DMSP] in even a small portion of the Southern Ocean would have a large cooling effect—but not a greenhouse gas-reducing effect—on our planet.”

Epilogue