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Serengeti Rules

🚀 The Book in 3 Sentences

One of my favorite books I read in 2021; it is a nice book with good and interesting points and is kind of tied to systems thinking. It is about trophic cascades as well as other things.

🎨 Impressions

It is quite tied to Systems. It is quite intersting read when you learn to think in systems.

✍️ My Top Quotes

  • Serengeti: Endless plains
  • Smallpox is estimated to have killed as many as 300 million people in the first part of the 20th century.
  • The average yield of corn has increased from 32 to 145 bushels per acre.
  • The concept of suicidal lemmings was invented by a person who had never seen a lemming in his life. He learned about lemmings by translating a book about lemmings in Norweigan.
  • "The cell adapts its work to its wants. It produces only what it needs when it needs it." - Francis Jacob
  • Monod´s double growth curve: Bacteria must adapt to different foods by making enzymes. When having two different sugars in the petri dish, there was a break in the growth curve of bacteria due to the bacteria switching to a new food.
  • There are 200 different types and more than 37 trillion cells in the human body.
  • Predators affect/stabilize communities by negatively regulating the population densities of the competitively dominant species.
  • Kick it and see biology: remove predators and watch of prey population behave. An example of this was removing wolves from Yellowstone.
  • When otters were decimated by fur hunters on the coast of California, sea-urchin started to multiply and live behind barren lands where there once was kelp forrests. When otters were re-introduced algae forest started to grow again.
  • Trophic cascades: strong top-down effect when removing a species from a food chain.
  • Pathogens act as keystone species, disproportionately affecting populations.
  • In Serengeti, animal the body mass correlates negatively with predation, sharp drop in predation levels at around 150 kg for the prey.
  • Predators cannot follow herds, as they are confined to territories to raise and protect their young, therefore migratory prey usually have a larger size than non-migratory.
  • Serengeti rules: Keystone species: Not all species are equal. Some species exert effects on the stability of the community that are not proportional to their biomass or numbers. Some species mediate strong indirect effects through trophic cascades. Competition: Some species compete for common resources. Species that compete for space, food or habitat can regulate the abundance of other species. Body size affects mode of regulation. Smaller animals are regulated by predators and larger animals by food supply. Density: regulation of some species depends upon their density Migration increases animal numbers by increasing access to food (reducing bottom-up regulation) and decreasing susceptibility to predation (reducing top-down regulation).
  • Keystone species: Not all species are equal. Some species exert effects on the stability of the community that are not proportional to their biomass or numbers.
  • Some species mediate strong indirect effects through trophic cascades.
  • Competition: Some species compete for common resources. Species that compete for space, food or habitat can regulate the abundance of other species.
  • Body size affects mode of regulation. Smaller animals are regulated by predators and larger animals by food supply.
  • Density: regulation of some species depends upon their density
  • Migration increases animal numbers by increasing access to food (reducing bottom-up regulation) and decreasing susceptibility to predation (reducing top-down regulation).
  • "It is failures in the regulation of numbers of animals which form by far the biggest part of present-day economic problems in the field. " - Charles Elton
  • In Bangladesh, Vietnam and Cambodia rice provides over 60% of daily calorie intake.
  • *In 1976 Indonesia, pestilence swept the rice fields. An insect called brown planthopper devastated the rice fields. 350,000 tons of rice were lost, enough to feed 3 million people over an entire year. When treated with pesticides, the insect population increased 800-fold. This was due to a multitude of factors: *
    • The insect had evolved resistance to commonly applied pesticides.
    • The pesticides actually increased the rate of egg-laying by about 2.5 fold
    • The pesticides killed wolf spiders and other natural predators of the brown planthoppers. Kill the predators and the prey runs amok.
  • In Ghana Olive Baboons are considered a major pest due to them stealing food from the fields. Consider them a “baboonic” plague :) A lot of the reason for this was the poaching of the predators that feed on the baboons.
  • Limnonology: The study of lakes.
  • Ecosystem carrying capacity: How much animal biomass can be sustained by the food and water present.
  • "Wisdom is the daughter of experience." - Leonardo da Vinci
  • "Solutions rests on good science, but implementation rests on good management." - Bill Foege (epidemiologist credited on the eradication of the smallpox campaign) in his book House on Fire.
  • In a meeting in Kenya in 1978, the director-general of the world health organization (WHO) asked Henderson (Donald, in charge of smallpox vaccination) what the next disease to be eradicated was. Henderson grabbed the mic and said the next deceased to be eradicated was bad management.
  • WHO's director-general opposed the smallpox eradication program and even UNICEF refused to fund it.
  • Play the last person to have been affected with smallpox virus in Somalia was healthcare worker Ali Maow Maalin, he had not taken the smallpox vaccine because he was scared of the needle. "It looked like the shot hurt!" Maalin now works with the polio vaccination program in Somalia; "To ensure Somalia will not be the nation with the last polio case."