Thoughts on the End of Natural Selection 🌱

https://lifeclub.org/books/hacking-darwin-jamie-metzl-review-summary

https://jamesclear.com/book-summaries/sapiens

The Gene: my notes

Natural selection for humans has been on its way out for hundreds if not thousands of years

• Cognitive revolution
  • monkeys have been shown to lie, but only humans have been shown to be able to speak about imaginary concepts
  • Chimps can’t form groups of more than 50 or so. For humans, the group size is usually 150 or so. Beyond that, you can’t rely on gossip and personal communication. You need something more to get large numbers of people working together. Large numbers of people can collaborate by sharing common myths and beliefs.
  • Homo sapiens are the only animals that conduct trade.
  • As far as we know, the humans of 30,000 years ago had the same physical, emotional, and intellectual capabilities that we have today.
  • The human collective today knows far more overall than the whole population of 15,000 years ago. However, at the individual level we are much more specialized today. Ancient foragers were the most knowledgable and skillful people in history.
  • It is far easier to pass “unremarkable” genes along today than it was 10,000 years ago.
• Agricultural revolution
  • Fascinatingly, the first few thousand years of the Agricultural Revolution actually made life harder for humans by creating more work, less leisure, and a ballooning population that created more mouths to feed. Each individual generation didn’t see how their life was becoming worse because the small changes were so tiny.
    • variable crop yields dependent on weather that could mean like or death
• Scientific revolution
  • More than 90 percent of all money is just electronic data, not physical money.
  • Each year the United States population spends more money on diets than the amount needed to feed all the hungry in the rest of the world.
• The shared “myths” (think religion, capitalism, and politics) have enabled humans to take over the globe and have put humankind on the verge of overcoming the forces of natural selection.
• Homo sapiens may only survive for another few hundred years or so
  • we kill ourselves
  • we change our species rapidly through genetic engineering or some other technology (maybe AI)
• For close to 4 billion years, every organism developed according to evolution. But in recent decades, humans have begun to evolve according to intelligent design. In other words, there are people who would have been selected out of the gene pool millennia ago, but not today.

The Gene:

• Of the millions of biological molecules in the human body (including enzymes, receptors, hormones, etc.), only 250 or 0.025 percent are theraputically modulated by our current pharmacopeia.
• Mitochondrial DNA is only inherited from the mother and we can trace back the mitochondrial DNA for everyone back to the same single women hundreds of thousands of years ago.
• Humans have less genetic diversity than apes and most other species (because we are younger)
• The vast proportion of genetic diversity (85-90%) occurs within so-called races, not between them
• natural selection was subjective: Dyslexia may have been a useful genetic variant in the past for allowing hunters to focus on multiple targets at once, but now in society it is an illness

What is Natural?

• If it is possible biologically, then it is natural. From a scientific perspective, two men having sex is natural. Traveling at the speed of light is not natural.
• Some people born with Swyer syndrome have XY chromosomes, but they develop and identify as female. This is because they have mutations in their SRY gene which controls flipping on the genes in the Y chromosome. Inserting extra SRY genes into rats turned their female offspring with XX into males.
• Author consistently gives arguments and examples that genes (supported by twin studies) govern your propensity to respond or act a certain way (you can think of it as the gradient/first derivative), but not that actual outcome of how you act
• Environmental impacts on genes can be passed down. For example, famine during WW2 in Netherlands “Hongerwinter” caused many of these people to be malnourished and the children of those who survived (and their children) were often obese and suffered heart disease later in life because they inherited genes from their parents with these epigenetic markers that allowed the parents to survive the famine.
• The epigenome is what changes throughout a person’s life. The influence of “nurture” is only existing in how it is reflected back in the “nature”. The underlying genes are the same over time, but how they are packaged (histones) change