Wednesday, 28 February 2018

Review: What Makes Biology Unique: Reflections on the Autonomy of a Scientific Discipline by Ernst Mayr

Ernst Mayr was a huge figure in the modern evolutionary synthesis and was referenced a ton in books I read for Schols (both negatively and positively). I have mixed feelings on him myself but was interested in the idea of the autonomy of biology in the face of physicists and chemists claiming it's within their subjects, so I read this book. 

Mayr talks about different kinds of science, and how it's not just experimental science but also what he calls 'historical science', often employed by evolutionary biologists, where you come up with a hypothesis/historical story for how things happened and see how well that matches up with the available evidence. 

He distinguishes between functional biology, which talks about how things work and in his mind can be reduced to chemistry and physics, and historical biology, evolution and ecology, which is his field. He says functional biology mainly asks how, historical biology why, and they use different methods. He mostly only defends historical biology, but some of his arguments apply to both. 

Physicalist ideas he says don't apply to biology:

  • Typology -- in biology, there aren't a limited number of things, where all things of each type are the same (e.g electrons); instead, evolutionary biologists go for population thinking, which acknowledges that organisms even within one species or population vary, and means that, to borrow a lovely phrase I got from Ridley's Evolution textbook while studying for Schols, means that even though sparrows vary in size across North America, 'all sparrows are equally good sparrows'.
  • Determinism -- even if you know the position and momentum etc of everything, you can't predict biology with certainty into the future. Physicists realized that a while after Laplace said you could, but it's especially important in biology where chance drives the variation needed for evolution to occur. 
  • Reductionism -- the idea that if you know what each component of a complex system is and what its function is you can understand and explain the whole system. Whole chapter devoted to this so read on.
  • Universal natural laws -- don't really apply in evolutionary biology, so Popper's falsificationism doesn't work. He says biological theories are based more on concepts than laws, and then showing that he seems to think all of biology is just evolutionary biology, says: 'Examples of concepts that became important bases of theories in various branches of biology are territory, female choice, sexual selection, resource, and geographic isolation.' 
Autonomous features of biology:
  • Complexity of living systems
  • Evolution
  • Open systems in regards to entropy
  • Dual causation -- controlled not only by natural/physical laws but also by genetic programs. 
Chapter 3: Teleology

He also talked about a bunch of philosophical issues like teleology (goal-directedness of something), which he resolved by splitting the broad word teleology into five types e.g. teleonomy and saying four are proven by science while the fifth, cosmic teleology (everything leading to a cosmic purpose/for god), doesn't exist. In his chapter on Analysis vs Reductionism, he talked about how physicists like to break everything down to atoms and quarks but in biology the way things are arranged is as important as their parts and is an emergent property, and often in biology it's not actually any more helpful to go below a certain level e.g. you can understand cell signalling well just from molecules and the odd atom without understanding quarks, since the link from quarks to atoms and atoms to molecules is already built by physicists and chemists. I agree with that, although he did caricature physicists and reductionism a bit. 

In Darwin's Influence on Modern Thought, he talked about how people say Einstein's relativity revolutionised how people think about the universe but it didn't -- only strong physicists really benefitted from it or felt the revolution. In contrast, he says, Darwin's theories (he says there were five, including evolution, natural selection and common descent) really did change the way the public thinks about the world. 
In Do Thomas Kuhn's Scientific Revolutions Take Place?, he argues that Kuhn's idea of a  cycle of paradigm change ('revolution') followed by a period of 'normal science' doesn't apply to biology, which has mostly seen steady progress as we gain more knowledge and understanding. He makes the important point that most philosophers of science are really philosophers of physics, which rang true from my experience. I've only read about a couple of philosophers of science (mainly in the book The Meaning of Science by Tim Lewens, review here, which discussed Popper and Kuhn among others), but their work does seem to have been based on physics, at least in the examples they gave. 

He has a whole set of chapters on evolutionary theory, which were ok but not what I read the book for. I had to force myself to read his 'another look at the species problem' after studying that as the Schols special topic, and similarly with his other evolution chapters I already knew most of it from Schols study. The 'origin of humans' chapter wasn't great bu I generally just find that topic really boring, even in lectures. 

He randomly has a chapter 'are we alone in this vast universe?' about aliens, in which he basically says we shouldn't look for them and they wouldn't be sentient, and gives out for a while about SETI. As another reviewer said, it'd have been better if he'd written something about what discovery of alien life would mean for evolutionary theory and how interesting that would be. 

General Criticisms:

  • he doesn't really introduce concepts, though he does have definitions in the glossary
  • loves sound of his own voice -- that said, the book is short, which I appreciate
  • distinctions can seem pointless, as between some of the types of teleology
  • so many squabbles in evolutionary biology! 
Overall it was a fairly interesting read, but only a few of the chapters were on what the title promised, and he only seems to view evolutionary biology biology, with molecular bio just chemistry. 

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