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he complete title of this non-fiction book is A Series of Fortunate Events - Chance and the Making of the Planet, Life, and You. It is a quick read - just 178 pages
in the hard cover edition that I borrowed from the library. Carroll shows the role that chance has played in some major events in our Earth's history. He is able to communicate ideas clearly, along with
a few doses of humor. Interesting facts are mixed in - did you ever wonder how fish can survive in the ice cold waters at the poles? It turns out that some fish have added an anti-freeze protein to their
DNA. This protein binds to particles of ice that form inside the fish, which prevents the tiny ice crystals from growing larger.
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Carroll's first topic of chance discusses the asteroid that struck Earth 66 million years ago and wiped out the dinosaurs. Asteroids this size striking the Earth are quite rare (judging
from the size of impact craters found on the surface of the Earth and Moon) - and humans are lucky that this one did hit, because the death of all the dinosaurs allowed mammals to flourish. Mammals had coexisted with dinosaurs for
a hundred million years prior to the Chicxulub impact, but because dinosaurs dominated, mammals remained just small burrowing animals for all of that time. Yet just a few hundred thousand years after the dinosaurs perished, fossils indicate that mammals
had grown larger than ever before to fill the ecological niche that the dinosaurs had previously monopolized. If that asteroid did not hit Earth, it is likely that dinosaurs would still rule the planet and we would not be here.
Carroll spends a lot of pages discussing Darwin and his discovery that species are not created by a divine being, but instead evolve by random chance from existing species. Darwin spent years studying the techniques of
pigeon breeders and their flocks (Darwin also took to raising his own pigeons) and he saw how characteristics good and bad could get passed onto other generations. Darwin reasoned that random mutations allowed animals
to adapt to their changing environments, animals fortunate enough to get a good mutation left more offspring, and so successful mutations were passed down to subsequent descendants.
There is a lot of material about DNA and how the A/C/T/G bases bond to form DNA, and how mutations can occur. There are some helpful diagrams that explain how the base-pairs bonds work, and how
they occasionally mismatch. There is an interesting story of a gay man named Stephen Crohn who watched many of his friends perish from HIV. Since he had some familiarity with the medical field (his great uncle identified the disease
we now call Crohn's disease), it occured to Crohn that he too should have contracted AIDs and died. But he was perfectly healthy - and so he told researchers that he ought to be tested for HIV for immunity. It wasn't until 1994 that
anyone got around to running the tests, but when they did, they discovered that Crohn's blood could not be infected with HIV. He was naturally immune. It turned out he had a beneficial mutation, he lacked a receptor protein
that the HIV virus needed to infect his T cells. Scientists now know how to make new HIV preventative medicines that block the T cell receptors.
The final section of the book talks about individuals and cancer. The longer you live, the more likely you are to get cancer. That's because every time a cell divides there is a chance that something
goes wrong in the creation of a new cell. Sometimes these mistakes result in cells that won't stop dividing, which then lead to tumors. Smoking and UV rays from the sun are problematic because they greatly increase the rate at which
cell division could go awry. This section also explains how our immune system is able to make antibodies that ward of infections from billions of potential threats.
There is an afterward in which Carroll imagines humorists discussing chance and the meaning of life. There are some good lines in there: "In a culture that needs caffeine-free
cherry chocolate Diet Coke, you'd best deliver information with entertainment." "Truth is the point of comedy. It's usually saying the right thing at the wrong time." It's a good way to finish the book.
I plan to look for more of Carroll's books. He has titles called Remarkable Creatures, Endless Forms Most Beautiful, and The Serengeti Rules that sound intriguing.
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