The average NFL player earns $1.1 million per year, and the average NBA player makes $4 million per year. Yet even these vast incomes sometimes aren’t enough to cover what players spend. In a recent issue of Sports Illustrated, Pablo S. torre described how and why athletes go broke (you can read his article at http://tinyurl.com/brokeathletes). He writes that after 2 years of retirement, “78% of former NFL players have gone bankrupt or are under financial stress.” Within 5 years of retirement, roughly 60% of former NBA players are in similar positions.

Beware of shopping momentum. Researchers at Stanford University warn that shopping can lead to more shopping: At first you deliberate over whether to buy something, weighing the pros and cons. But once you’ve made the decision to buy, you spend less time deciding on additional purchases. this phenomenon, dubbed shopping momentum, increases the likelihood you’ll buy more.

I’ve suggested some of my own. You can accept these or not, as you wish. The question you face is that of a jury member: is this idea sound “beyond all reasonab

I’ve suggested some of my own. You can accept these or not, as you wish. The question you face is that of a jury member: is this idea sound “beyond all reasonable doubt?” If you don’t accept an explanation for an event, you can leave it as an abominable mystery, with no explanation at all, or you can suggest a better explanation yourself.
There is one caution, however. No-one is allowed to dream up any old explana- tion for past events. A scientific suggestion (a hypothesis) has to fit the available evidence, and it has to fit with the laws of physics and chemistry, and with the prin- ciples of biology, ecology, and engineering that have been pieced together over the past 200 years of scientific investigation.
There’s yet another wrinkle. A jury decides on a case, once and for all, with the evidence available. But in science, the jury is always out, and new evidence comes in all the time. You may have to change a verdict—without regret, because you made the best (wrong) decision you could based on the old evidence. Some of the ideas in the earlier editions are wrong, and you won’t find them here; you’ll find better ones. Sometimes the new answer is more complex, sometimes it is simpler. Always, how- ever, the new idea fits the evidence better. That’s simply the way science works: not on belief, not on emotional clinging to a favorite idea (even if it is your own), but on evidence.
I never expect to be able to write the final solution to the major questions about the history of life, but I do expect to be able to provide better answers this year than I could last year. If my lectures are the same this year as they were last year, then something is wrong with our science, or something is wrong with me. Paleontology is exciting because it is advancing so quickly.