Calvin, a distinguished Univ. of Washington neurophysicist, starts off this collection of essays with a wild surmise. We are right-handed (most of us) because women discovered early on that babies calm down when pressed where they can hear the heartbeat; that means cradling the baby with your left hand. Some wise lady tool-users also discovered that they could hold a child and lob a rock at a passing rabbit, thereby increasing the larder at little energy expenditure. Since one side of the brain is usually better at programming rapid sequencing (like throwing a ball), mothers with left-brain sequencers might then be more successful at hunting--and mothering--and thus increase their genes in the pool. Hence, the Throwing Madonna. Though Calvin milks this theme in the first few essays (in terms of bigger brains, handwriting, etc.), he admits it's conjectural, and then moves on. There is some fresh travel writing about what it's like to be a neurobiologist spending a year in Jerusalem--shopping in the souk, searching for leeches, rubbing shoulders with Arabs, Jews, and polyglot others. (Calvin found the atmosphere strangely peaceful--despite colleagues, on military duty, coming to seminars armed.) There are also first-rate chapters on what's happening in neuroscience, along with a fine essay on pain, a wonderful put-down of the right-brain/left-brain popularizers, and assorted pieces on linguistics, evolution, and cats. Not strictly a collection of essays in the philosopher/scientist tradition, then, but rather a mÃ‰lange of humor, conjecture, travel, and history--the better the less Calvin conjectures.