Chemblog!

Today, you can witness the great spectacle of the second leg of the Triple Crown. Just two weeks ago, you saw Street Sense accelerate like a '75 Cadillac and go from 19th to 1st place and then pull away from his "peers" in the Kentucky Derby. Today, he faces some new wannabes/challengers in a smaller field of 9.
Now let's talk about Biology. When you watch horse racing, you are witnessing several hundred years of human-caused evolution. Horsemen have "selectively bred" horses that have the most desirable traits, speed and stamina, for the past three hundred years. In fact, the modern thoroughbred horse can trace its roots back to Britain where three top Arabian horses were imported and bred to some native Scottish mares. The result was a new breed of horse, the Thoroughbred (still the same "species" as the other horses, though, because they can interbreed and produce fertile offspring.) The main three horses who are the great-great-etc. grandsires of almost all modern thoroughbreds are Herod, Eclipse, and Matchem. The Horse of the Year awards, in fact, are called "Eclipse Awards".
Selective breeding has both positive and negative aspects. Though thoroughbreds (and standardbreds, harness racing horses) have gradually been able to achieve faster and faster times over various distances, the breed has become noticeably more fragile! Most horses in the US race while on a drug called Lasix, which is an anti-hemorrhaging agent. You know that, back in the day, Seabiscuit never even heard of Lasix. You may have also witnessed various horses who have broken down or broken their bones (a life-ending injury for such a massive animal). Recall the great Barbaro from last year's Preakness.
This is no accident; as you know, "in-breeding" can increase the frequency of horses with genotypes that are homozygous for deleterious traits (this goes for dogs and cats, too!). Responsible breeders are aware of the dangers of too much in-breeding and try to use a larger variety of sires and mares in creating the next generation of horses.

Okay, now let's get to cases: I think that Street Sense will again fly by his opponents todayin the Preakness. He just does not like to lose and he has a strange proclivity for running right next to the rail. I think that he will sit back on the rail and then motor by everyone else again.
There is always the possibility of an upset, duh. If any horse might be ready, I think that Circular Quay might follow Street Sense and try to take the race. CQ had been resting for eight weeks before the Derby so maybe he needed that wakeup call to get prepped for this race.
There are a bunch of other horses but I think that, as good as their trainers are, the talent just isn't there.
Look for the tradition of draping the winner, not in roses, but in "Black-Eyed Susans", flowers that have to be PAINTED because they are not in season in May!
Enjoy the races, NBC at 5PM from Pimlico Racetrack in Maryland!