The Evolution of the Fastball

It is a scientific fact: Man evolved to throw and to hit baseballs. Even before we were advanced toolmakers, we were proficient throwers and clubbers. These skills and the anatomical specialization to perform them well are uniquely human. Our nearest cousins, chimpanzees, will occasionally toss sticks and rocks around but they cannot direct them accurately. Many paleontologists believe that the development of the ability to throw and to swing sticks with accuracy and authority marked a major turning point in hominid evolution. These capabilities enabled early hominids to escape the tedium of playing soccer and had enormous social advantages as noted by Professor Richard Young:*

“The best throwers and clubbers in a community would rise in the male dominance hierarchy and thereby obtain more breeding opportunities.”

Any evolutionary advantage that confers a rise in the male dominance hierarchy and greater access to breeding females is sure to spread rapidly through the species and to be continually refined by competitive pressures. The relative advantages of exceptional throwing and batting skills persist to this day, as a quick glance at the seating section for ball players’ wives and girlfriends confirms. (More evidence could be cited easily but this is a family-friendly blog.)

The critical evolutionary developments for throwing and hitting came in the shoulder and hands. The shoulders of other apes are designed so that the socket accommodates vertical extension of the arm – handy for hanging from trees but not so good for pin-point control from the mound. The human shoulder has the greatest degree of rotational movement of all our joints and it is also the most vulnerable to injury. Baseball made famous the rotator cuff, the bundle of muscles and tendons that hold the upper arm and shoulder together. The fellow below is doomed to hang around in the bush leagues.

Our hands and fully opposable thumbs are far better suited for throwing and especially for gripping bats and racquets than those of chimpanzees whose hands likely resemble those of our common ancestor. Even the fatty tissues or pads on our hands are positioned and sized to absorb the impact shocks of clubs and bats colliding with skulls and baseballs.

Our throwing ability has come pretty far in the past 500,000 years or so. The Baseball Almanac lists 27 pitchers whom have reached or exceeded 100 miles per hour in a game since Nolan Ryan cranked it up to 100.9 in 1974. The fastest speeds on that list belong to Mark Wohlers a former Atlanta Braves’ closer, who recorded 103 mph in a 1995 spring training game and Joel Zumaya, a Detroit Tigers reliever who reached 103 mph in 2006. The current record is held by The Cuban Missile, the Reds’ Aroldis Chapman, who was recorded firing a baseball at 105 mph in 2010.

Evidence on a pitcher’s velocity was very spotty in my dad’s day and not much better in mine. For the most part, the relative speeds of pitchers were judged subjectively by other players. Technologies such as photovoltaics and slow motion cameras that used frame counts to estimate speeds had progressed somewhat when I started paying attention but they were primitive compared to the radar guns that became standard in the 1980s.

Before the radar gun became a fixture at ball games, pitchers had to travel to laboratories, often weapons facilities with the expertise to measure projectile speeds, and use various paraphernalia to measure the velocity of their throws. In 1917 a Bridgeport Connecticut weapons laboratory using a device called a gravity drop interval recorder** clocked Walter Johnson at 91.36 mph, Christy Mathewson at 86.59 mph and “Smoky Joe” Wood at 84.55 mph. I suspect that, like a stop-watch, these devices were triggered by human action and the tiny delay this entails accounts for the relatively low measured velocity.

The recently deceased Bob Feller, the great Cleveland Indians’ pitcher of the 1940s and 50s who was known as Rapid Robert was especially eager to measure his heater. A famous black-and-white film shows Feller throwing a baseball past a speeding police motorcycle at Aberdeen Proving Grounds. Although the test is inherently flawed, Feller claimed that he was measured at 104 mph. In 1939 Feller and teammate Johnny Humphreys threw baseballs into a 2-foot square hole cut in the side of a trailer in which photovoltaic tubes spaced 5 feet apart measured the balls’ velocity. Rapid Robert’s reading that day was a less-than-spectacular 81.14 mph, significantly slower than Humphrey’s 86.59 mph which equaled Mathewson’s earlier trial.

How fast can a ballplayer throw? We might already be at or near our natural physiological limit. At this point in our evolution, the human elbow is likely be the limiting factor in how hard a pitcher can throw. Glenn Fleisig, a scientist at the American Sports Medicine Institute, tested cadaver elbows (the first thing most kids ask when told this is “how do you get a bunch of cadaver elbows?”) and found that their ulnar collateral ligaments (UCLs) snapped at about 80 Newton meters (about 59 foot-pounds for those of us who have adopted non-metric standards – Myanmar, Liberia and the USA) which is approximately the same rotational torque as experienced by a professional pitcher’s elbow in throwing a fastball. UCL replacement is better known as “Tommy John surgery,” named after the first pitcher to undergo the procedure. Curiously, many pitchers return from UCL replacement surgery throwing faster than before. This raises the issue of whether discretionary surgical arm enhancement might be pursued in the future and how it ought to be treated relative to chemical enhancement.

There has been some recent discussion that human athletic performance is peaking. Records last longer and many believe that we’ll soon exhaust our native potential. I’m not so sure, the performance enhancing drug era proved that we could exceed normal constraints with a little help from chemistry. The next era of enhancement may be surgical improvements to what Nature has given us.


*Richard W Young, Professor emeritus, Department of Anatomy, University of California Medical School, Los Angeles, California, “Evolution of the human hand: the role of throwing and clubbing,” Journal of Anatomy, 2003 January; 202(1): 165–174. Professor Young’s article focuses on evolution of the hand for throwing.

**I have tried unsuccessfully to find out what a “gravity drop interval recorder” was.  Ballistics experts and physicists I have asked have not heard of the device.  I suspect it was a contraption that utilized the known and constant rate of acceleration due to gravity to time a ball over some course but have no idea how the beginning and termination of the ball’s flight was captured by the machine.  If a reader knows about this apparatus, I’d appreciate learning more about it.

Posted by Bob


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s