Humans are a cocksure lot. Every four years the Olympic Games bring forth the best athletic specimens Homo sapiens can muster: men and women who run and jump, stroke and tumble, put, pedal, and throw until winners are declared and the country that takes home the most medals gets four years of bragging rights. The winning athletes glory in selling sneakers.
But isn’t this all rather zoologically narrow-minded? What about nonhuman animals? Aren’t they athletic, too? After all, the foundation of the Olympics is locomotion, and the need to move has surely been one of the major forces in animal evolution, determining such basic issues as who shall eat and who shall be eaten. So one has to wonder: What if this year’s games in Atlanta were truly open to all comers, whether they came on two legs or four, or even on fins?
With disbelief firmly suspended, we therefore announce the inaugural All-Animal Olympics. First, a few ground rules. There will be no eating of the competition. No team sports (hordes of nonhumans make humans either too nervous or too hungry). And finally, since human brains make us so superior in the making and handling of tools, any gadget-based competition--javelin throw, shot put, shooting events (especially those)-- is banned. The events will thus be limited to running, swimming, gymnastics, and boxing.
Now let the games begin.
As the athletes enter the stadium, the crowd--humans on one side, various NHAs (nonhuman animals) on the other--lets out a literal roar. Initially the nhas have a lot to roar about, as they sweep the first five running events, ranging from 100 meters up to 1,500 meters. In all five, their entrant is the same awesome ringer, the cheetah. The fastest running mammal, the cheetah can hit a top speed of 60 miles an hour, more than twice the wimpy 27 mph human record.
The speed of a cheetah comes not from any single part of its body; rather the animal is a veritable symphony of specialized anatomy. Its oversize legs provide the thrust, but to make the most of this available leg power, the cheetah uses a highly flexible back, as well as shoulders that are attached to the torso only by a muscular sling. By bending its back and sliding its shoulders, the cheetah can impart an unusually wide range of motion to its legs. During a run, it can plant its hind legs in front of its forelegs, dramatically increasing its stride.
As we should have known from previous studies of the cheetah’s speed and oxygen consumption, it needs only 16 seconds to complete the 400 meters. The world record among humans in this event, 43.29 seconds, set by Butch Reynolds of the United States in 1988, is almost three times longer. Things get more embarrassing as the events get longer. The cheetah blazes its way through the 800 meters in about 32 seconds, much to the chagrin of Sebastian Coe of Great Britain, who set his 1:41.73 world mark in 1981. Even worse is the spectacle of the 1,500-meter race. The cheetah needs barely more than a minute to finish the run. Granted, our fielded entry is relatively weak. But even if we’d been running Algeria’s Noureddine Morceli, who set his 3:27.37 world record last year, we humans would have had to suffer the humiliation of watching our entrant get lapped two or perhaps even three times.
In fact, though, we’ve now got the cheetah right where we want him. Humans are hoping that the cheetah will become a little overconfident and decide to extend itself by running the 5,000 meters. Things could get very interesting, says Rodger Kram, a physiologist and biomechanist at the University of California at Berkeley and one of the commentators at the first All-Animal Olympics. August in Atlanta is hot, he points out, and cheetahs don’t like heat. They have a high normal resting body temperature- -about 102 degrees Fahrenheit--and muscular activity generates extra heat. At very low speeds most of the heat escapes the cheetah’s body, but once the animal gets up to just 10 miles an hour, 90 percent of that heat will stay in its body as long as it keeps running. It can’t sweat or pant fast enough to maintain a constant body temperature, so temperature rises, explains Kram. A cheetah can’t store up that kind of heat forever, and if its body temperature rises above 105 degrees, it breaks off its run. Thus after a mad dash to bring down prey in the wild, the cheetah will rest, panting, before eating.
Ethiopia’s Haile Gebrsalassie holds the 5,000-meter record at 12:44.39, which computes to roughly 15 miles an hour. At that speed a cheetah would overheat after about four minutes and have to stop and rest. A stupid cheetah might sprint the first 1,500 meters, Kram says, but then it would have to wait a long time to cool down before it could run again. Its midrace siesta might even be long enough for Morceli to catch up and win. The human wins big time, bets Kram.
Meanwhile there are other animals ready to go against us in the long-distance events. The dog and horse, both excellent runners, come out to the starting line for the marathon against Kenya’s Cosmas Ndeti, who set a record in the Boston Marathon with a time of 2:07.15. But before the race can begin, the human track coach comes storming onto the field with a physiologist, crying foul play.
For long-distance movement, the importance of powerful muscles fades and the supply of oxygen to the body becomes key. Animals that are adapted to long-distance running generally increase the oxygen flow with relatively large lungs and heart. But there is another way to boost oxygen delivery: add extra red blood cells, which ferry the gas to cells around the body. Human athletes have been trying to do this in the past decade by blood doping. They draw off some of their own blood several weeks before a competition; by the time of the event, their bodies will have regenerated enough blood to bring them back up to a normal supply. A few days before the event, however, they reinject their banked blood into their veins. The idea is to increase the amount of oxygen-carrying cells, which hypothetically would get more oxygen to the muscles, says Richard Karas, a cardiologist at the New England Medical Center in Boston.
Blood doping in this way is now banned in the Olympics. An athlete can legally get the same effect, though, by training at high elevations, where oxygen concentrations in the air are lower. The diminished oxygen stimulates the body to compensate by producing more red blood cells. As Karas points out, though, the problem with either kind of doping is that no one has proved that it works for humans. It certainly wouldn’t help the weekend warrior, says Karas, and at best it might shave a fraction of a second off a top athlete’s time.
While it may not provide an edge for us, it does work very nicely in dogs and horses, where it occurs naturally. Dogs sequester additional blood cells in the spleen, says Karas. When they exercise, they contract the spleen and squirt the hemoglobin into the bloodstream. Within about a minute, they’ve increased the oxygen-carrying capacity of their blood. The percentage of blood that is composed of red blood cells can jump as much as 25 percent.
While blood doping has its advantages, it also puts a burden on dogs and horses. Their blood becomes more viscous, so they need particularly big hearts to pump it. That may explain why we humans can’t take advantage of blood doping. Our hearts are not made to pump this extrathick blood, says Karas, so even if the blood content goes up, the flow must go down because the heart can’t keep up with it.
And so an embarrassing interlude stops the All-Animal Olympics for a moment, as the humans challenge the legality of the blood-doped dog and horse. The challenge seems pointless--clearly the nhas haven’t broken any rules. But rather than get embroiled in an interspecies scandal, they don’t even bother arguing the point. They simply bring in an unquestionably legal substitute--the kangaroo.
As it waddles up to the starting line, Ndeti can be forgiven for snickering at the notion that this pear-shaped, rabbit-headed marsupial can pose much of a challenge. But once the starter pistol is fired and the kangaroo starts hopping down the track, Ndeti quickly has second thoughts.
A hopping kangaroo--like many other running mammals, including humans--acts like a pogo stick. When you land on the ground during a run, you sink down and store some of the energy of your movement in the tendons of your legs. When the time comes to push back off the ground again, the energy is released, much as it is from the spring of a pogo stick. Without these elastic tendons, you’d have to make up for the stored spring with an extra boost of energy.
The kangaroo, simply put, is a fabulous pogo stick. It’s got this big long leg and long Achilles tendon, and a great big long foot, explains Terry Dawson, a zoologist at the University of New South Wales in Australia. It lands and pushes off again on its tiptoes. All that allows the legs to extend in a long arc as it bounces, and the legs are fully extended in front of its body when it lands. At the end of each long arc, the kangaroo stores some of its kinetic energy in its tendons; while running humans land on only one foot at a time, a kangaroo hops on both, doubling the energy storage in each stride.
When a kangaroo is going flat out, its stride length is getting up to 15, even 20 feet, says Dawson. You may not appreciate this great leap if you watch a kangaroo in full bounce, because it doesn’t rise very high with each jump; raising its center of gravity so much would be a waste of effort.
The race between man and marsupial isn’t quite the blowout that the cheetah sprints were, but it’s humbling just the same. On average, humans win marathons at a speed of around 13 mph. A kangaroo’s most efficient traveling speed, says Dawson, is around 16 miles an hour. But he suspects that kangaroos have the ability to go much faster. In his car, Dawson once clocked a bounding kangaroo for four miles at an average speed of 28 mph. Then the animal appeared to lose interest, effortlessly sped up, crossed in front of Dawson’s vehicle, and disappeared into the outback. So I’d guess that over and above their cruising speed, they have quite a lot of reserve, he says. I don’t think the kangaroo would be unduly pressed to run a marathon at about 16 to 19 mph. It would seem the human will always be eating ’roo dust.
Kangaroos have on occasion also been put in boxing rings, and they can deliver surprisingly strong swipes against humans with their forearms. But the nonhuman animals have decided to pick another species to go up against champion American flyweight Eric Morel. For boxing, special rules are in effect: the All-Animal Olympics rules allow the nhas to scale up any animal of their choice to human size. And their choice is a pugilistic crustacean known as a stomatopod.
The stomatopod is common in the shallow waters of tropical and subtropical oceans. The 500 species that make up this order range in size from a little over a quarter-inch to a foot and a half, and most spear their food with sharp spines on the ends of their forelimbs. But Morel’s opponent is a bruiser from the stomatopod family Gonodactylidae. Instead of spines it has two appendages, each of which has a hard, calcified bump at its end that it uses to strike out at its prey.
A three-inch-long stomatopod can take a large snail and pulverize it--we’d need to hit it a couple of times with a ball peen hammer to smash it, says Roy Caldwell, a marine biologist at the University of California at Berkeley. Studying these beasts is no easy task, as Caldwell can attest: they’ve smashed the glass walls of his regular aquariums (he now keeps them in Plexiglas tanks). Trying to measure the force of their strike offers its own troubles to Caldwell and his Berkeley co-worker, biomechanist Robert Full. It’s been a nightmare--we keep breaking the equipment, says Caldwell. The best we’ve done is to estimate the power of the strike by measuring the mass of the animal’s appendage and its speed when it strikes an opponent. We estimate that a small, two-inch gonodactylid has the striking power of a pellet pistol.
Not only does the stomatopod have great offense, but it has defensive moves in the ring as well. The crustaceans fight from a coiled posture, lying on their back, and can thereby use their tail as a shield. The muscles in their abdomen work like a spring or shock absorber, says Caldwell, so an opponent’s strike that lands on the tail doesn’t do a lot of damage, because the shock is absorbed. Combining its movements of tail and striking appendages, a stomatopod can feint, bob, and weave. Its trick is to parry another stomatopod’s blows with its tail and then make a split- second lunge out of its coil to land a blow itself, Caldwell says. There’s a lot of probing and feinting going on--they seem to elicit strikes on their tail deliberately just to measure strength.
In the ring, Morel’s best strategy would be to dodge the stomatopod’s blows until it wears out. After a few strikes, the muscles inside its appendages become exhausted, and it must rest to build back its strength. As it turns out, Morel dodges the stomatopod’s blows for a while, and he gets in a left hook while the stomatopod is trying to regain its strength, but then the crustacean responds with a single pistol-like blow. Game over.
Things aren’t going much better on the other side of the arena, where a small monkey is twirling circles around the human gymnast on the uneven parallel bars. For this event, the nha Organizing Committee selected the gibbon. It’s a perfect choice: these long-armed tree-dwelling primates from southern Asia are used to swinging at high speed from uneven branch to uneven branch. Gibbons use their forelimbs for locomotion; like humans, they’re very forelimb dominated, says Sharon Swartz, a biologist at Brown University. And, like humans, they have unusually good manipulative abilities in their forelimbs. A lot of gymnastics has to do with grasping and reaching.
Other primates swing through the canopy, but they can’t compete gymnastically with the gibbon. Size is one important factor: a 150-pound orangutan has to move slowly and cautiously because it has to burn a lot of energy to move its great mass; it’s more likely to break a branch; and a fall is more likely to kill it. A gibbon’s light weight, on the other hand, allows it to move quickly and acrobatically from branch to branch, harnessing the gravity of its pendulum-style movements for extra efficiency.
What makes gibbons particularly good gymnasts, though, is their anatomy. They have an additional little ball-and-socket joint within the wrist joint that gives them an extra 90 degrees of rotational ability within the wrist, explains Swartz. Think about grabbing a bar and rotating; mostly you’ll rotate at your shoulder and elbow joint. But gibbons have that additional joint to add to the rotation. They have another ball-and-socket joint at the base of their thumb, which allows the thumb to grab branches of widely different sizes and shapes.
Swartz bets the gibbons will be spectacular on the uneven bars. Their light mass and very long limbs are going to give them a high and impressive velocity when they swing, she says. Also, when they move around a forest canopy, they take advantage of their ability to change direction quickly, so the kinds of swinging and aerial somersaults that might be needed in grabbing a branch are the kind of maneuvers they could employ in a hypothetical competition.
By the time the all-animal Olympics move out to the pool for the swimming events, the humans are a despondent lot, desperate for a win. But it’s not to be. Here, in fact, humans do worst of all. It shouldn’t be surprising, given that our opposition, the barracuda, is a beautiful product of aquatic evolution, while we have been out of the water for 360 million years. I once calculated that at his best, Matt Biondi could swim between 4 and 5 miles per hour, says the appropriately named zoologist Frank Fish, of West Chester University in Pennsylvania. That’s just incredibly slow compared with the swimming efforts of fish and marine mammals. Some fish, like the barracuda, sprint at speeds of 45 mph at least.
Key to the difference in speed between man and fish is the drag that each creature creates in the water. Roughly speaking, the more area of an animal’s body that is perpendicular to the direction in which it is swimming, the greater the drag. Thus barracuda reduce their drag dramatically by means of their elongated teardrop shape, while humans create drag with their broad shoulders, heads, and arms.
Where an animal swims can also make a great difference to its drag. Barracuda, thanks to their gills, can swim far under the waves of the ocean’s surface. Humans, dependent on air, splash their way across the top of the water, fighting waves, including those that they themselves create. Humans can improve their race times to some extent by swimming underwater as long as possible, and some Olympians have actually done this (it’s now illegal). Still, there comes a time when humans have to breathe air, and when they come to the surface, they’ll once again produce drag-increasing waves. Of course, other mammals, like dolphins and seals, must also come to the surface to breathe, says Fish, but they can reduce their overall energy cost by leaping, or ‘porpoising,’ from the water. Finally, barracuda also cut down on their drag with a slime they secrete from mucous cells. No matter how much an Olympic swimmer drools, he or she cannot reduce the drag by this mechanism, notes Fish.
Not only do humans create far more drag than barracuda, but they can generate woefully little thrust underwater. A fish swims by using its entire axis and tail to create waves that roll down its body and propel it forward--thus using most of the muscles in its body to move. A human, on the other hand, mainly uses the muscles in the limbs. And while a barracuda can generate huge amounts of thrust with its wide tail, we humans generate most of our thrust with our relatively puny hands.
If you look at the ability to take metabolic cost and convert it to useful work--in this case, to produce thrust, says Fish, then humans are only 5 percent efficient in water. Fish, sea lions, and dolphins, though, are between 15 and 30 percent efficient in swimming.
In the end, humans garner no gold in these imaginary All-Animal Olympics. Is this reason to despair? Not to biologist Steven Vogel of Duke University. On the contrary, he thinks there’s something fitting in this. We can’t beat the pros, he says, but on the other hand, other animals don’t have a single species that could enter every Olympic event. We can swim, climb trees, and run, but we can’t do them as well as the specialists. What we are is multifaceted. We’ve been designed for terrific behavioral versatility.