I hated animals. I had always hated animals. I would never not hate animals, and I had told my biology teacher, Mr. Winalt, a thousand times I wanted to drop his class and yet here I was on this damn field trip to the zoo. Before we left, my teacher confronted me personally. “Josh, I know you don't share my affinity for nature, but if you allow me, I guarantee you my class will offer plenty to learn about biology. Who knows, you may even discover a thing or two about yourself.” I don't know if he meant to capture my interest or earn respect, or whatever the purpose of his little heart-to-heart was, but he sure didn't accomplish it. I'm not one to be swayed by some teacher's corny speech coated with theatrical empathy.

Now Mr. Winalt was leading us through each exhibit in some sick state of euphoria he was thrust into by the animals, insects, and other creatures here. “Fascinating, aren't they?” he said with child-like enthusiasm as he gazed dreamily at the herd of horses we had stopped to study. One student was switching songs on his iPod. Another was texting on her phone using only enough discretion to fool our entranced teacher. After what should have been a disheartening silence from the class, Mr. Winalt continued, “Okay, who can tell me what biological similarities exist between these horses and us?”

I turned to see the milky, dark eyes of a brown horse and a white horse with black patches by the feeder as they absent-mindedly chowed down lunch. A few beige horses with their knees folded into their stomachs were either resting or straight-up asleep. And some muscular dark ones were galloping aimlessly making their sleek tails and smooth manes fly in the wind.

I compared their features to my own. I have brown hair that isn't straight but isn't quite curly. It goes past my ears but isn't long enough to make me look like a girl. My eyes are a soft brown, and I have a wide jaw with a white scar on my chin. I'm 5Ƌ" and Caucasian with tan skin. Now, granted I am short, but nobody was half the size of the horses. They have four legs; I have two with arms. And finally, I've got leg and arm hair but nothing compared to the full coats of the horses.

I leaned over to my friend Jake and whispered, “If, on a scale of one to ten, one is thrilled and ten is bored to the point of death, I'd say I'm about a 9.5.” The corners of his mouth curved into a smile that said he was too tired to laugh.

Finally, after a good 30 awkward seconds of Mr. Winalt roving his gaze over the class with no answer, I decided I'd have to at least say something.

“I don't really see much in common between the horses and me; I mean … they have hooves!”

After some murmurs of agreement, Mr. Winalt said knowingly, “True, true. But take a look at your fingernails. The same dense material is actually found in that horse's hoof!” This drew some intrigued whispers from classmates as they looked back and forth between their nails and the horses' feet. “As a matter of fact,” said Mr. Winalt, “you will find there are deep-rooted genetic similarities between several animals and us. These commonalities are some of the strongest evidence that pointed scientists to the theory of evolution. Did you know that 99 percent of chimpanzees' genetic makeup is exactly the same as humans'?”

Despite more oohs and aahs, for me this field trip was every bit as dreadful as I had expected, and required every drop of will power from the tips of my toes and fingers to the strands of hair on my head not to ditch everyone when we moved on to the chimpanzees.

I can't explain why, but when the rest of the class found this field trip as dull and meaningless as I did, it gave me some sort of satisfaction. But now that Mr. Winalt had earned their undivided attention, the part of my brain that had previously been spamming “I-don't-want-to-freaking-be-here-right-now” had me overloaded and into the realm of “your-mom-just-walked-in-on-you-and-a-girl-kissing” restless jittering. Even Jake had given up trying to sleep and was paying attention. As my class was soaking in Mr. Winalt's teachings like sponges of biological knowledge, I drifted off to the other end of the chimpanzees exhibit in order to get Mr. Winalt out of my sight – and earshot.

The chimpanzees were at least slightly more interesting than horses. Instead of just eating and sleeping, they were more active. One was picking bugs from another's head and eating them, which was gross but funny. And another sat in a corner away from the others scratching its butt, which was also gross but really funny.

I thought about Mr. Winalt's question back at the horse display – about having stuff in common. I looked at the furry creatures through the Plexiglas wall and decided I could accept the fact that we shared some genes, but 99 percent seemed a little far-fetched. Still, the chimps had hands and I had hands, even though theirs were black. They had two eyes on the front of their face and two ears, and they seemed to interact with each other in a human way. What I mean is, they recognized each other as individuals, whereas the horses just came off as a herd. I was still ready to get the hell out of the zoo at the first opportunity, but pretending to be vaguely interested in biology was at least curbing my boredom.

As I compared myself with the butt-scratching bug-eaters, I noticed certain differences they had that actually seemed … better. One chimp extended its leg, and then using its foot, picked up a banana and reeled it back into his hand. Instead of just pinching the fruit between its toes, which any human can do, the thing curled its toes around the banana and trapped it against the base of its foot. It was as though the chimp had two extra hands. Considering the time I had wasted trying and failing to pick things up with my toes to avoid wasting energy bending over, I was sold on the idea that the chimpanzee had outdone us on this particular evolution. And, the chimp was now happily peeling his banana.

As the chimpanzee munched, I was looking down at my shoe and testing to see what maneuverability I did have with my foot. I curled my toes one way as far as I could and then flexed them the other way, but never reached quite the same flexibility as my genetic cousin. Giving up, I looked back at the chimp. He'd beaten me to it.

As soon as I picked my head up I realized I had become the exhibit. The chimp was staring straight at me – no, straight at my right foot. He then started curling his toes in the same way I had just failed to. But he wasn't reaching for anything, just repeating the motion and looking straight at my foot. It was almost like … like he was showing me. He then made some chimp noises at me, looked directly into my eyes, and pointed straight at his foot not once but twice. He was showing me.

First I was disturbed. A chimpanzee at a zoo was interacting with me – no, reacting to me. I wasn't sure chimpanzees were supposed to be capable of this level of communication. Even more unsettling was that under my shoe nobody could tell I had just been trying to pull off the chimpanzee flexible foot stunt. The chimp certainly didn't see me trying to mimic him; he seemed to literally have read my mind. After processing this I was fairly disturbed. There's no better way to put it than I was scared.

I wondered if I was dreaming when a sensation like I'd never felt or heard described ran from nerves in my brain down my spine and through the back of my right leg, finishing at the arch of my right foot. I wouldn't call it pain, but it was close enough to confirm that I was not in a dream. After having had the most intense feeling of my life, I expected to feel more below my ankle. Instead I just became more aware of all the bones in my foot.

A lot happened in the next few seconds. First I felt the marrow in my bone become warm. In the latter half of that second, the same warmth spread to the rest of my bones and my actual marrow's temperature was flaming. By about the end of the next second my entire foot was searing with heat and I could feel an enormous pressure as if every joint and bone in my foot was being pulled apart, stretched, and flattened at once. ­Between the heat and pressure, I was sure my bones from my ankle down were undergoing a change and melting to liquid.

Somewhere in the midst of one or two seconds passing, I had opened my mouth to tell the whole world my agony but found I had no breath or energy for any conscious bodily function. I was just a fraction of mental sanity away from full-blown comatose, unaware of anything but the hell that had been unleashed in my foot. This I would call pain.

The entire event took barely five seconds but felt like an eternity. I was on the ground in a pool of sweat in front of the chimpanzees. My foot continued to pulse with pain and felt constricted. I limped with difficulty, focusing on each breath and willing myself not to pass out. I reached the closest restroom and locked myself inside a stall.

When I tore off my shoes and socks I only found a moment's relief. My foot no longer felt excruciating pain. As a matter of fact my foot didn't feel anything. My foot was gone. And in place of it, connected to my ankle in bone and flesh, was a hairy black foot with an opposable big toe.