I'm a scientist.

That phrase seems to have a different meaning to the general public than it has in the science community. Most people think of lab coats and bubbling beakers, or wild-haired and absent-minded-but-kindly professors. But to us, science is a process -- lots of study to master one's field, then hard work, careful documentation, peer review, and publishing. In some fields, especially when the work has direct effects on humans, we deal with very stringent regulations concerning the type of experiments we can perform.

I accept those constraints. They were put in place for a purpose, to guarantee valid results and protect the public from exposure to unknown dangers. But sometimes it seems that the process has the opposite effect. Our discovery has profound implications for society, and we'd never have known that if we'd followed the rules. So, now that the research is about to be published, Gaby and I have decided to put our professional lives on the line. We think you need to know.

My field is biochemistry, specifically neuropharmacology. I am (at least for now) a visiting fellow at the University of Hawaii, continuing a line of research I began as a post-doc at Iowa State. The goal of the work was to understand and, ultimately, manipulate the cycle of estrus in various domestic animals. Estrus is more popularly known as "heat" -- the fertile part of the female reproductive cycle, often accompanied by the release of chemical attractants called pheromones which produce the well-known reaction in the males of the species. Anyone who has owned an unspayed female dog or cat, or lives near someone who does, knows all about estrus.

The project was difficult and ambitious. Estrus is a very complex phenomenon that involves virtually all the major physiological systems. It is triggered by not one but several interacting biological clocks. It affects the endocrine system, releasing a flood of hormones which act as messengers to the brain, internal organs, and reproductive system. These in turn effect changes of their own. There are further influences from the external environment -- for example, the course of estrus varies considerably depending on whether (and when) copulation occurs.

Our project was successful, far beyond our original expectations. Building on a long line of research by others, we learned that there are several key brain chemicals--neurotransmitters--which regulate the cycle. My work produced a model, a mathematical description of the way these regulators function. It was the vital link, because it meant we had a tool to manipulate the process.

Five months into my fellowship, we synthesized a compound which could trigger estrus in our lab animals.

The implications of such a drug are enormous. For starters, imagine cattle which pump out three or four calves per year instead of one. Imagine racehorse owners who could bring their mares into heat on the one day they have access to a particular stud. Imagine show-champion dogs which could produce thousands, instead of dozens, of progeny. Imagine breeding new varieties of domestic animals in a fraction of the time, but without the unknown hazards of genetic engineering.

Our drug was effective on every animal we gave it to. The rats were first, then cats, and finally sheep and cattle. There was no change in the drug except its dosage. And it was that very general nature of the effect that got me into the argument with Gaby.

Gabrielle Mercer was a grad student, one of my research assistants. She spent most of her time (except for classes) in the lab, caring for the animals, giving injections according to the experimental design, and helping us write up the results. She was very good--smart, detail-oriented, conscientious and reliable. And she was very excited about the drug. She thought we should publish immediately, using our initial results in rats, without waiting for the large-animal data.

We were in the lab, in the rat room. We were watching a female that we'd dosed; she wasn't supposed to be receptive, but the drug had brought her into estrus and she was posturing, tail lifted, back arched, ready for mating. In nearby cages, males were alert, sniffing and scratching at the wire on that side. I was trying for the nth time to explain to Gaby why we couldn't submit our research for review just yet.

"But, Gaby, don't you see? It's the fact that we found a non-specific model that's important. Anybody can trigger estrus in rats by brute force, injecting massive amounts of the right hormones. But those approaches are all species-specific, and they have to be timed just right, and they don't tell us anything about the underlying process.

It's the fact that we have a general solution which works on any animal, at any time in the cycle, that demonstrates a true understanding."

"Sure," she answered, "but we already know that from the rats and the preliminary data on cats. The drug is totally different from any other approach we've seen in the literature. Why not get it into press and nail down our priority?"

"It isn't a contest, Gaby. We have to be thorough, and the large-animal results are the proof. It's only a few more weeks, and we can have the paper pre-written and ready to go. We'll just plug in the data and submit."

Gaby fumed. "Well, don't blame me if somebody else scoops us. Damn! You have your doctorate, but some of us still have reputations to make."

I grinned. "Some reputation. Gaby Mercer, who got her science career cut short by rushing to print with incomplete results. Really, Gaby, have a little patience! Besides," I said, "there's another thing that's been troubling me, and I want some time to work on it."

Gaby's eyebrows went up. "Oh? What's that?"

I should have told her to wait until I was ready. But I was getting used to bouncing ideas off her, and I plowed ahead without thinking.

"I want to run some human-model simulations."

Gaby's eyes went wide. Then she burst out laughing. "Whoa! That's a good one. You really had me going. I thought you were serious. Human model! Quick! Get the chastity belt, I'm going into heat!"

"All right, all right, don't fall out of your shirt. You think it's funny, but humans do have a reproductive cycle. Women don't have estrus, exactly, but you have a menstrual period. If this drug gets into the veterinary pharmacopoeia it'll be out there, in the environment, and humans will be exposed. In fact, I'll bet my stipend that somebody will try it on their girlfriend, or herself, just for a laugh. And right now we know exactly nothing about the potential effects."

Gaby's smile had faded. "OK, you're right. I'll help you." She grabbed my arm and dragged me toward the office and its workstation. It was my turn to laugh.

But three hours later neither one of us was laughing. The supercomputer on the mainland had run our simulation, and the results were confusing. Interpreted one way, the drug had caused little effect except a slight time-shift in the menstrual cycle. That alone was significant, because it meant we had a potential contraceptive. But another interpretation was possible. And now it was Gaby who was worried.

"It looks so much like the animal results. Don't you see? Look at the estrogen and progesterone curves. And what's this one? I don't recognize this compound at all," she said.

"I don't either, and that's probably an indication that we crashed the model. That can happen when you introduce something new and unforeseen."

"Unforeseen is right. But if you ignore that one element, everything else looks like our horny rats. How can that be? Humans don't go into heat!"

"It's not quite the same. The hormone ratios are all wrong. It could all be a side effect of the menstrual shift. Or it could just be a confused model -- probably that's all it is." I leaned back in the old wooden chair I favored for computer work, picked up a little vial of our magic drug.

"And are we so sure humans don't have estrus?" I posed, staring at the purplish crystals in the glass tube. "Maybe it's just more subtle. All the other primates have heat -- chimps, orangs, gorillas. We're not all that different." I pushed back from the workstation. "Come on, we need to get clear of this for a while. Let's go get some dinner. My treat." I slipped the vial into my shirt pocket.

Gaby and I continued our conversation in quiet tones as we walked down toward the beach. We had shared working lunches a few times, but I was always careful to keep our relationship strictly professional. That wasn't always easy, at least on my part. Gaby was no centerfold type, tall, a bit gangly, and rather plain in appearance, but she was attractive in many other ways -- very intelligent, enthusiastic and poised, quick to crack a silly joke. But she never showed any romantic interest in me, or any other man as far as I could observe. Or woman, either, I thought as we reached our goal.

Though on the beachfront, Micky's had never been on the tourist map. It was small and dark, on a potholed side street that ran down toward the shore, with only a tiny sign on the sidewalk to show it was anything but a rundown cottage. On the back side, though, there was a raised deck with a quiet bar, and inside were comfortable high-backed booths. Gaby and I headed for one of those.

"In one sense," I was saying as the food arrived, "humans don't have estrus because females are always in heat."

Gaby looked shocked for a moment, then grinned. "I never thought about it that way, but I can see it. With the possible exception of the menstrual period, women can and do have sex any time."

"Right, that's what I mean. Other animals have estrus periods, and they fuck ... er, copulate like crazy at that time. But the rest of the cycle they are totally indifferent to sex."

"The females are, that is. The males can be aroused at any time, as long as there's a female in heat nearby. Then they fuck her like crazy." Gaby grinned, and grinned wider as I blushed.

"OK, I guess it's silly to try to be completely clinical about all this. But you know I try to keep work separate from personal relationships."

"What personal relationships?" Gaby said. "You haven't had a date since you came out from the mainland."

I think I must have blushed again. "Funny how you noticed that." I held her eyes, and she met my gaze. "The same could be said about you. Between classes and your lab hours, there isn't much time for you to have a social life either." Gaby dropped her eyes and made a big production of eating her burger.

I steered the conversation back to safer territory. "Speaking of the males, what about pheromones? That's a big part of any estrus system. The females always emit a hormone which signals the males that she's ready."

Gaby took a drink of her coke, and said, "That's another argument against the idea that humans have an estrus cycle. If there were any substance that triggered that kind of primal response in human males, wouldn't we have found it by now? I mean, think of the market for a true aphrodisiac."

"You may be right there. Even if our remote ancestors had a pheromone response, we've probably lost that sense along with most of our sense of smell.

"Then again, I don't know. Pheromones are always highly species-specific and very complex molecules. We might not have stumbled onto it, even if it does exist. Or maybe it has been found, and suppressed as too dangerous."

Gaby looked skeptical. "You couldn't hide something like that. It would have to come out. Even if the first discoverer suppressed it, the next would report it, or the next..."

"Assuming it was easy enough for several independent researchers to find. And don't forget, the human research field is much slower because of the experimental protocols."

"True. And..." Gaby now looked very hesitant, pushed the pickle around her plate. " ... and if our drug does have a human effect..." She looked up at me. " ... how will we find out?"

That question hung in the air for just a few too many heartbeats.

Gaby broke into the background murmur. "There's no way we could get permission for human trials in time to find out before we're ready to publish."

Again it was Gaby who broke the silence. "If we publish this before we know, I mean really know, for sure..."

"Then," I said, "Pandora has opened the box. Only this time she had a pretty good idea what was inside before she did it."

Gaby continued to look at me with a questioning expression. We were interrupted as the waiter left the check. She was still looking at me when I looked back. It took me a minute to see where her train of thought was headed. Not wanting to hear the answer, I said, "So what do you think we should do about this?"

She didn't answer for a second or two. Then she leaned forward and reached into my shirt pocket. When she leaned back, her hand held a small glass vial containing purplish crystals.

"Gaby, that's absolutely crazy. Not to mention unethical. And foolish. We have no clear idea what the effects are going to be. You could do all kinds of damage, maybe destroy your reproductive capacity."

"We have to know," Gaby said.

I took a very deep breath. This was getting serious. "Even if we did it, the results would be unpublishable. Talk about ruining your career! Gaby, this is not Victorian London, and your name is not Jeckyll."

"You said yourself that the simulation we ran isn't useful, that this drug is too different for valid results. A human test is the only way."

"You know perfectly well that the result would be useless as data. There is only one subject, no controls, no protocol."

"But it would be one data point, which is infinitely better than zero, which we have now."

"All right. All right. But think -- if the model is valid, you're not likely to have negative effects, or much of any other effect as far as we can see. But if it isn't valid, as you're arguing, then you have no clue what the result would be. You could die, or have brain damage, or ... almost anything."

I reached for the vial. She pulled it back.

"We don't know how to interpret the model. Maybe it's perfect. Maybe it's way off. Either way, the numbers don't tell us what the drug does, subjectively. We need to know," she repeated.

"But wait. We don't even know the appropriate dosage, or how long the effects would last, if any. Gaby, I just won't let you take that kind of risk."

"You won't let me take the risk? Just who the hell do you think you are?" She was really angry. I had to keep calm and try to control this.

"I am the principal investigator on this project. I am your faculty advisor. I am your friend, I hope. And in each of those capacities, I'm telling you -- you must not do this."

Gaby's head dropped. Slowly she set the vial down on the table and pushed it across to me.

I left the vial where it was. "Thank you," I said.

But when Gaby lifted her eyes to mine, I saw that she was not yet ready to give in. "So, we're just going to go ahead. We're going to publish this, and the stuff will get out on the market, and then the whole human race will be the experimental subjects."

She had a pleading look. "Already there are environmental effects from pesticides and PCBs. Some of them are hormone mimics, and wildlife has been affected. They persist in the environment. They cause fetal abnormalities, interfere with reproduction. They're in humans, too, and may be having effects on us -- reduced sperm counts, birth defects, cancer.

"Tell me, Mr. Principal Investigator. What's going to happen when our little creation gets out there? And when they come to you and ask how you could have let this genie loose, what are you going to say to them? That the risk to your friend was more important than knowing the whole truth about your precious new drug?"

The waiter came and went with my credit card. Neither of us spoke while he was gone. When he brought the slip he refilled our water glasses. I was staring at that little vial. I was still staring at it when Gaby reached out, and took it, and unscrewed the top, and spilled a tiny pile onto her napkin.

"About three crystals, I think," I said. My voice sounded hoarse to my own ears. "Don't swallow, the stomach acids will degrade it. Under your tongue would be best."

"No. I think another moist mucous membrane would be more appropriate." Gaby carefully pushed three crystals onto her place mat and returned the rest to the vial. She stuck the bottle back in my shirt pocket. Then she moistened her fingertip and picked up the three crystals. She drew her hands back and dropped them below the table. Then I heard the rustle of her wraparound skirt, and she briefly arched her back. The rustle again. Then she was wiping her finger on the napkin. And staring straight into my eyes.

"How long do you think we'll have to wait before I show symptoms?" Gaby asked.

"Forever, I hope," I said. "Maybe you'll need a tampon a few days sooner."

"I hope you're right," she said. "Let's go out on the deck."

The ocean view was to the south. The rollers were coming in long and rumbly. We leaned on the railing, looking off to the right where the last of the sunset was dying. It was a warm night, with a soft and erratic breeze out of the west. Micky's wasn't too busy, three guys at the bar and a few couples at the outdoor tables. Canned music was playing, easy jazz, not the touristy Hawaiian that most bars played. It would have been romantic if I wasn't so worried.

"Gaby, I'm going to stay with you for the rest of the evening. If anything happens you may need somebody around who's not affected." I paused. "A long time ago, I ingested a few, um, substances myself. It was always good to have somebody around who wasn't high, just in case anybody freaked out."

"Thank you. I'm sure I'll be fine, but you can be an impartial observer. Anyhow, I don't mind your company. In fact..." She let the thought trail off.

If she was about to express some attraction for me, I didn't push it. Tonight I needed to be objective. That was not easy, with the tropical Pacific breeze stirring the stray hairs that refused to stay in her pony tail. Gaby sure looked good tonight. Why was that? Was it what she'd just done with the crystals? I reached out, touched her forearm.

She swung around to face me, a movement that lacked her usual unhurried grace. In the dim light I couldn't be sure, but her cheeks seemed flushed. She opened her mouth to speak, then just moved closer to me. She was beautiful, so beautiful...

Wait ... something was wrong. I shouldn't be thinking like that. But her breath was so warm, and coming so fast. My heart was pounding. I looked away.

Suddenly I was aware of the three guys at the bar, down at the far left end of the deck. They had stopped talking and were staring in our direction. They had very strange expressions. As I watched, one of them slid off his stool, unsteady on his feet but with his eyes never wavering.

I said, "I think we'd better get going." Gaby didn't answer. She had moved in, and was pressing against me, breasts and hips. I looked back at the bar. All three men were standing, and starting to move our way. I took Gaby's arm and steered her toward the exit.

I led her through the restaurant quickly. When we got to the street I looked back. The three guys had been joined by a fourth, and were coming through the door, looking around somewhat dazedly. Then they all stiffened, all four at once, and swung around to face us. I hurried Gaby along. She had her arms around me and was murmuring something into my shirt, but I managed to keep us moving.

It was five blocks to my bungalow. And the four men were following. And gaining. I felt an absurd twinge of fear and jealousy. She's mine! I held Gaby tighter and hurried her to the corner.

We turned right, and now the breeze was stronger and at our backs. We were less than half a block ahead when the guys reached the corner. I was almost to the point of panic, but Gaby didn't seem to have noticed them. I looked back again. They were still at the corner. But they had stopped, and were looking around, confused. In a dark spot between streetlights, I held Gaby still. The men at the corner looked around for a few seconds more, then turned and walked back toward Micky's. I heard halting voices and a burst of weird laughter as they moved off.

Now Gaby was rubbing herself against me, like some oversized kitten. The breeze died again, and I felt a surge of -- some sensation I can't name. I shook my head and got us moving again. The next thing I knew we were on the front porch of my bungalow.

Gaby was making noises, rubbing me with her hands and her body. I was fumbling for the keys. Suddenly there was a cloth flapping around me, and then it was gone, and Gaby was standing there in her panties and top, and she was untying the top, no, just pulling it aside, and oh my god what was happening to us?

The breeze came up and caught the skirt Gaby had peeled off. It blew down to the end of the porch and fetched up against the lattice there. My head was suddenly clearer and I got the key into the lock, got the door open, pulled Gaby inside. I flipped on the entryway light. One heartbeat later I was lost again. Gaby was on her elbows and knees. She had gotten one breast free of her top, its nipple swollen and hard, and she had one hand pressed firmly between her legs. She was making incoherent cooing sounds. And I was on my knees, too. I was pressing my nose into her crotch and breathing deep, deep.

Somehow I had gotten my shorts partway off. It was an enormous relief. My erection was painful, and feeling cool from its own wetness in the evening breeze. I had to get it warm. I had to get it into Gaby. I moved on top of her. I thrust between her legs--frustration! And again. I heard a deep-throated growl. It was my own voice.

The breeze blew down the hall. I lifted my head. Danger! I crawled to the still-open door behind us, slammed it shut. For one breath I knew what to do. I turned back to Gaby, who was fingering herself inside her panties, still kneeling with back arched and ass high. I grabbed that barrier of cloth and yanked hard. Gaby moaned. I yanked again. There was a tearing sound, and the remains of the panties were halfway down one leg. Gaby's crotch and thighs were slick and shining with her honey. I grabbed her and entered her with a single thrust. Together, we groaned with satisfaction.

Gaby was already coming, a frantic, grunting spasm brought on by her own strumming fingers and the sensation of being penetrated. And in two strokes I was with her, hammering my come deep into her wet, wet pussy. And so it began.

I have little coherent memory of the next hours. I know that we never left that entry hallway, and that we must have spent almost the entire time coupled. We both had repeated orgasms. Gaby's seemed almost continuous. I never lost that intense erection, not even after coming. We did not sleep. We weren't making love, we were fucking, coupling like the pre-human animals we had become, driven by instinct and need rather than desire.

What brought me to my senses was an urgent need to urinate. My erection had prevented that. I tried to get up and realized that Gaby was lying across my torso, one arm holding my leg, her mound pressed against my hip. She was awake, breathing normally, but when I stirred she gave a wordless protest and held me tighter.

I gently took her shoulders and brought her up beside me. Her top was still around her shoulders, but those firm little breasts had long since come free; her ruined panties were still around her left leg. She threw her arms around my neck and slung that panty-bound leg across me. My erection was nearly gone, and I had to get to the bathroom now. I disentangled myself, put down my hand and realized I was lying in a puddle of something. I staggered to the bathroom and relieved myself.

Those few seconds in the bathroom cleared my head immensely. I took a long drink of water from the tap. It was already full daylight, I realized. I took off my shirt, which was still in place but half-soaked in whatever it was. I wrung it out, then took a sniff. Immediately I was overwhelmed with sensations -- half-remembered images of Gaby, of me and Gaby, of thrusting, penetrating ... I dropped the shirt in the laundry basket and shook my head to clear it. I looked down at a new and rising hard-on.

Gaby was sitting up when I returned to the hall, holding her head in her hands and groaning. I left her there and went to fetch a bucket and mop. The puddle had to be urine, Gaby's urine. I couldn't have done it, and even under the circumstances we couldn't have produced enough sexual fluids to make that puddle. I had a vague recollection of Gaby, on all fours, letting go a stream against the wall, during one of the brief intervals when I wasn't in her. My god.

With the bucket filled I returned to our hallway. Gaby was standing unsteadily, legs too far apart, examining herself dazedly. I realized we both had several scrapes and bruises; Gaby seemed to be assessing the damage. She was covered with funk, her own and mine, sweat, semen, and piss. As was I.

She looked up as I approached. I couldn't read her expression. Maybe she was feeling some emotion that humans have never felt or named. I had no idea what to say. I set down the bucket, cradled her cheek in my hand, and kissed her. She threw her arms around me and returned the kiss.

"So now we know," she said.

"Now we know," said I.

Those were, I realized, the first coherent words we'd spoken since entering the house.

Gaby headed for the bathroom to clean up as I went to work with the mop. Each time I stirred up the puddle I got another whiff of the indescribable scent of her, and each time I got another surge of arousal. I dumped the bucket down the kitchen drain and got out the Lysol spray. I went over the hall with exquisite care. The erection subsided. I had a strange feeling of relief mixed with an ancient, primal sadness.

I went back to the kitchen to rustle up some food. I was famished, and only just realizing it. We must have burned a week's calories overnight. I piled a plate with anything I could find in the fridge and went looking for Gaby.

She was still in the bathroom. She had, apparently, drunk some water and cleaned up. She had removed the remains of her panties and top, and I finally saw her fully naked. I liked it. She was slender and well-proportioned, and the small breasts were perfect, red-brown nipples slightly upturned, lovely. Her hair had won its rebellion against the pony tail. As I watched she reached up, pulled off the elastic, gathered her hair and reapplied it. It was a small, domestic thing, and my heart sang to see it.

I offered her the food, and she gave a lovely little sigh as she grabbed for some grapes. I left the plate and went to my bedroom, thinking she might like a robe. Once there, I realized that her skirt was still out on the porch. I put on the robe and retrieved the skirt. Now, I thought, we'll just jump in the shower and be back to earth.

When I returned, Gaby was still in the bath. As I approached, I couldn't quite see what she was doing. The plate of food was still there, mostly uneaten. Gaby held something in her left hand, and was staring down at her right fingertip. There was something on the floor...

It was my shirt. She had pulled it out of the laundry basket. Her left hand was holding a small glass vial, its top unscrewed. The right fingertip was salted with a half-dozen purplish crystals.

"Oh, god, Gaby, no," I said. "Please God, no."

She looked at me with that unnamed and ancient expression, then dropped her hand and slid the right index finger deep into her pussy.

The higher dosage seemed to have a paradoxical effect. Or maybe we were just too tired from the first round. In any case, this time we seemed to be much more in control. We weren't limited to a doggy-style humping on the hall floor. Instead we used the bed, and the couch, and the kitchen counter, and the shower, and the recliner, and yes, the floor again. And I remember those ten hours very clearly indeed. Gaby was an astonishment. She was utterly insatiable, which was certainly an effect of the drug. But she was also playful, creative, and experimental. I can't say that we discovered any totally new techniques, but we certainly used a whole lot more than I had ever tried before.

We even managed to take a few breaks for other needs. I found that as long as I was some distance from Gaby I could lose the erection and take care of my bladder. We even ate a little, though nothing that took time to prepare.

Gaby spent at least an hour kissing, licking and sucking my poor abused cock, giving me a series of orgasms. I was no longer producing much semen, but the intensity of each peak seemed only greater for that. How Gaby did this while ignoring her body's own insistent demands for penetration I do not know. I can only say that I was literally incapable of returning the favor. As soon as my nose approached her pussy I was completely helpless; within a few seconds I simply had to stop, turn and enter her. She did not complain about this lack of sensitivity on my part. Instead, she just ground her hips to get friction on her clit, and joined me in coming, again and again.