Outside, the squall was really kicking up its heels. The rain drops had turned into solid sheets of water slapping against the house. The roof and walls creaked with long, complaining sounds. Inside him, Ed felt other walls begin to strain against a storm made of nothing but emotions.
He shoved his chair back and lifted his hand out from under Danette’s so he could walk to the windows. Watching the curtains of rain ripple in the sparse street light was easier than watching his reflection in her eyes.
“The deadly waters roll...” he murmured the words to an old lake song as a fresh wave of rain smacked against the windows.
Behind him, Danni sighed. “But the waters aren’t deadly anymore, Ed. We took care of that. No pesticides, no road salt, no acid rain....”
Ed turned slowly around.
“My God,” he whispered. “The waters!” Before he knew what he was doing, he snatched the car keys off their hook and ran out into the rain, barely aware of Danette matching his stride.
It was a bad night to be driving too fast and Ed almost put them in the ditch a half dozen times before they’d gone three miles.
“You want to tell me what’s going on?” Even in the dim light, he could see how white Danette’s knuckles were where she clutched the dash. He didn’t take his foot off the accelerator.
“What’s going on is we’ve been idiots. With Jerry’s legacy of graphs and biological magnifying glasses, we’ve forgotten that Nature has its own agenda.” He skidded into the station’s parking lot, raising a spray of water under the tires. “Nelson was right. The lake was waiting for its chance to do it to us.”
“Ed....”
“Danette, the algae isn’t the bottom of the chain in the lakes. The water is. The one factor in the equation we have completely changed is the water. All of it. The lake water, the sea water and the rain water.”
Danette’s eyes widened and Ed knew he didn’t have to say another word. They dove across the parking lot hanging onto each other to keep their balance on the slick pavement. Danni caught Ed’s key card as it slipped from his fingers and shoved it into the reader. The door latch clicked open and they dashed side-by-side for the lab.
“What the—” demanded Doug and Marcy in a perfect chorus as Ed and Danette burst into the lab. The students were both bent over microscopes, each with one hand hovering over their keyboards.
“How do you get the weather service up on this thing?” Danni plunked herself down in front of the phone board. “We need to know where this squall is coming from.”
“Doug, lend her a hand. Marcy, grab these.” Ed hauled open one of the cabinets and began loading beakers into Marcy’s arms. “Come on.” He scooped up three more beakers and headed for the door.
“Watch the water.” He was grateful for his own sealegs as he duck-walked over the puddles he and Danette left on the floor.
“Ed, if it’s not too much trouble...” Marcy’s shoes squeaked loudly on the tiles as she struggled to keep up with him. “What are we doing?”
“Getting a sample. It’s got to be clean or I would’ve used a bucket at home.” Ed shoved the outside door open with his shoulder. A fresh load of rain soaked him to the skin all over again.
Marcy, to her credit, followed him out into the storm without hesitation. The rain plastered her hair to her scalp in an instant. Ed set his beakers down on the sidewalk and then took hers to set beside them.
“You’re collecting the rain?” she said, bewildered.
“Right. The lake’ll be there tomorrow. We can get a water sample and a fresh catch of fish as soon as the weather clears, but we need rainwater too.” Ed kept his gaze on the beakers. The fat drops pinged and clattered onto the glass making a chaotic noise, like someone shaking a dozen jingle-bells.
“Come on, come on,” he muttered as water began to collect inside the beakers.
“Ed.” Marcy tapped him on the shoulder. “I know I’m supposed to play the dutiful protege here, but, if you don’t mind me asking—”
“Ed!”
Ed jerked his head around. Danni leaned half-way out of the station door. “We got it! The storm’s coming in from across Quebec. I’ve got Doug downloading the weather patterns for the last two years. I could get to like this grad student thing!”
Ed grinned at her. “Make sure he gets the acid rain levels for that same time frame!”
“Excuse me!” shouted Marcy. “Why in God’s name has my doctoral professor got me standing in the pouring rain?”
“Selection pressure.” Ed squatted down and inspected the beakers. Three were almost a quarter of the way full.
“What?” The shrill note in Marcy’s voice penetrated his attention all the way. Ed wiped at the water streaming down his cheeks and straightened up.
“That’s what’s killing the fish. That’s where your algae went. Darwin took them out and Superior swallowed them.”
“Dr. Nickerson—" began Marcy.
Ed picked up one of the beakers and squinted at the measurements. “I think we’ve got enough. Grab some, will you?” He wrapped his big hands around four of the beakers and carried them back towards the station. “And don’t drip in them.”
Marcy groaned, grabbed the remaining beakers and, holding her head carefully so her long hair dangled over one shoulder, followed him back into the lab.
“Dr. Washington...” Marcy pleaded as they passed Danette.
Danette relieved Marcy of two of her beakers and fell into step beside her. “As soon as the TDS fish were released into Superior, natural selection started in on them. Survival of the fittest. The fittest being, among other things, the fish that were best able to convert the TDS algae into energy." She backed up against the lab’s door and waited while Marcy went in first. “The same holds true for the algae. The fittest algae would be the algae that could convert the most dioxin into usable constituent chemicals without dying.”
Marcy deposited the beakers on the lab counter. “So the populations of fish and algae that had the best connection with the symbiote would do the best, because their respective digestive systems would be able to filter more food out of the poison.”
Marcy looked across to Doug who was still at the phone board. Doug shrugged at her and tossed a towel over the counter.
Marcy caught it and began rubbing her face dry. “I don’t want to be rude, Dr. Washington, but we knew that.” She toweled off the ends of her hair.
“Ah, but natural selection doesn’t aim for ‘the best.’ ” Ed began carefully pouring rainwater from the beaker into test tubes, ignoring the water running down the back of his neck and dripping from his jeans into his shoes. “It just aims for ‘good enough,’ and ‘good enough’ means good enough to produce babies under the existing environmental conditions. The species that has the most offspring that produce offspring, wins.
“Now.” Ed shoved a rubber stopper into the test tube’s mouth. “You just said that in Lake Superior, as it stood twenty years ago, the species that would have the most offspring would be the species with the most efficient link to the symbiote.” He turned to both of the students. “But selection was also going on for the TDS symbiote. The symbiote variant that would be most successful would be the one with the healthiest hosts because healthier hosts would be more likely to breed, and pass more of the symbiote on to the next generation. So the variant that could seek and find the most toxins in the host system would be the winner. Now, where are toxins, dioxin specifically, held the longest in a living body?”
“Fatty tissues,” said Doug promptly. “Oh my God. ...”
Marcy’s lips moved silently while she tried to work out what was coming next. “So when there wasn’t enough toxin coming through the fish’s digestive system from the lake water—”