“That’s great, but what does that mean?” Sanders said. It was clear Aparna was going over his head more than a little bit.
“Basically, if they don’t pick up the right parasites from their environment, certain developmental stages can’t happen,” Aparna said. “In the case of the nuclear chamber, a developing kaiju has to—among many other things—acquire the sort of parasite that acts as an internal cooling system from the kaiju, bringing in air from the outside and routing it through the kaiju to take away heat. Gaining those parasites creates the conditions that allow the kaiju to grow larger. Growing larger introduces stress on the developing kaiju because its ability to continue living through metabolic functions alone quickly decreases. That type of stress causes the kaiju body to release specific hormones and initiate other processes that, among other things, create and activate the nuclear chamber.”
“And if they don’t find the right parasites?”
“Then they don’t become kaiju. Either they die from growing too large—they fall victim to the square-cube law”—Sanders frowned here, which I assume meant he’d never heard of that particular law—“or they simply stay at an earlier stage of development. It’s not quite right to think of the massive kaiju as the only viable stage of the creature. They can live quite happily at earlier developmental stages for their entire lives, where they are ‘only’ as large as, say, an elephant or a tyrannosaurus rex. Only a small percentage of all kaiju actually get to what we would consider true monster size.”
“So, if you want a kaiju, you need some parasites,” Tipton said.
Aparna nodded. “And not only some parasites, specific parasites, for specific species of kaiju. One of the really interesting things about Bella, and Edward, the kaiju who impregnated her, is that they are in the wrong place. Their species is endemically from what we’d think of as Mexico and Central America. There are some parasites critical to their development that don’t exist this far north. Which means they had to have come here from the south as fully developed kaiju, because they wouldn’t have been able to develop here.”
“What does that mean for their children?” Sanders asked. “Will they develop into full-size kaiju?”
“It depends,” Aparna said. “If Bella stays in the area as they develop, or if they can get close to Edward without him or some of his parasites eating them, then they might get those critical creatures from them and grow into large kaiju. If Edward and Bella leave, they’ll stay at an earlier development level. Mind you, most of them won’t even get that far.”
“They’ll get eaten, you mean.”
“Yes, or they’ll starve. The kaiju at every stage of life are predators, and the larger they get, the closer they get to their ecological apex niche. An ecological system can support only so many predators. And when you have a full kaiju in the area, things get even worse.”
“Why?” Tipton said. “They’re nuclear powered. They’re beyond eating.”
Aparna shook her head. “They derive energy from their nuclear processes, but they still need things like nutrients for their biological systems. They still hunt. They hunt other kaiju. They hunt less-developed kaiju. But more significantly from an ecological point of view, they also have their legions of parasites, many of whom hunt, and all of them have metabolisms. A kaiju is a walking mountain of mouths. They and their parasites can and will eat their local countryside bare. Or would, if the countryside didn’t fight back.”
“It fights back?” Sanders said.
“Oh, yes,” Aparna said. “Everything here is ridiculously lethal, because all of it that’s not a kaiju parasite has evolved to defend itself from kaiju parasites. Some things even prey on the parasites directly. It’s constant war. Sometimes the countryside even wins, and routs the parasites.”
“And then what happens?”
“Well, remember: The kaiju aren’t animals, they’re ecological systems,” Aparna said. “What happens when you kill off a critical part of an ecological system? Chances are good the rest of it dies, too.”
“It’s this intense competition that makes this version of Earth so interesting, from a chemistry point of view,” Kahurangi said, in the next scheduled meeting, where he was briefing Sanders and Tipton in the latest from the chem lab. “Everything is signaling to everything else, and most of it is some variation of ‘Leave me alone or I’ll cut you.’”