Growlithe and Arcanine

"Today, students, we have two rare fire pokemon," said the professor, who seemed not to notice the redundancy of his statement. The man gestured, and the curtain withdrew, revealing a very large growlithe, slightly above waist level, and a fanged, sinuous arcanine that was slightly larger then normal size. The growlithe's cage was simple, even flimsy, much like the cages of the dragon pokemon displayed earlier that week. The arcanine's was much stronger, and was clearly an actual way of restraining the pokemon within.

"Arcanine, as a stone evolution, were rare when the pokemon first escaped Giovanni's lab. The ten arcanine could not interbreed with growlithe, and they had to look long and hard for wild arcanine. This meant they did not immediately infect the wild population with the no-evolution genes. Meanwhile, the escaped growlithe began to infiltrate the wild growlithe population, further reducing the number of available arcanine.

"At first, it appeared that the growlithe, like the vulpix, would become the dominant species despite the fact they were basically just weaker versions of their evolved form, like charmander and charmeleon. However, the gyarados changed that.

"When the gyarados began to go on their rampage, fire pokemon were slaughtered. Arcanine were stronger and faster, so their mortality rates were lower then the growlithe. Also, the places they inhabited, like charizard, were not places that gyarados liked. The growlithe, unable to compete for the better fire-type areas, often ended up on land too close to water. When the first wave of destruction was over and the survivors breeding more powerful pokemon, the arcanine were no longer vastly outnumbered.

"But that would not have been enough. Like the ninetails, there were too few arcanine. They were unable to meet each other and reproduce as fast as the growlithe. Unfortunately for the growlithe, the nature of their packs spelled their doom.

"After the gyarados, the growlithe and arcanine formed tight packs, unlike the looser, almost herdlike ones before. Only the alphas had any children. These alphas, as the strongest, would be arcanine if there was one in the pack.

"At first, only a few arcanine leaders existed. They would choose a second arcanine as their mate, and their children would, rather then stay in the pack, go out and displace a growlithe alpha. The growlithe almost stopped reproducing at this point, and within a generation were nearly extinct.

"The only remaining ones were in intensely xenophobic packs that refused to admit any arcanine. At first these packs were killed off by the other pokemon, because there was fierce competition for lands not near gyarados. However, because only the strongest were reproducing and the high mortality rate, the growlithe's rate of change was slightly faster then the arcanine's. They've scarcely begun to boost their population, because like charmander and charmeleon, the growlithe are simply weaker versions of their evolved form, with no special traits of their own, but they are able to survive."

A student called out, "Why didn't the same thing happen to the houndour?"

"While I won't go into detail," said the professor, "It seems like the xenophobia instinct never activated in them. So when their packs formed, the houndour stopped reproducing entirely."

"Why do the Jennies still use growlithe?" called out another student. "Instead of electric or at least arcanine?"

"Well, the Jennies traditionally used growlithe and arcanine, and have a natural affinity for the two species. Unlike the growlithe, however, arcanine are wild, aggressive creatures who are very hard to train. Most of the living growlithe belong to Jennies or are in some way connected to people. While they aren't as strong, they are some of the most loyal pokemon, and are not as bloodthirsty as most pokemon are."