"Changing Nature" is the seventh episode of the fourth season of the ABC sitcom Dinosaurs as well as the final episode of the series before its apparent cancellation. It originally aired on ABC on July 20, 1994, as the network series finale. The episode had an unexpectedly dark and depressing tone, which caught a lot of fans and critics off-guard.
The final episode deals with nature being thrown out of balance due to the extinction of a bug species called Bunch Beetles caused by the corrupt company WESAYSO, whom the main character of the series, Earl Sinclair, works for. To fix the problem WESAYSO has formed a task force with Earl as chairman in charge of the task force. However, after multiple attempts to fix the problem, Earl only winds up making the problem worse and causes the Ice Age.
Plot
The Sinclair family is celebrating the upcoming arrival of the Bunch Beetles, a species of insect who come to Pangaea annually to eat all the cider poppies which tend to grow excessively around spring. However, after the countdown, the Beetles don't return, much to the confusion of everyone. Four days later, without the Bunch Beetles, the cider poppies have completely grown out of control and are overtaking Pangaea.
As the Sinclairs and Earl's best friend, Roy, try to deal with the situation by trimming down the cider poppies, one of the Bunch Beetles named Stan unexpectedly arrives at the Sinclair's house. He explains that he became lost on his way to the mating ground (in a swamp), but he needs to get there now since Bunch Beetles have a short lifespan. Charlene volunteers to help Stan but when they get to the swamp they discover that FruitCo, a subsidiary of the WESAYSO corporation has built a wax fruit factory over the mating ground's swamp. They also learn from one of the factory workers that all Bunch Beetles who arrived at the factory have been sprayed with insecticide, causing the entire species to become extinct thus making Stan the last of his kind.
Charlene reports the extinction of the Bunch Beetles on DNN (Dinosaur News Network) and even points out how the WESAYSO corporation is also responsible for the cider poppy crisis. But Earl takes over the interview and tries to defend the company's actions by claiming that it was all in the name of progress. B.P. Richfield watches the interview from his trailer after getting a call from his boss, knowing that it could spell trouble for WESAYSO's public relations. Intrigued by Earl’s comments, he decides to have Earl be in charge of a task force to fix the problem.
When Earl and Roy are being interviewed about the task force, they explain that they're going to spray the cider poppies with defoliant and assures reporters that it is safe, even though it was donated to them by B.P. Richfield who prefers to remain anonymous. Robbie questions Earl about spraying the continent with poison and asks if there is a safer alternative. Charlene suggests that they trim back the vines and try to live with them for a while until nature restores the balance, but Earl refuses, claiming it will take too long. The defoliant is sprayed, which gets rid of the cider poppies, but the next day it is revealed that not only are all the cider poppies gone; but all plant life on Pangea has been killed too, resulting in a famine. Earl then reassures his family that Mr. Richfield has found a way to bring back the plants.
In Richfield's office, he, Earl, and Roy try to figure out how to revive the plants. Richfield states that they have to make it rain and in order to do so, they need clouds, which he thinks come from volcanoes (which actually produce smoke). Richfield states that in order to make clouds they need to set off a bunch of volcanoes by dropping bombs in them. Earl is reluctant since their last idea failed, but is convinced by Richfield not to lose faith in progress and they all go with the plan.
Soon, bombs are dropped into volcanoes all around the world, which create giant thick black clouds that cover the entire planet. Earl thinks the clouds will create rain, but the rest of the Sinclair family doubt that will happen. On the news, newsanchor Howard Handupme reports that the clouds are blocking off the sun and causing global temperatures to drop precipitously. Earl tries to stay positive, claiming that the sun will come out and melt the snow, making the plants grow. But Howard reports that due to the thickness of the clouds scientists have predicted that it will be tens of thousands of years before the sun shines over Pangaea again, thus creating the Ice Age. Earl calls Mr. Richfield about the problem, but Richfield refuses to listen, claiming it is a good thing because everyone is panic buying WESAYSO's products.