This guide isn't supposed to be the tell-all story of the origins of life and evolution, but instead a gateway to the world of early Earth science and evolutionary biology. There is one theory that wasn't discussed: intelligent design. Intelligent design is the theory that life is too complex to have happened randomly, so it must have been created by some intelligent designer.
There is an ongoing battle between science and proponents of intelligent design over the origins of life. Science at its core is about taking observations, making hypotheses, and testing those hypotheses. Observations from those tests are then used to make new hypotheses, continuing the process. Observe, hypothesize, test, and repeat. Don't forget to rinse. All branches of science attempt to explain the natural world using the scientific method, including the study of evolution. However, the teaching of evolution continues to be a hot-button issue in some areas of the United States.
Many court cases have been fought over the right to teach intelligent design in schools, the most notable of which is Kitzmiller v. Dover Area School District. The case was brought up after a school board decision in Dover, Pennsylvania stating that intelligent design should be taught as an alternative to evolutionary theory, and that an intelligent design textbook be used as a reference for biology courses. The judge in the trial ruled that intelligent design was not science, and instead religion. Therefore, it could not be taught in the schools.
As discussed in this guide, there are many controversies in the evolutionary biology community: the neutral model of evolution compared to the selectionist model, the punctuated equilibrium model versus phyletic gradualism. Even Lamarckian evolution is making a comeback as evidence suggests that our experience affects the fitness of our offspring. Modifications of DNA that occur during our lifetime can be passed on to our offspring, and these modifications are a function of our behavior. Sounds Lamarckian.
Since there is some debate over the validity of Darwinian evolution, why is intelligent design not a valid scientific theory? Intelligent design isn't testable, and therefore doesn’t make use of the scientific method. The mantra of observe, hypothesize, and test isn't followed.
Many sci-fi films talk about the "next stage of human evolution." This is used to segue into explanations of mutant or alien creatures that are trying to wipe out humanity, or are trying to live peacefully with humanity while we try to wipe them out.
These common tropes in movies depict evolutionary theory in a nutshell. If you imagine that humans evolved some extra feature, these neo-humans will either be better suited for survival and will lead to reduction of humans in the population, or they will be weaker and we will try to wipe them out (either actively or passively). Mutant humans will struggle for survival against regular humans, and those best suited to their environment will survive.
This has already happened in human evolution, where Homo sapiens wiped out (or outbred) Neanderthal man (Homo neanderthalensis). We could expect that if there is ever evolution that leads to X-men, it would be at the expense of humans. The specific acquisition of teleportation, adamantium claws, or shooting lasers out of one's eyes doesn't appear to have a place in the gradualism of Darwinian evolution, but it sure is cool to watch.
Other movies such as Species and Planet of the Apes talks about how evolution of life that is superior to humanity will eventually lead to the subjugation of humans. While this is a frightening idea, this would only happen if we continue to hog all of the resources. As humans, we happily destroy natural habitats to build high-rise condos or private resorts. If there were super apes or some other species that was smarter than us, we can expect that they would demand the same resources that we currently use. Since we'd be fighting over the same environment and resources, we'd lose to the super apes.
Finally, if you think you'd like to try out natural selection for yourself, there are several games where you can wipe out some species. The most popular of which is the 2008 game Spore. In this game, you get to start from microbial life and evolve into beings capable of interplanetary life. Good thing this chapter's over. Go play.
Policy makers often consider how we can be stewards for the environment. Up until recently, the answer has been to destroy everything and hope that Bruce Willis saves us. As mentioned in the themes section, humans are responsible for mass extinction of numerous species of life. What is our role to preserve biodiversity?
Should the government promote preservation of species? If so, what species should we preserve? At what point does preservation of the species become a waste of money?
The preservation of the giant panda may be a perfect example of an organism facing extinction that is extremely costly. Millions of dollars are spent breeding pandas and preserving their habitat. This is all at the expense of species living in other biodiversity hotspots that are being destroyed. Despite what the movies might have you believe, none of those pandas ever learned kung fu.
Many scientists argue that the once-meat-loving pandas evolved to a bamboo-only diet because they feared competition from other predators. They sought refuge in the bamboo-rich vegetation of the mountains of China. There, they had to either learn to love the ample bamboo that nothing eats, or stay and scrap it out with the other animals.
Unfortunately, pandas are not adapted to live off of bamboo. They have to eat about half their weight in bamboo a day just to survive. Because they're so inefficient, all they can do is sit around, eat, and poop. Pandas poop about 40 times a day. Seriously. That doesn't leave a lot of time for mating. Since they have so few offspring, they are dying off as a species. Added to this is the human destruction of their habitat.
They might be expensive to keep around, but they are so cute. One would argue that adaptations making species "cute" leads to better survival, since humans try to preserve species. If you look at the World Wildlife Fund's website, many endangered species listed are generally cute and cuddly. They even use the panda as their logo.
The development of cuteness is an evolutionary adaptation in higher animals. It ensures that animal parents will take care of their offspring. This is why most baby animals are considered cute. Species that people consider to be "cute" will have a fitness advantage because we will try to protect them. We could call this "cuteness" selection. Meanwhile, there are no qualms over insect genocide.