Let's talk extinction. Almost every organism in the history of the world has gone extinct. There are few things in this world that are guranteed, death is one of them, every living thing will eventually meet it's demise, and in a broader sense to fit this SLO, extinction is one of those things that is guranteed. From trilobites, to the dinosaurs, to a plethora of other species, extinction is the end all be all, their time simply expired. So, with all this considered, let's take a turn down a morbid street and talk about human extinction. Is it possible and what are some things that could lead to our extinction? Have we come close before? How else have other species gone extinct and can we avoid the same treacherous path they went down?

Oh yeah, 100%. In fact it really isn't a matter of if we will go extinct much like everything before us, but a matter of when we will go extinct. "In most countries—including poorer ones—the birth rate is now well below the death rate." (Gee). So, obviously when you think of extinction of the human species a common thought is going to be overpopulation. This goes back to Germany in WWII Lebensraum, or living spaces was the idea that superior nations had to evolve and take advantage of the finite resources we have here on earth. This is a concern for human population, what if we used up all of our living space and ran out of the finite resources we have here on earth and faced extinction? Well, the good news is, this isn't necessarily going to happen, because scientists now fear that we may face underpopulation. In many countries around the world, the death rate has began to surpass the birth rates. Another problem when it comes to the human species is we do not have enough genetic variation, "Thus were sown the seeds of humanity’s doom: the current population has grown, very rapidly, from something much smaller. The result is that, as a species, H. sapiens is extraordinarily samey." (Gee). Another reason that humans will eventually face extinction is something called extinction debt. This is the idea that eventually every dominant species will use up the available resources in it's habitat and once that happens, it will cash in on it's extinction debt and it will be time for the species to go extinct. In the case of humans we can look at all the natural resources that we are using such as soil, that will eventually dry up and we will be left with nothing.

Throughout history there have been multiple times where humanity has come face to face with extinction and battled through it. The earliest evidence that I could find of humans being on the brink of extinction was roughly 195,000 year ago when the earth entered a glacial stage called Marine Isotope Stage 6. "While the planet was in the grip of this icy regime, the number of people plummeted perilously—from more than 10,000 breeding individuals to just hundreds." (Marean). Humans ended up surviving this by living on a coastline in Africa that was still warm enough and bountiful enough to support them through the trying times. Another time that humanity found itself on the brink of extinction was about 75,000 years ago when the Toba Volcano in Indonesia erupted. " According to scientists, this volcanic eruption was the largest in two million years. It is said that around 3,000 cubic kilometers of ash was released during the event which unleashed millions of light blocking particles in the atmosphere killing plants and trees." (Malik). Thanks to all the ash in the air their was little to no rainfall and this also led to food shortages but somehow we managed to pull through. My favorite however when it comes to times we've almost gone extinct is by our own hands with nuclear warheads. Everyone assumes that we will end up going extinct by our own hands and this was on full display during the cold war. One such example is when things got extremely close to hot when Russia placed nuclear warheads in Cuba and had them pointed directly at the U.S and the U.S had warheads in Turkey pointed at Russia. It is belived that it would only take about 10-100 nuclear bombs to bring the entire human race to an end, and many times during the cold war and shortly after it seemed liek it may be a very real possibility. In 1995, American scientists had launched a rocket carrying science equiptment and the capital city of Russia was in it's flight path, and it was all hands on deck at the Russians prepared for all out nuclear war with the U.S. " Immediately, a signal was sent to ‘Russia’s nuclear briefcase’ which had a ten minute decision deadline. Russian President Boris Yeltsin activated the nuclear keys and orders were given to be ready for a war against the United States of America." (Malik). Thankfully for all of us, the rocket fell into the ocean mere minutes before all of humanity was wiped out.

So, there have been six major extinctions throughout earth's history. Things tend to go full circle, so there is a chance we may get hit with one of these big extinction events, and when we do, will we be able to stop or reverse it? One of the extinction events I want to look at is The Great Dying. This occured around 225 million years ago and the exact cause is unknown but there are a few guesses, " This extinction is thought to be the result of a gradual change in climate, followed by a sudden catastrophe. Causes including volcanic eruptions, asteroid impacts, and a sudden release of greenhouse gasses from the seafloor have been proposed..." (AMNH). So, the events that led to this extinction we my actually get a chance to see in our own time. There has been a gradual change in climate over the past century or so, and an excess of greenhouse gasses are released into the atmosphere every day from the vehicles we drive to the food we make, and a plethora of other things. I belive that it is possible to turn this around, if we plant trees to help increase the carbon dioxide on the planet and find alternatives to fossil fuels, we still have a real chance to change course and maybe avoid repeating history. The next extinction that I wanted to look at was the one that killed the dinosaurs, the Cretaceous-Paleogene Extinction. This is the big one that we all know about, a big asteroid hit the earth and completely wiped out all non-avian dinosaurs. The good news for us is that Nasa is looking out for us. They are working on what they call a double asteroid redirection test or DART for short, which would help them redirect an asteroid if it were coming towards earth. Even if one were to hit, we're a lot smarter than the dinosaurs and we would be able to find a way to get to safety and if the majority of humanity was wiped out, we could always return to our hunter-gatherer ways as we started our evolution all over again. The last extinction I wanted to talk about is the one we are currently living through, the Holocene Extinction. Over the course of the last 10,000 years or so, there has been a constant string of species that have been going extinct. Thanks to humans, climate change has been wiping out species as well as introducing invasive species that destroy habitats, as well as destroying habitats for their natural resources. Only time will tell if we'll be able to beat this exctinction event or not.

AMNH. “Episode 12: Six Extinctions in Six Minutes.” Episode Twelve: Six Extinctions in Six Minutes , https://www.amnh.org/shelf-life/six-extinctions.

Gee, Henry. “Humans Are Doomed to Go Extinct.” Scientific American, Scientific American, 30 Nov. 2021, https://www.scientificamerican.com/article/humans-are-doomed-to-go-extinct/.

Gill, Prabhjote. “For an Asteroid to Wipe out Humans, It Has to Be Bigger than the One That Killed the Dinosaurs.” Business Insider, 29 Aug. 2019, https://www.businessinsider.in/asteroid-hitting-earth-and-ending-life-has-to-be-bigger-than-the-one-that-killed-dinosaurs/articleshow/70893317.cms.

Malik, Yaruq. “5 Times When Humans Came Close to Extinction.” Dunya News, 7 Apr. 2016, https://dunyanews.tv/en/SpecialReport/331259-5-times-when-humans-came-close-to-extinction.

Marean, Curtis W. “When the Sea Saved Humanity.” Scientific American, Scientific American, 1 Aug. 2010, https://www.scientificamerican.com/article/when-the-sea-saved-humanity/.

Petruzzello, Melissa. “6 Animals We Ate into Extinction.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., https://www.britannica.com/list/6-animals-we-ate-into-extinction.

Tilman, David, et al. “Habitat Destruction and the Extinction Debt.” Nature News, Nature Publishing Group, 1994, https://www.nature.com/articles/371065a0.