Hey there! I’m Kate from MinuteEarth. It’s pretty amazing that humans and other complex life forms exist on Earth. It all started with simple life forms that appeared around four billion years ago. These early life forms found ways to survive and reproduce, and over time, they evolved into the diverse species we see today.
But here’s something interesting about evolution: most species actually go extinct. More than 99% of all species that have ever lived on Earth are now gone, like the dodo and the giant ground sloth. So, what makes a species survive or go extinct?
My friend Jasper has created something cool to help explain extinction: The MinuteLabs Evolution Simulator! This simulator lets us see how different situations can lead to extinction. It starts with life forms on a board with food pellets scattered around. These life forms have traits like speed and size that can change with each generation. They need to find food and return to the edge of the board before running out of energy. If they succeed, they reproduce, passing on slightly different traits to the next generation. This is a simple version of how genetic mutations work.
Jasper found that how quickly the environment changes can affect whether a species survives. If the environment changes slowly, species can adapt over time. But if changes happen too fast, like a sudden drop in food supply, species might not adapt quickly enough and could go extinct. This happened to ferrets when their food supply suddenly decreased due to human activities.
In nature, species often compete for the same resources. Jasper’s simulator can show what happens when two species compete. For example, if one species is faster and another can see farther, they can coexist as long as there’s enough food. But if food becomes scarce, one species might outcompete the other, similar to how dingoes outcompeted Tasmanian tigers when prey became scarce.
Predation is another factor. If a large predator is introduced, it can quickly wipe out smaller species. In the simulator, if there’s no size variation, life forms evolve into larger ones that consume everything, including their neighbors. This is similar to how invasive species can dominate native ones, like when brown snakes were introduced to Guam and led to the extinction of native bird species.
Humans often change the environment faster than species can adapt, leading to extinctions at a rate much higher than in the past. However, natural events like meteors and ice ages have also caused massive extinctions.
Sometimes, extinction can happen without any major event. In the simulator, life forms might thrive for hundreds of generations, but sometimes they suddenly die off due to small, random changes. This shows how luck can play a role in evolution, especially for species with small populations.
As species evolve over many generations, they can become very different from their ancestors. This raises the question: when do they become a new species? For example, modern cows evolved from wild oxen, which are now extinct. But cows are thriving, showing that extinction isn’t always a dead end. The first life forms likely went extinct, but not before evolving into new species, leading to the diverse life we see today.
If you’re curious about the Evolution Simulator, you can find it at minutelabs.io, along with other fun labs. There’s also a video on the MinuteLabs YouTube channel that explains how the simulator works.
Thanks to The Great Courses Plus for supporting this video. They offer a library of over 11,000 lectures, including a course on “Major Transitions In Evolution,” which explores life’s journey from the first life forms to modern humans. You can get a free trial at TheGreatCoursesPlus.com/minuteearth. Happy learning!
Visit the MinuteLabs Evolution Simulator online. Experiment with different traits and environmental conditions to see how they affect species survival. Try to create a species that can survive multiple generations. Discuss your findings with your classmates.
Draw a food web that includes various species and their predators. Identify what happens when one species goes extinct. How does it affect the rest of the web? Present your food web to the class and explain the impact of extinction on the ecosystem.
In groups, create a role-playing game where each student represents a different species. Introduce environmental changes and challenges, such as food scarcity or new predators. Decide which species survive and which go extinct based on their traits and adaptability.
Choose an extinct species, such as the dodo or the Tasmanian tiger, and research its history. Present a report on why it went extinct and what could have been done to prevent it. Share your findings with the class in a presentation.
Participate in a class debate on the role of humans in species extinction. One side argues that human activities are the main cause of modern extinctions, while the other side argues that natural events are more significant. Use evidence from the article and other sources to support your arguments.
Sure! Here’s a sanitized version of the transcript:
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Hi, this is Kate from MinuteEarth. The fact that we humans – or any complex life forms – exist on our planet is kind of amazing. Somehow, the simple life forms that appeared four billion years ago found the resources they needed to survive and reproduce, and their offspring continued this cycle. Those early life forms evolved and diversified to occupy pretty much every nook and cranny on Earth.
But here’s evolution’s lesser-known fact: mostly, species go extinct. More than 99% of the species that ever evolved on Earth have disappeared, like the dodo, the giant ground sloth, and billions of other species. So what determines whether a species survives or not?
[Jasper] Psst! Kate! Hey Kate!
[Kate] Oh… hi Jasper… can this wait? I’m kind of in the middle of a video…
[Jasper] I know – sorry to interrupt! But I built something that might help illustrate this whole extinction thing: The MinuteLabs Evolution Simulator! It’s based on the early life forms created by our friend Justin from the Primer YouTube channel, and I’ve spent the last few months making it interactive.
[Kate] So…
[Jasper] … did I mention the viewers can see it at www…
[Kate] Jasper! Can you at least wait until the end of the video?
[Jasper] Right! Sorry, I’m just excited.
[Kate] Okay… so how does this help explain extinction?
[Jasper] Well, we can use it to show different situations that result in total extinction! We start the simulation with life forms on the edge of the board and a certain amount of food pellets sprinkled around. The life forms all have particular traits that can change with each new generation – like speed, size, and ability to detect food – and they move around the board trying to find a pellet of food and get back to the edge before they run out of energy. Any life form that finds two pellets before running out of energy will reproduce and create a new life form with traits that are slightly – and randomly – different. It’s a simplified version of genetic mutation. I think it’s fascinating to see how the traits of these life forms change over time… and whether they survive at all.
[Kate] Oh, okay, cool! So what have you found out about population declines?
[Jasper] Well, I found that the main cause of a population surviving or declining was often a result of how quickly the environment changed. For example, if I decrease the amount of food available significantly over several generations, the traits of the population can change fast enough to compensate for the lack of food. But if the change happens too quickly – like if I reduce the food available in a single generation – the population won’t have enough time to adapt, and they all just die off.
[Kate] Okay, interesting. The same thing happens in the real world… take ferrets, which can generally deal with fluctuations in their favorite foods, and their diets often change over time as their environment changes. But when a sudden drop in their food supply occurred due to human activity, the ferrets couldn’t adjust quickly enough and went extinct in the wild.
Of course, in nature, there are usually a few species competing for the same food… any chance your simulation can handle more than one species?
[Jasper] Actually… I just added that feature!
[Kate] And?
[Jasper] Well, let’s try it… here’s a simulation with two species; the orange ones are faster, but the blue ones can see farther. As long as the amount of food remains the same, they can coexist for quite a long time. But… wait… let me try something… if I suddenly reduce the food supply, all of a sudden the blue species start to take over and the orange ones decline.
[Kate] That’s just like Tasmanian tigers and dingoes!
[Jasper] Wait, what?
[Kate] Well, those two carnivores used to coexist without too much trouble, even though they ate more or less the same food. But when human activity decimated the available prey, the dingoes, which were stronger and hunted cooperatively, had an edge in finding scarce food, so they ended up surviving while the Tasmanian tigers couldn’t get enough to eat and went extinct on the Australian mainland.
[Jasper] Oh, that reminds me! Predation can also be a factor in extinction, like when a large predator is introduced into a board filled with smaller life forms. Any life form that is at least 20% bigger than another can eat it. If there’s no initial variation in size, life forms will slowly diversify into larger ones that quickly consume any available food – including their neighbors – and smaller ones that search for leftovers. If I start off with a world of small life forms and introduce even a single large predator, it will quickly decimate all the smaller life forms in just a few generations.
It seems that if the blue life forms had a chance to coevolve with the larger species, they might have had time to adapt and avoid being eaten, but things happened so fast they didn’t stand a chance.
[Kate] Exactly! Those poor little life forms. This is what we see so often when invasive species dominate native ones. Take snakes and birds, which are species that coexist all the time – assuming the birds evolved with the snakes and know to be wary of them. But when a single brown snake was introduced to Guam, in just a few years, it and its descendants killed off 12 native bird species.
[Jasper] Hmm… I’m starting to see a pattern… it seems like all the extinction scenarios you’ve brought up happened because of us humans.
[Kate] Yeah, I mean, we humans tend to change things at a speed that evolution just can’t keep up with. As a result, species are going extinct at least ten times the historical rate. But we aren’t the only contributors – massive events like meteors and ice ages also seem to cause huge extinction events.
[Jasper] But, at least for life forms, sometimes it seems like extinction can happen without any grand event at all… look at this: Sometimes, when I run this simulation, these few life forms happily reproduce for hundreds of generations. But other times – when I keep the exact same parameters – they suddenly all die off in a few generations, with no interference at all!
[Kate] That’s what’s so interesting about evolution! Sometimes, whether a species flourishes or fails can come down to luck. We know that, especially for certain kinds of animals – like those that naturally exist in low numbers and have large home ranges – small, random changes can kill off an entire species.
[Jasper] Ugh, that’s a tough one to consider. I have one last thought that’s maybe a bit philosophical… The simulator can run for a long time, and the population can keep evolving for hundreds… or thousands of generations. But by the time the life forms are on their 600th generation, they are really different than when they started. If we color the life forms a brighter shade of red the faster they are, you can see that they become much faster and larger than they were at the start. So… are these life forms a new species? And, if so, did the old species go extinct?
[Kate] I mean, maybe? One of the really interesting things is that extinction isn’t necessarily about failure. Like, modern cows have changed so much since they descended from a kind of wild ox – they’re smaller and have much larger udders – so the two are generally considered to be totally different species. And since there aren’t any more wild oxen, we consider them to be extinct, while cows are still thriving.
But since they evolved directly from the wild oxen, that extinction wasn’t really a dead end. In the same way, the very first life forms likely went extinct not too long after they appeared, but before they did, a subgroup of the population evolved into a totally new species, which in turn evolved into other species and so on, to form billions of species, many of which are still alive today, all thanks to a long-gone ancestor.
[Jasper] … so… can I tell them where to find the app now?
[Kate] Yeah, this is the ending screen, so… go for it.
[Jasper] Oh! Okay. So… you can find the Evolution Simulator using the link I put in the video description or you can visit minutelabs.io and find a ton of other fun labs to play around with too. I also made a video that goes into some of the inner workings of the evolution simulator over on the MinuteLabs YouTube channel… it’s right over here if you want to watch it. Anything else, Kate?
[Kate] Yes! I want to thank The Great Courses Plus for sponsoring this video; we’re excited to be able to let you all play around with the simulator, and we couldn’t have done it without their support. As you all know by now, The Great Courses Plus is like Netflix for learning, with a library of more than 11,000 lectures. If you’re into evolution, I think you’ll love the course called “Major Transitions In Evolution,” which – over 24 30-minute episodes – takes you on life’s journey from the first life forms all the way through modern humans. Now that’s a binge watch! To get a free trial subscription to The Great Courses Plus and show your support for MinuteEarth, go to TheGreatCoursesPlus.com/minuteearth, or click the link in the description below. Thanks, Great Courses Plus!
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This version removes any informal language and maintains a professional tone while preserving the core content.
Evolution – The process by which different kinds of living organisms develop and change from earlier forms over long periods of time. – Charles Darwin’s theory of evolution explains how species adapt to their environments over generations.
Extinction – The permanent disappearance of a species from the Earth. – The extinction of the dinosaurs occurred approximately 65 million years ago.
Species – A group of similar organisms capable of interbreeding and producing fertile offspring. – The African elephant is a species known for its large ears and tusks.
Environment – The surrounding conditions in which an organism lives, including air, water, and land. – A frog’s environment includes both water and land habitats.
Survival – The ability of an organism to continue living and reproducing in its environment. – Camouflage can increase an animal’s chances of survival by helping it avoid predators.
Competition – The struggle between organisms for the same resources, such as food or territory, in an ecosystem. – In the forest, there is competition among trees for sunlight.
Predation – The interaction where one organism, the predator, hunts and eats another organism, the prey. – Lions rely on predation to catch their prey, such as zebras and antelopes.
Traits – Characteristics or features of an organism that can be inherited or influenced by the environment. – Eye color is one of the many traits that can be passed from parents to offspring.
Genetic – Relating to genes or heredity, which are the instructions in an organism’s DNA that determine traits. – Genetic information is passed from parents to children through DNA.
Mutations – Changes in the DNA sequence of an organism that can lead to new traits or characteristics. – Some mutations can be beneficial and help an organism adapt to its environment.
