Simulating Natural Selection

A few places to learn more about evolution and natural selection:
Any intro biology text you might have access to.

Special thanks to supporters on Patreon, especially:
Jordan Scales
Eric Helps
Ben Kamens
Ben Komalo
Christy Serbus
Sean Barker

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For discussion and updates
- Reddit: r/primerlearning
- Twitter: @primerlearning

Streaming myself working on these monstrosities:

This video is presented under a Creative Commons Attribution-NonCommercial-ShareAlike License. More at:

Made with Blender and python.

[PrimerBlobs]

If you're about to leave a comment saying that faster creatures aren't actually less efficient, read this first. I presented that part a bit strangely.

At 2:14, I say moving quickly is less efficient, giving the example of a creature moving a unit distance in half the time, using twice the energy. Then, at 4:53, I show a formula for the energy cost per unit time, which depends on the square of the creature's speed.

I gave distance per time, energy per time, and distance per energy at separate parts of the video, and that was confusing.

So here's a more explicit summary.
If we double a creature's speed...
- its distance per time is doubled (the definition of speed)
- its energy per time is quadrupled (because it depends on the square of speed)
- its distance per energy is halved: (2x distance per time) / (4x energy per unit time)

That last bullet is the "efficiency" from the video. With its starting energy for a day, a 2x-speed creature can only travel half the distance.

[tamircohen]

This video drastically exceeded my expectations. This is one of the highest quality, most informative and engaging videos I've seen in a long while. You have earned my like and subscription! Looking forward to seeing more of your videos.

[theCodyReeder]

Well I'm just going to click that little red rectangular button and hope it shows me more like this.

[noctobyte]

Man cut the food to a tenth, started a mass famine and said ‘Hm’ when they all died lmao

[tomkt]

"We're living in a simulation!" - The Blobs probably

[ddpnh]

I'm glad the YouTube algorithm is evolving and finally recommended me something good.

[antoineringuette]

"The other day I came across somebody that more than 20% larger than me. It's a good thing I had better sense and better speed. That was scary. I guess I'm truly living on the edge!"

- Blob

[KarakovAnuar]

I bet those blobs are like
-dude, what's the meaning of life
-I think we live in a simulation
-what a stupid theory

[alexpartain]

In all seriousness, this should be shown in classrooms. It really does explain topics very very well providing a visual and being able to see it really helps rather than just reading it.

[ironwoodkid]

TFW youtube recommends something interesting for a change

[deliciousserotonin]

we now know the secret to immortality: just eat food every day

[drycleanonly]

I just watched a video about little avocado people and natural selection. No regrets.

Edit: Thanks for the likes boys

[davidsc]

I'm a biologist and researcher in cell biology. I just discovered this channel and I have to say it is possibly the best way out there to quickly learn and understand how evolution works. Amazing modeling. Thanks!

[drekaflugan]

Just remember kids, simulations are just a fragment of the complexity of reality, there are so many other variables to take into consideration, that it's hard to simulate them all. For example, I am small but I have an easy time eating larger people :)

[TransitNerd]

Can we have a moment of silence for the blobs that never made it back home?

[Santuaa]

"Let's see what happens when we change the environment more explicitly. Let's go to ten food each day." -J. V. Stalin, 1932

[Elidhion]

I'm an Evolutionary Biologist and man this is great popularization of science. Keep up the good work

[mh]

Very nice simulation. A fine example of "Survival of the Fittest". People always get that wrong. "Fittest" is not strongest or fastest, it's 'that which fits best' in its environment.

[MrKalerender]

I'm so glad I rewatched this and discovered there's a simulation for students to involve themselves with now. I plan on having my class use this to more thoroughly explore natural selection next year!

[jd-hslj]

“Which you might notice is similar to the formula for kinetic energy.” Funnily enough that wasn’t my first thought!