YouTube: | https://youtube.com/watch?v=SyHM1gFyP8Y |
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Comments: | 56 |
Duration: | 12:23 |
Uploaded: | 2024-07-16 |
Last sync: | 2024-08-23 19:30 |
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Citation formatting is not guaranteed to be accurate. | |
MLA Full: | "Biology and You: The Dr. Sammy Show: Crash Course Biology #50." YouTube, uploaded by CrashCourse, 16 July 2024, www.youtube.com/watch?v=SyHM1gFyP8Y. |
MLA Inline: | (CrashCourse, 2024) |
APA Full: | CrashCourse. (2024, July 16). Biology and You: The Dr. Sammy Show: Crash Course Biology #50 [Video]. YouTube. https://youtube.com/watch?v=SyHM1gFyP8Y |
APA Inline: | (CrashCourse, 2024) |
Chicago Full: |
CrashCourse, "Biology and You: The Dr. Sammy Show: Crash Course Biology #50.", July 16, 2024, YouTube, 12:23, https://youtube.com/watch?v=SyHM1gFyP8Y. |
Biology connects all of life—all of YOUR life. In the final episode of Crash Course Biology, Dr. Sammy is taking your questions. No matter how big, small, or personal, biology is in them all! He’ll show us how biology can help us solve problems and understand everyday life.
Introduction: Biology and You 00:00
Stress Response 01:27
Ecological Niches 3:15
Water Solvency 4:34
Unity of Life 6:16
Biology as a Career 7:50
Evolution 9:13
Final Review & Credits 10:47
This series was produced in collaboration with HHMI BioInteractive, committed to empowering educators and inspiring students with engaging, accessible, and quality classroom resources. Visit https://BioInteractive.org/CrashCourse for more information.
Check out our Biology playlist here: https://www.youtube.com/playlist?list=PL8dPuuaLjXtPW_ofbxdHNciuLoTRLPMgB
Watch this series in Spanish on our Crash Course en Español channel here: https://www.youtube.com/playlist?list=PLkcbA0DkuFjWQZzjwF6w_gUrE_5_d3vd3
Sources: https://docs.google.com/document/d/1GLDtAXE6ekg4Chk2qN3TYbNt0pJbyaHqTqRd6QY8pd4/edit?usp=sharing
***
Support us for $5/month on Patreon to keep Crash Course free for everyone forever! https://www.patreon.com/crashcourse
Or support us directly: https://complexly.com/support
Join our Crash Course email list to get the latest news and highlights: https://mailchi.mp/crashcourse/email
Get our special Crash Course Educators newsletter: http://eepurl.com/iBgMhY
Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
Forrest Langseth, Emily Beazley, Neeloy Gomes, oranjeez, Rie Ohta, Jack Hart, UwU, Leah H., David Fanska, Andrew Woods, Stephen Akuffo, Ken Davidian, Toni Miles, AmyL, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Krystle Young, Burt Humburg, Perry Joyce, Scott Harrison, Alan Bridgeman, Mark & Susan Billian, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, Bernardo Garza, team dorsey, Trevin Beattie, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Barrett Nuzum, Nathan Taylor, Les Aker, William McGraw, Rizwan Kassim, Vaso , ClareG, Alex Hackman, Constance Urist, kelsey warren, Katie Dean, Stephen McCandless, Wai Jack Sin, Ian Dundore, Caleb Weeks
__
Want to find Crash Course elsewhere on the internet?
Instagram - https://www.instagram.com/thecrashcourse/
Facebook - http://www.facebook.com/YouTubeCrashCourse
Twitter - http://www.twitter.com/TheCrashCourse
CC Kids: http://www.youtube.com/crashcoursekids
Introduction: Biology and You 00:00
Stress Response 01:27
Ecological Niches 3:15
Water Solvency 4:34
Unity of Life 6:16
Biology as a Career 7:50
Evolution 9:13
Final Review & Credits 10:47
This series was produced in collaboration with HHMI BioInteractive, committed to empowering educators and inspiring students with engaging, accessible, and quality classroom resources. Visit https://BioInteractive.org/CrashCourse for more information.
Check out our Biology playlist here: https://www.youtube.com/playlist?list=PL8dPuuaLjXtPW_ofbxdHNciuLoTRLPMgB
Watch this series in Spanish on our Crash Course en Español channel here: https://www.youtube.com/playlist?list=PLkcbA0DkuFjWQZzjwF6w_gUrE_5_d3vd3
Sources: https://docs.google.com/document/d/1GLDtAXE6ekg4Chk2qN3TYbNt0pJbyaHqTqRd6QY8pd4/edit?usp=sharing
***
Support us for $5/month on Patreon to keep Crash Course free for everyone forever! https://www.patreon.com/crashcourse
Or support us directly: https://complexly.com/support
Join our Crash Course email list to get the latest news and highlights: https://mailchi.mp/crashcourse/email
Get our special Crash Course Educators newsletter: http://eepurl.com/iBgMhY
Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
Forrest Langseth, Emily Beazley, Neeloy Gomes, oranjeez, Rie Ohta, Jack Hart, UwU, Leah H., David Fanska, Andrew Woods, Stephen Akuffo, Ken Davidian, Toni Miles, AmyL, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Krystle Young, Burt Humburg, Perry Joyce, Scott Harrison, Alan Bridgeman, Mark & Susan Billian, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, Bernardo Garza, team dorsey, Trevin Beattie, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Barrett Nuzum, Nathan Taylor, Les Aker, William McGraw, Rizwan Kassim, Vaso , ClareG, Alex Hackman, Constance Urist, kelsey warren, Katie Dean, Stephen McCandless, Wai Jack Sin, Ian Dundore, Caleb Weeks
__
Want to find Crash Course elsewhere on the internet?
Instagram - https://www.instagram.com/thecrashcourse/
Facebook - http://www.facebook.com/YouTubeCrashCourse
Twitter - http://www.twitter.com/TheCrashCourse
CC Kids: http://www.youtube.com/crashcoursekids
**Telephone ring** **Telephone ring** **Telephone ring** Crash Course Biology hotline.
Dr. Sammy, your friendly neighborhood entomologist speaking.
How may I help you? [Student Sammy] Hi Dr. Sammy, long-time viewer, first-time caller. I’m so stressed out.
I have a test after lunch, a flute recital tonight, an essay due tomorrow, my crush left me on read 3 days ago. And I'm losing my tater tots. Like literally!
Like I don’t even know where they're going... How do I keep it together? [Dr. Sammy] I'm so glad you called.
Would you believe that I'm not most people's first choice for life advice? I know! I'm a biologist — life is literally my specialty.
And biology is everywhere. We've found it in cancer cells and chemical reactions, evolution, and elephants. But the science of life is also in your everyday life.
And believe it or not, there is a bit of biology at work here in your tater tot tumult. Actually, quite a bit. So yeah, I will answer this question, and ALL your questions to show you how your life brings together biological principles from the tiny to the tremendous.
Prepare to be amazed… as soon as I find my theme music. We’re gonna have to tie a bell around that thing; I feel like I lose it every week! [THEME MUSIC] Man, I’m gonna miss that theme music. Okay, back to your question.
I know it feels like you don’t have it together, but rest assured: your body does. Through constant tweaking, your molecular machinery strives for homeostasis: a steady state that allows life to keep living, whatever it’s facing. I mean not whatever you’re facing, if it’s a flamethrower, you’re probably toast… Your body has been shaped by millions of years of evolution to respond to any and all challenges to that stability.
So, that stressed-out, can’t even-hold-onto-your-tots feeling is actually a sign that everything’s working properly as your body manages stress with a rush of chemical messengers: hormones. Your brain, sensing a threat, is revving your body up to do something about it. A surge of hormones triggers your heart to beat faster and your breath to quicken – pumping more blood and oxygen through your body to your vital organs to help you run away from a lion, or, in your case, think more quickly for a test.
As long as they don’t overdo it making you too jittery to get those thoughts out clearly. And a stress response is a good thing — as long as it turns off when it’s not needed. A body stuck in stress mode is more likely to get sick.
You can help your body turn off stress mode by getting enough sleep, exercise, time with supportive friends, and of course, by remembering to study well in advance of your exam rather than cramming the night before. For now: breathe. Deep belly breaths interrupt the stress response and relax your muscles.
Seriously, breathe: you’ve got this, tots or no tots. [Pajama Sammy] Dr. Samuel. I love cheesy popcorn, but my dog keeps eating it!
And I get her her own popcorn-flavored treats, but she just keeps eating mine. What am I supposed to do ? [Dr. Sammy] Well, you could send your pup on over to my place.
My jokes are extra cheesy so she can munch on those to her heart’s content. But, seriously, we’re connected to other living things — from our food systems to our energy sources. So thinking ecologically here might solve your popcorn problem.
You and your dog are two organisms in the same food web, jostling for the same popcorn niche, like two anole lizards living in the same tree, snacking on the same crickets. When two organisms are competing neither gets as many resources as it would without competition so even the winner loses a little. That’s a life lesson right there.
So, how do you prevent that popcorn-poaching? Do as the anoles do! Different anole species manage to live in harmony by snacking in different parts of the tree.
Canopy for one, trunk for the other. So, split your niche! Your dog is probably going to keep plundering your popcorn if you leave it where she can reach it, but if you put it up on the top shelf, well, chances are she isn’t going to get a ladder and go looking for it.
Though if that does happen, could you call a brutha back because I’m definitely gonna need to study this behavior. [Spaghetti Sammy] Hey, uh, hey doc, I got a bit of a situation here, a little… spaghetti sauce…on my favorite shirt. And I just don’t know how to get it out. And we’re kinda in a time-sensitive situation here if you catch my drift. [Dr.
Sammy] That sounds…concerning. Uhhhhh… well, I’m gonna assume this is a food-based stain, so to get that Ragu rag-gone, you’re gonna wanna grab one of the most amazing molecules around: water. It supports life and busts stains through its power of dissolving some things but not others.
It’s not just a solvent, it’s The Solvent. Now, you’re also gonna call upon the awesome power of enzymes: proteins that speed up chemical reactions. Enzymes are in all living things, you included.
They’re part of how the molecules composing spaghetti that actually make it into your mouth get broken up into usable energy. And thanks to biological knowledge, we’re able to harvest enzymes from microbes grown in laboratories (like the tiniest livestock ever) and put their power in detergents! Thanks little guys!
Anyway, here’s what you’re gonna do: add some water to the stain. Then scrub in some enzymatic detergent, can’t provide you any brand names; Crash Course prides itself on being detergent impartial. But, you’ll want one that has enzymes specially suited to certain molecules, like lipases that break apart fats and amylases that break down starches.
And that’s most of what spaghetti is. Then other detergent molecules with water-loving heads and water-repelling tails will lift those bits up and off the fabric. Where the water will dissolve them and wash them away.
Pasta La Vista, baby. [Rocky’s Mom] Dr. Sammy, I love Rocky. But, he’s just not bringing a lot of engagement in my life right now.
Should I get maybe a tarantula, a goldfish, or a coconut crab as my first pet? I just think Rocky really needs a friend. Thank you for taking my call. [Dr.
Sammy] A predator no heavier than a grapefruit, a fish that can live over a decade, or a top contender for the most beautiful species on Earth? Not that I'm biased or anything. Because really, all of those options have a lot in common not only with each other but also… with you.
Like, you’re all quite literally made of the same stuff: biological molecules formed billions of years ago. We living things just sort of pass this stuff around the food chain, and despite our different bodies, we use many of the same chemical reactions to harness energy. On top of that, you and all your prospective pets have traits that were passed down by evolutionary forces that helped you survive.
Like, that’s why both you and your hypothetical tarantula have hair, though it evolved independently in each of you. And sadly, unlike the tarantula, you can’t torpedo your hair at stuff that scares you. Missed opportunity evolution.
But the things we don't have in common... matter a lot. Unlike you, the goldfish needs water to breathe. And that coconut crab — well, it’s gonna take up a lot more room than either of them, which means it’ll need more calories.
It’s not easy maintaining such dramatic awesomeness. All that said, since this is your first pet, caller, I’d recommend sticking with something more low maintenance – like a hissing cockroach or maybe a giant African millipede... Yeah...
Yeah.. [Cool Sammy] Aye yooooo Dr. Sammy you answered, Good look bruh. Aye uuuh for real for real, I’ve got no idea what I want to be when I grow up.
I know I love fashion. But like biology is cool, too. You feel me?
Like, what should I do bruh? [Dr. Sammy] What to do with a life? You've provided a question that the science of life can’t answer.
But, biology will be in the answer no matter what. Take your interest in fashion, for starters. Cotton fabrics have been around for at least 5,000 years because humans selectively bred wild plants for extra fluff.
Some clothes are even made with red pigment called cochineal produced by insects. And fashion and biology are still meeting up today! Like, there are these copper-infused textiles that kill off, fungi, viruses, and other microbes.
Who knows, maybe you’ll design the world’s an antimicrobial swimsuit. And biological knowledge could take you down a bunch of other fascinating paths. You could develop new medicines, cosmetics, or compostable plastics.
You could train athletes, treat diseases, or breed crops that resist pests and tolerate droughts. You could write about biology for the public, teach it in a high school, or be a naturalist at a state park. You could be a civil engineer, picking plants for cities to support native wildlife and connect fragmented ecosystems.
Or maybe you’d enjoy being a research scientist, asking super-specific questions about whale songs, liver cells…or honey bees, like me. [High School Sammy] So, I’m going to college next year, and I want to be a whole new me when I get there. How do I have, like, a personal evolution? Would a new hat help? [Dr.
Sammy] Oh caller. Caller, caller, caller. A new hat is always a gamble.
I barely made it out of my last bucket hat era. But anyway, caller, I’ll start with the bad news. As an individual organism, you can’t evolve.
Not biologically, anyway. Evolution only happens in populations over many generations, as some individuals pass on their genes and others don’t. So there are limits here.
You can try a new hairstyle. But you can’t evolve longer leg bones or X-ray vision. That doesn’t mean you can’t change, though.
What it seems you’re thinking of is a metamorphosis and that kind of change can happen to a creature during its lifetime like with tadpoles or caterpillars. We use the term a bit more loosely with humans though. In fact, you’re changing right now.
Many of your cells—trillions of tiny lives inside you that together are you—are constantly getting replaced. How’s that for a Ship of Theseus problem? On top of that, you’ve inherited a particular mix of genes that, for the most part, can’t change.
But their expression as actual traits can. Expression is shaped by your ongoing experiences, which can change you — throughout your lifetime. So you can’t evolve biologically speaking, but you’re always changing.
You’re still part of evolution’s long story. And I find some comfort in that. We’re all here because our ancestors made it.
And you know what? A new hat is always a risk. But if your ancestors could make it through everything it took for you to be here, why not go for it.
And might I recommend a fedora? It’s a great conversation starter. Whether you just joined today or you’ve been with us for all fifty episodes, there’s one idea we want to leave you with: connection.
All the layers of life we’ve talked about — cells, genes, anatomy, ecology — are constantly interacting, shaping the world that you experience. They link you not only to all of life…but to the universe itself. Nearly every element in your body traces back to explosions from long-ago stars, scattered and looped into cycles far older than our species’ memory.
You’re made of borrowed stardust, just passing through. But you ignite this cosmic arrangement with a life that’s entirely yours. Wherever life takes you, the science of life will be there—helping us understand ourselves and the big, boisterous, four billion-year-old family we’re all a part of.
So from me, Patty, and all 8,351 members of the Yeasty family…thanks for watching. This series was produced in collaboration with HHMI BioInteractive. If you’re an educator, visit BioInteractive.org/CrashCourse for classroom resources and professional development related to the topics covered in this course.
Thanks for watching this episode of Crash Course Biology, which was filmed at our studio in Indianapolis, Indiana, and was made with the help of all these nice people. If you want to help keep Crash Course free for everyone, forever, you can join our community on Patreon.
Dr. Sammy, your friendly neighborhood entomologist speaking.
How may I help you? [Student Sammy] Hi Dr. Sammy, long-time viewer, first-time caller. I’m so stressed out.
I have a test after lunch, a flute recital tonight, an essay due tomorrow, my crush left me on read 3 days ago. And I'm losing my tater tots. Like literally!
Like I don’t even know where they're going... How do I keep it together? [Dr. Sammy] I'm so glad you called.
Would you believe that I'm not most people's first choice for life advice? I know! I'm a biologist — life is literally my specialty.
And biology is everywhere. We've found it in cancer cells and chemical reactions, evolution, and elephants. But the science of life is also in your everyday life.
And believe it or not, there is a bit of biology at work here in your tater tot tumult. Actually, quite a bit. So yeah, I will answer this question, and ALL your questions to show you how your life brings together biological principles from the tiny to the tremendous.
Prepare to be amazed… as soon as I find my theme music. We’re gonna have to tie a bell around that thing; I feel like I lose it every week! [THEME MUSIC] Man, I’m gonna miss that theme music. Okay, back to your question.
I know it feels like you don’t have it together, but rest assured: your body does. Through constant tweaking, your molecular machinery strives for homeostasis: a steady state that allows life to keep living, whatever it’s facing. I mean not whatever you’re facing, if it’s a flamethrower, you’re probably toast… Your body has been shaped by millions of years of evolution to respond to any and all challenges to that stability.
So, that stressed-out, can’t even-hold-onto-your-tots feeling is actually a sign that everything’s working properly as your body manages stress with a rush of chemical messengers: hormones. Your brain, sensing a threat, is revving your body up to do something about it. A surge of hormones triggers your heart to beat faster and your breath to quicken – pumping more blood and oxygen through your body to your vital organs to help you run away from a lion, or, in your case, think more quickly for a test.
As long as they don’t overdo it making you too jittery to get those thoughts out clearly. And a stress response is a good thing — as long as it turns off when it’s not needed. A body stuck in stress mode is more likely to get sick.
You can help your body turn off stress mode by getting enough sleep, exercise, time with supportive friends, and of course, by remembering to study well in advance of your exam rather than cramming the night before. For now: breathe. Deep belly breaths interrupt the stress response and relax your muscles.
Seriously, breathe: you’ve got this, tots or no tots. [Pajama Sammy] Dr. Samuel. I love cheesy popcorn, but my dog keeps eating it!
And I get her her own popcorn-flavored treats, but she just keeps eating mine. What am I supposed to do ? [Dr. Sammy] Well, you could send your pup on over to my place.
My jokes are extra cheesy so she can munch on those to her heart’s content. But, seriously, we’re connected to other living things — from our food systems to our energy sources. So thinking ecologically here might solve your popcorn problem.
You and your dog are two organisms in the same food web, jostling for the same popcorn niche, like two anole lizards living in the same tree, snacking on the same crickets. When two organisms are competing neither gets as many resources as it would without competition so even the winner loses a little. That’s a life lesson right there.
So, how do you prevent that popcorn-poaching? Do as the anoles do! Different anole species manage to live in harmony by snacking in different parts of the tree.
Canopy for one, trunk for the other. So, split your niche! Your dog is probably going to keep plundering your popcorn if you leave it where she can reach it, but if you put it up on the top shelf, well, chances are she isn’t going to get a ladder and go looking for it.
Though if that does happen, could you call a brutha back because I’m definitely gonna need to study this behavior. [Spaghetti Sammy] Hey, uh, hey doc, I got a bit of a situation here, a little… spaghetti sauce…on my favorite shirt. And I just don’t know how to get it out. And we’re kinda in a time-sensitive situation here if you catch my drift. [Dr.
Sammy] That sounds…concerning. Uhhhhh… well, I’m gonna assume this is a food-based stain, so to get that Ragu rag-gone, you’re gonna wanna grab one of the most amazing molecules around: water. It supports life and busts stains through its power of dissolving some things but not others.
It’s not just a solvent, it’s The Solvent. Now, you’re also gonna call upon the awesome power of enzymes: proteins that speed up chemical reactions. Enzymes are in all living things, you included.
They’re part of how the molecules composing spaghetti that actually make it into your mouth get broken up into usable energy. And thanks to biological knowledge, we’re able to harvest enzymes from microbes grown in laboratories (like the tiniest livestock ever) and put their power in detergents! Thanks little guys!
Anyway, here’s what you’re gonna do: add some water to the stain. Then scrub in some enzymatic detergent, can’t provide you any brand names; Crash Course prides itself on being detergent impartial. But, you’ll want one that has enzymes specially suited to certain molecules, like lipases that break apart fats and amylases that break down starches.
And that’s most of what spaghetti is. Then other detergent molecules with water-loving heads and water-repelling tails will lift those bits up and off the fabric. Where the water will dissolve them and wash them away.
Pasta La Vista, baby. [Rocky’s Mom] Dr. Sammy, I love Rocky. But, he’s just not bringing a lot of engagement in my life right now.
Should I get maybe a tarantula, a goldfish, or a coconut crab as my first pet? I just think Rocky really needs a friend. Thank you for taking my call. [Dr.
Sammy] A predator no heavier than a grapefruit, a fish that can live over a decade, or a top contender for the most beautiful species on Earth? Not that I'm biased or anything. Because really, all of those options have a lot in common not only with each other but also… with you.
Like, you’re all quite literally made of the same stuff: biological molecules formed billions of years ago. We living things just sort of pass this stuff around the food chain, and despite our different bodies, we use many of the same chemical reactions to harness energy. On top of that, you and all your prospective pets have traits that were passed down by evolutionary forces that helped you survive.
Like, that’s why both you and your hypothetical tarantula have hair, though it evolved independently in each of you. And sadly, unlike the tarantula, you can’t torpedo your hair at stuff that scares you. Missed opportunity evolution.
But the things we don't have in common... matter a lot. Unlike you, the goldfish needs water to breathe. And that coconut crab — well, it’s gonna take up a lot more room than either of them, which means it’ll need more calories.
It’s not easy maintaining such dramatic awesomeness. All that said, since this is your first pet, caller, I’d recommend sticking with something more low maintenance – like a hissing cockroach or maybe a giant African millipede... Yeah...
Yeah.. [Cool Sammy] Aye yooooo Dr. Sammy you answered, Good look bruh. Aye uuuh for real for real, I’ve got no idea what I want to be when I grow up.
I know I love fashion. But like biology is cool, too. You feel me?
Like, what should I do bruh? [Dr. Sammy] What to do with a life? You've provided a question that the science of life can’t answer.
But, biology will be in the answer no matter what. Take your interest in fashion, for starters. Cotton fabrics have been around for at least 5,000 years because humans selectively bred wild plants for extra fluff.
Some clothes are even made with red pigment called cochineal produced by insects. And fashion and biology are still meeting up today! Like, there are these copper-infused textiles that kill off, fungi, viruses, and other microbes.
Who knows, maybe you’ll design the world’s an antimicrobial swimsuit. And biological knowledge could take you down a bunch of other fascinating paths. You could develop new medicines, cosmetics, or compostable plastics.
You could train athletes, treat diseases, or breed crops that resist pests and tolerate droughts. You could write about biology for the public, teach it in a high school, or be a naturalist at a state park. You could be a civil engineer, picking plants for cities to support native wildlife and connect fragmented ecosystems.
Or maybe you’d enjoy being a research scientist, asking super-specific questions about whale songs, liver cells…or honey bees, like me. [High School Sammy] So, I’m going to college next year, and I want to be a whole new me when I get there. How do I have, like, a personal evolution? Would a new hat help? [Dr.
Sammy] Oh caller. Caller, caller, caller. A new hat is always a gamble.
I barely made it out of my last bucket hat era. But anyway, caller, I’ll start with the bad news. As an individual organism, you can’t evolve.
Not biologically, anyway. Evolution only happens in populations over many generations, as some individuals pass on their genes and others don’t. So there are limits here.
You can try a new hairstyle. But you can’t evolve longer leg bones or X-ray vision. That doesn’t mean you can’t change, though.
What it seems you’re thinking of is a metamorphosis and that kind of change can happen to a creature during its lifetime like with tadpoles or caterpillars. We use the term a bit more loosely with humans though. In fact, you’re changing right now.
Many of your cells—trillions of tiny lives inside you that together are you—are constantly getting replaced. How’s that for a Ship of Theseus problem? On top of that, you’ve inherited a particular mix of genes that, for the most part, can’t change.
But their expression as actual traits can. Expression is shaped by your ongoing experiences, which can change you — throughout your lifetime. So you can’t evolve biologically speaking, but you’re always changing.
You’re still part of evolution’s long story. And I find some comfort in that. We’re all here because our ancestors made it.
And you know what? A new hat is always a risk. But if your ancestors could make it through everything it took for you to be here, why not go for it.
And might I recommend a fedora? It’s a great conversation starter. Whether you just joined today or you’ve been with us for all fifty episodes, there’s one idea we want to leave you with: connection.
All the layers of life we’ve talked about — cells, genes, anatomy, ecology — are constantly interacting, shaping the world that you experience. They link you not only to all of life…but to the universe itself. Nearly every element in your body traces back to explosions from long-ago stars, scattered and looped into cycles far older than our species’ memory.
You’re made of borrowed stardust, just passing through. But you ignite this cosmic arrangement with a life that’s entirely yours. Wherever life takes you, the science of life will be there—helping us understand ourselves and the big, boisterous, four billion-year-old family we’re all a part of.
So from me, Patty, and all 8,351 members of the Yeasty family…thanks for watching. This series was produced in collaboration with HHMI BioInteractive. If you’re an educator, visit BioInteractive.org/CrashCourse for classroom resources and professional development related to the topics covered in this course.
Thanks for watching this episode of Crash Course Biology, which was filmed at our studio in Indianapolis, Indiana, and was made with the help of all these nice people. If you want to help keep Crash Course free for everyone, forever, you can join our community on Patreon.