Hank gets to the more violent part of community ecology by describing predation and the many ways prey organisms have developed to avoid it.
Hank introduces us to comparative anatomy, which studies the similarities and differences in animal anatomy to support the theory of evolution and the shared ancestry of living things.
Hank continues our exploration of animal phyla with the more complexly organized annelida and arthropoda, and a biolography on insects.
So last episode we talked about some basic file formats, but what we didn’t talk about is compression. Often files are way too large to be easily stored on hard drives or transferred over the Internet - the solution, unsurprisingly, is to make them smaller. Today, we’re going to talk about lossless compression, which will give you the exact same thing when reassembled, as well as lossy compression, which uses the limitations of human perception to remove less important data. From listening to music and sharing photos, to talking on the phone and even streaming this video right now the ways we use the Internet and our computing devices just wouldn’t be possible without the help of compression.
Today we start a three episode arc on the rise of a global telecommunications network that changed the world forever. We’re going to begin with computer networks, and how they grew from small groups of connected computers on LAN networks to eventually larger worldwide networks like the ARPANET and even the Internet we know today. We'll also discuss how many technologies like Ethernet, MAC addresses, IP Addresses, packet switching, network switches, and TCP/IP were implemented to new problems as our computers became ever-increasingly connected. Next week we’ll talk about the Internet, and the week after the World Wide Web!
Today we’re going to talk about how computers see. We’ve long known that our digital cameras and smartphones can take incredibly detailed images, but taking pictures is not quite the same thing. For the past half-century, computer scientists have been working to help our computing devices understand the imagery they capture, leading to advancements everywhere, from tracking hands and whole bodies, biometrics to unlock our phones, and eventually giving autonomous cars the ability to understand their surroundings.
Today we’re going to talk about confidence intervals. Confidence intervals allow us to quantify our uncertainty, by allowing us to define a range of values for our predictions and assigning a likelihood that something falls within that range. And confidence intervals come up a lot like when you get delivery windows for packages, during elections when pollsters cite margin of errors, and we use them instinctively in everyday decisions. But confidence intervals also demonstrate the tradeoff of accuracy for precision - the greater our confidence, usually the less useful our range.
In which John Green teaches you about conflict in Israel and Palestine. This conflict is often cast as a long-term beef going back thousands of years, and rooted in a clash between religions. Well, that's not quite true. What is true is that the conflict is immensely complicated, and just about everyone in the world has an opinion about it. John is going to try to get the facts across in under 13 minutes.
Hank wraps up the Crash Course on ecology by taking a look at the growing fields of conservation biology and restoration ecology, which use all the kung fu moves we've learned about in the past eleven weeks and apply them to protecting ecosystems and to cleaning up the messes that we've already made.
We may be living IN a simulation (according to Elon Musk and many others), but that doesn't mean we don't need to perform simulations ourselves. Today, we're going to talk about good experimental design and how we can create controlled experiments to minimize bias when collecting data. We'll also talk about single and double blind studies, randomized block design, and how placebos work.
This week, Stan Muller teaches you the basics of copyright in the United States. Copyright law is territorial, so we're going to cover the system we know the most about, and that's the US. Stan will talk about what kind of ideas can be copyrighted, who can get a copyright, and what protections the copyright grants. We'll also talk about the always contentious and seemingly ever-growing term of copyright. Stan will also teach you about the low bar for creativity, which means that original work doesn't have to be all that original, and he'll also touch on the problems with copyright in the modern world.
Stan Muller teaches you a few things about copyright enforcement, and talks about the exceptions to copyright enforcement. While there are several, the one you've probably heard of is Fair Use, and it's a pretty tricky one. We'll try to explain it, and teach you just why fair use is so loosey goosey.
Today we’re going to talk about data relationships and what we can learn from them. We’ll focus on correlation, which is a measure of how two variables move together, and we’ll also introduce some useful statistical terms you’ve probably heard of like regression coefficient, correlation coefficient (r), and r^2. But first, we’ll need to introduce a useful way to represent bivariate continuous data - the scatter plot. The scatter plot has been called “the most useful invention in the history of statistical graphics” but that doesn’t necessarily mean it can tell us everything. Just because two data sets move together doesn’t necessarily mean one CAUSES the other. This gives us one of the most important tenets of statistics: correlation does not imply causation.
Starting February 22nd, Carrie Anne Philbin will be hosting Crash Course Computer Science! In this series, we're going to trace the origins of our modern computers, take a closer look at the ideas that gave us our current hardware and software, discuss how and why our smart devices just keep getting smarter, and even look towards the future! Computers fill a crucial role in the function of our society, and it's our hope that over the course of this series you will gain a better understanding of how far computers have taken us and how far they may carry us into the future.
Join Jay Smooth next week for the start of our next miniseries: Crash Course Media Literacy!
Beginning Mondays in March, we are bringing you Crash Course Sociology. Host Nicole Sweeney will walk you through questions big and small about how we both shape societies and are shaped by them. We hope you'll join us.
Welcome to Crash Course Statistics! In this series we're going to take a closer look at how statistics play a significant role in our everyday lives. Now this a "math" course, and there will definitely be some math, but we're going to focus on how statistics is useful and valuable to you - someone that performs AND consumes statistics all the time. Statistics are everywhere from batting averages and insurance rates to weather forecasting and smart assistants, and it's our hope that when you finish this series you'll get a better idea of the role statistics play in helping us better understand the world!
We're back! This year Mike Rugnetta is teaching you about theater and drama. Are you in drama club? Want to know about the history of theater? Maybe learn some theater history? Have a lot of fun? This is the series for you! Over the next year, we're going to learn about the history and workings of the dramatic arts, together. It's going to be a great time, very low drama. Except it's all drama. Embrace the paradox, folks.
We’ve talked about deviance more broadly, but today we’re focusing on crime, specifically in the US. We’ll start with legal definitions of crime and use FBI data to get an idea of the amount and kinds of crime committed in the US. We’ll also use that date to paint a demographic picture of who gets arrested, and explain why that’s not necessarily a full look of who commits crime. We’ll also discuss society’s response to crime in the criminal justice system, and how that response has resulted in mass incarceration.
In which John Green teaches you about the Crusades embarked upon by European Christians in the 12th and 13th centuries. Our traditional perception of the Crusades as European Colonization thinly veiled in religion isn't quite right. John covers the First through the Fourth Crusades, telling you which were successful, which were well-intentioned yet ultimately destructive, and which were just plain crazy. Before you ask, no, he doesn't cover the Children's Crusade, in which children were provoked to gather for a Crusade, and then promptly sold into slavery by the organizers of said Crusade. While this story is charming, it turns out to be complete and utter hooey.