I can't believe biology did not emerge as a formal discipline until 1859. I would have thought it would have been older. Goes to show how new modern science and our modern world are in the greater scheme of human history and natural history.

Stop reading the comments you have a test on Monday.

Those two giants of biology deserve all the credit they can get. To come up with a mechanism for evolution is no small feat. And to travel around the world on a ship in the 19th century is not pleasant. I'm still in awe of their deep understanding even by today's standards.

This video is awesome! After being a biology teacher for 15 years, I wish I would’ve had this summary long ago. Fantastic job! Simplified, clear, entertaining, accurate, historically synthesized and relevant, beautiful job. Donation and support here I come!!

I remembered back in uni our lecturer asked us to see an exhibition about Wallace. Here in Singapore we still have his samples and remember him. He has a cabinet display at Lee Kong Chian Natural History Museum and also a learning centre named after him, Wallace Education Centre at Dairy Farm Nature Park

Why does it make me giggle every time Hank refers to Charles Darwin as "Chuck"?

Is it just me or should Crash Course make children books (or just illustrated books in general) about their different videos and topics?

you guys have really done a bang up job with this series

The thing that social darwinists don’t understand is that the trait that has made humans successful is our capacity for cooperation.

This is amazing! Intelligent, informative and humorous. Thank you!

Wallace was a brilliant scientist with an amazing life story. Thanks for shedding some light on him. Great intro to Darwin as well!

What an amazing set of discoveries we learned from Charles Darwin!

Wallace deserves far more recognition than what he gets.

its gonna be a really good episode, i really sense the excitement in your eyes Hank !

Thank you Hank, John, and everyone. I've watched hundreds of hours and I owe you so much. Not ready yet, but my patreon membership is imminent..

Fun fact: Charles Darwin was born on the exact same day as Abraham Lincoln.

This is the best history of science episode so far.

Evolution the process by which life changes over time, and in order to function it requires two things. The first is mutation-- random alterations in the genetic material over time due to copying errors, and the second is natural selection-- a non-random process that drives how mutations are spread through a given environment. Mutations are extremely well documented and are actually the source of some of the more deadly diseases to afflict animals across the planet. There are two major types of mutations that can occur. The first is a point mutation. A point mutation occurs when a base in a gene is swapped for another base, and nothing has been inserted or removed. The result is generally benign or produces no effect in the resulting protein as the amino acid is not altered (There are 64 possible combinations in a single codon, which consists of 3 base-pairs, and there are only 20 amino acids used in life on earth. As a result, more than one codon can code for the same amino acid). For example, sickle-cell anemia is a point mutation that produces malformed hemoglobin and increases the risk of various cardiovascular complications (due to their rigid shape). The second type of mutation involves the insertion and removal of nucleotides from the gene and is prone to causing problems in translation. This sort of mutation causes problems because a single codon consists of 3 base pairs, and has designated start and stop signatures that are read by tRNA. When a single nucleotide is inserted into a sequence it can cause the translation of this gene into a protein to start or stop prematurely-- this is known as a frame-shift, and if this happens the mutation is referred to as a frame-shift mutation. Of course, these sorts of mutations can occur with more than one nucleotide at a time, as is the case with Tay-Sachs disease. Tay-Sachs is most frequently caused by the insertion of four nucleotides into the HEXA (hexosaminidase A) gene, and the result is progressive deterioration of nerve cells-- generally starting at around six months old. There are several other kinds of mutations that can occur, though this should do for the basics. On to natural selection... Natural selection is an observable process that has to do with a given population of animals. Specifically, it's a combination of social and ecological pressures on a population that causes mutations to propagate in a non-random pattern. Animals that express mutations that are ill-suited to their environments are less likely to pass on those genes when compared to animals that express genes that allow them to thrive more adequately given current pressures. This means that if you have a mutation that causes a disease such as sickle-cell anemia, you're (slightly) less likely to pass on that trait unless you live in an area of the world that is afflicted by Malaria, to which sickle-cell anemia provides natural resistance. As a result, sickle-cell anemia is quite common in tropical and sub-tropical regions of the world and still lingers in the populations of people who hail from these regions. So to summarize: - Mutations occur at random. - Mutations come in several varieties, the most important for our purposes right now are insertion, deletion, frame-shift, and point. - Point mutations are less likely to lead to health problems than insertion or deletion mutations because more than one codon can code for the same amino acid. - A frame-shift can cause tRNA to begin or end translation from RNA to a protein prematurely and will cause the sequence following the frame-shift mutation to translate incorrectly. - Natural selection is NOT random and is the result of environmental pressures on a population. And from this we can make the following rather basic logical deductions: - It is more likely for a point mutation to propagate through an environment than a mutation that adds or removes nucleotides. - Insertion and deletion mutations are more likely to propagate through a population if they insert or remove nucleotides in multiples of three. - A mutation does NOT need to be entirely beneficial to propagate. The benefits need only outweigh the detriments in a given environment. (See also: sickle-cell anemia) - Animals better suited to their environment are more likely to thrive in it than animals that are not. Pretty simple, right? Here's the tricky part. Because genes are passed down from parent(s) to child(ren), you have an accumulation of mutations over time. Because mutations occur at random during the copying process, any part of your genome can be affected by them. Since both of these things are true, then that means that mutations can be accumulated by a population over time. If mutations can be accumulated by a population over time, there will come a time where a species will no longer share enough DNA in common with its ancestors to breed successfully (children will be sterile, stillborn, will miscarriage, or won't even fertilize an egg). This is what is known as speciation. This, in a nutshell, is evolution.

For a good in-depth textbook overview of the history of evolutionary theory-including the preliminaries to Darwin's theory, as discussed in previous episodes-I highly recommend "Evolution: The History of an Idea" by Peter J. Bowler, a distinguished historian of science and professor at Queen's University Belfast.

wow I literally just searched for this exact video an hour ago as I'm cramming for my anthropology test. And then you just upload it in front of my very eyes :o

I'm just so happy this series exists.

I love the ongoing in-joke about Darwin and Wallace in the movie "The Fall". A fictional version of a young Charles Darwin is shown wearing a psychedelic, butterfly patterned coat. His secret companion is a monkey named Wallace that he keeps hidden in a sack. He's able to understand Wallace who repeatedly chatters helpful ideas pertinent to the bizzare situations in which they end up. Ideas that Darwin repeatedly passes off as his own.

Can't wait for the next episode!

I have long awaited this day!!!

Darwin and Natural Selection talking about Wallace I greatly appreciate, and great for him to get a shout out as the creator of Biogeography, but can we get a series focusing on "Great People of Science" (and other disciplines) where we get an episode or two focusing exclusively on individuals such as Darwin and Wallace?

Actually, this video about Charles Darwin, Alfred Russel, Wallance with their natural selection is something familiar to me. I think when I was in grade 9 or 10. Darwin Wallance as the one man who truly understand the idea of evolution by natural selection. Natural selection can be used by farmers to generate organisms with desirable fruits. Darwin Theory explained through the natural selection, more individuals are produced each generation than can survive. I'm amazed to the both of them! Thanks to this video.

Such an interesting episode!

This will help me on my assignment thank you. :D

Anyone else here during quarantine for Bio Class?

I love the remake of the intro theme.

Awesome episode

Fun fact: the only thing Darwin's theory of evolution was missing at the time was an article written by Mendel. His article was one of very few Darwin probably never read as he didn't take any notes on a copy he had.

Perfect timing seeing as I have a midterm on this exact subject tomorrow

Nicely Done 👌🏾

Ahh man I just summarized an entire chapter on Darwin when I could have just watched this

As someone who just finished reading On the Origin of Species, I'm so glad you focused on the other creatures he studied so I could learn WHY HE WOULDN'T STOP TALKING ABOUT PIGEONS. (Also he literally only mentions finches twice)

Thanks really wanted to learn about this

On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life *

Watching this for my History 04B class!!

Very informative video 👍

I love how they make it interesting!

It's often difficult to find one's self in the Context of The evolution of the Genome . Yet , there you are

Thank you for this

Love you guys.❤

Love this video

This is good art direction.

Cool video!

WELL STATED! Thx!

Darwin, the scientist that was known to eat his specimens That was why it was so hard to get a Galapagos tortoise to zoos at the time. They were apparently quite tasty and never survived the trip.

Thankyou, this was really helpful for my project about Charles Darwin.

ME: this video could help me A's my exam FUTURE ME: nah a got a normal sore -_-

I love this episode...

Hank: there are no stupid, ugly turtles me: there's one. Mitch McConnell

Great video, thank you very much , note to self(nts) watched all of it 12:28

Yo that background for the credits tho 😍 need google image sesrch

i STAN hank

I've been waiting for this one Love the channels

If you get the chance, watch the 1978 BBC mini-series, The Voyage of Charles Darwin

The fundamental idea of Social Darwinism, that some classes and/or races of people are fundamentally and inherently inferior to others and it is therefore counterproductive to society to spend resources on them, predates Darwin by more than 100 years. As you point out, it was these economic theories that influenced Darwin and Wallace. And in a kind of feedback-loop, some of Darwin's most enthusiastic supporters were the economists who were pushing this idea. In Natural Selection, they recognized a scientific theory they could dress their prejudice up in. And the echoes of those socioeconomic theories can still be heard in the politics and policies of the modern world.

Malthusianism is a useful primitive model for animal populations, but it's worth noting that its application to humans was refuted in 1879 by Henry George.

Very nicely explained. well, Why these theory are not talk much about plants and vegetation,

Where are my science majors at?!

Wow, hank is back

Q: Why did the creatard ask a snake to help him with his illness instead of a doctor? A: Creatards believe in talking snakes but not antibiotics

This is the best evolution i ever seen in the earth b

1:42 1 of many reasons why i love crash course

im actually related to darwins wife and that side of the family

By "fittest" does it mean those that fit the environment the best?

Every time I watch this video, I can't help but imagine just how brilliant Darwin and Wallace were. Discovering natural selection was no mean feat.

I just started rereading Kurt Vonnegut's novel Galapagos. Casual serendipity or formal synchronicity? 😉

Galileo was born the same year Michelangelo died. Newton was born the same year Galileo died.

IT'S COMING! EVERYONE HIDE! ITS ALMOST HERE! THE COMMENT SECTION!

Excellent. One very picky thing, though - the surname Lyell rhymes with 'trial'.

Taking a short break from my homework to watch some crash course hell yeah!

Darwin should have changed “most fittest” to “most adapted” so he would have avoided several misconceptions about natural selection. “Most fittest” conjures up super-strong animals. Being super-strong does not necessarily mean you will survive. Being a lion sucks if your only food source is meat and all the meat source is dying out while there are plenty of plants growing around. It boils down to energy balance and adapting to it.

where do i get the little willy statue? i love so much

Great overview of Darwin and his bulldog. Glad you covered them both so much! Also, at the very end, your comments on Social Darwinism were spot on. Glad you didn't gloss over that; it was more important than the religious controversy.

I liked the explanation! I love turtles 😅

Have a great day

I mentioned Wallace during science and no one not even the teacher knew who he was.

And that’s why we give out Darwin awards these days kids...

1:49 our science textbook is called science.

I guess someone could write a fictional book where "Nature" is a deity. If said book becomes massively popular, then it would probably cause too much confusion.

Wait Hank...did you pre-record this? How are you able to record this while on tour for your new book, "An Absolutely Remarkable Thing" that came out September 25 and is available for order now?

my mind has reached peak smarts

The captain of the Beagle was Robert Fitzroy, later to become Admiral Fitzroy. He hated Darwin during the voyage, and as a staunch creationist Jared his theory of natural selection so much, that a possibly apocryphal tale had him walking through a lecture theatre where the theory was being debated, holding a bible above his head and simply screaming the words “The book!” He became the grandfather of modern meteorology, but later took his own life - possibly in part for criticisms levelled at his attempts to produce the first weather forecasts for the Times newspaper - which, it being a nascent science, were prone to inaccuracies and errors. After his death, his office was taken over and turned into the modern met office by none other than one of Darwin’s half-cousins, Francis Galton.

i turn off addblock just for these videos

Ohhh... I know why CrashCourse likes turtles...., It's because Turtles all the way down!

Hank. You are, by far, my favorite KZfaq personality. Awesome!

Q: Why did the creatard jump off the building? A: He thought gravity was "just a theory"

Really embarrassed to point this out, but the map about Wallace's travels mistakenly marks Brunei as Singapore.

Alfred Russel went to my school.

thats why I'm doing homework right now

Gotta love Chuck, right! lol

what about the Webber line along with Wallace's?

O....... thank you for explanation

"which to be honest its more than I had" lolll

I have an anthro midterm on thursday this is so convenient

I have a new hypothesis, skip classes, make C's and be renowned like Charles Darwin

By now we should have lightning bug asses for earlobes, so we can use turn signals in the grocery store.