Evolution: It's a Thing – Crash Course Biology #20

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Hank gets real with us in a discussion of evolution – it’s a thing, not a debate. Gene distribution changes over time, across successive generations, to give rise to diversity at every level of biological organization.

Table of Contents
1) The Theory of Evolution 1:49
2) Fossils 2:42
3) Homologous Structures 4:36
4) Biogeography 7:02
5) Direct Observation 8:52

References:
http://www.hisl.ent.msu.edu/discussion/Miller_et_al_2006.pdf
http://www-personal.umich.edu/~gingeric/PDGwhales/Whales.htm
http://evolution.berkeley.edu/evolibrary/article/history_16
http://www.thomsonedu.com/community/russell/Russell_19_401-418%2012.pdf
http://articles.latimes.com/2010/jul/28/science/la-sci-marsupial-20100728
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2555653/pdf/bullwho00311-0137.pdf
http://news.nationalgeographic.com/news/2008/04/080421-lizard-evolution.html

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25 Comments

  1. The chimpanzee 98% thing is a myth. And needs to disappear. Otherwise good show.

    I wish people would compare different tree's of historical evolution from different fields of study. This is beyond powerful imagery, as they all align.

  2. Why do people even bother arguing about this on the internet anymore? Willfully ignorant people are going to remain willfully ignorant on the evidence and reasoning of evolution as long as they continue to suck up religious dogma that has stunted science for centuries. Can we save our breath? These people aren’t going to become world-renown biologists any time soon, and these tedious internet arguments just aren’t worth ones frustration and mental energy considering they end up amounting to nothing of value.

  3. Thanks for the video. I don`t consider the evidence that creatures have similar organs and structures as strong evidence to recognize the existence of evolution because a car manufacturer has different types of cars but they have similar frames. That doesn`t change the fact that the same manufacturer created them.
    I guess we are defining evolution as laws in-universe. Those are laws that work in the universe they are not a lawmaker. By the way, don`t make the evolution as evidence not to believe in God. We should never forget that when we read an incident we try to see the actor or meaning that doesn`t appear on the face of an incident or a book. All of these things that happen in the universe must have a meaning that we couldn't see. We shouldn`t ignore that fact. If we ignore the fact then what is the meaning of life if we will die and spoil under the earth.

  4. Not open for debate? Shouldn't people be encouraged to try to disprove a theory? Are you really 100% sure you can trace our origins over 3.5 billion years to a single granddaddy organism? Seems like there is plenty of room for error there. The microevolution (natural selection/survival of the fittest?) you talk about I agree with: mosquitoes developing resistances; lizards becoming vegan hipsters. But does this prove beyond all doubt that a hippo can evolve into a whale? Can a T.Rex become a chicken? Maybe. This doesn't seem like 100% settled science to me, though. Doesn't seem anywhere close to settled. If I'm missing something please enlighten me.

  5. Humans or (monkeys) don’t know what to do with themselves so they base their theoretical safe place and determine there’s a god beyond the only livings things on this planet.

  6. Hey guys I have created a basic but detailed sort of script that Hank has seemed to have said in order to make a good description in case you weren't able to keep up with what he was saying. I hope this helps as it took a while to make.

    THE THEORY OF EVOLUTION
    *The theory of evolution is the, evolution is the idea that gene distribution changes over time, however the theory of evolution is a large set of ideas that integrate and explains a huge mass of observations from different sciences from palaeontology to anatomy. Thus the theory of evolution explains many things that we as humans have seen and observed for thousands of years, it’s the theory that precisely explains how all life on earth is so diversely complex and different.
    *

    EVIDENCE 1: FOSSILS
    *Fossil record shows that organisms living long ago were different from those we see today. When scientists first discovered dinosaurs they thought they were all giant iguanas, however it wasn’t until the dinosaurs with 2 legs started coming up that scientists had to grapple with he fact that organisms from the past where somewhat similar to animals today, however they have al gone extinct therefore they must have evolved to survive and be the animals we see today. Another example is how scientists found out Whales used to walk, they first found an old fossil that in fact had vestigial leg bones that fell into the same category of whales, then they later found an older fossil that had whole legs, as well as a pelvis, however the pelvis wasn’t fused to the backbone therefore still swam like a whale. In addition this fossil still had ankle bones that were in turn unique to the same family that included pigs, hippos, bison and deer.
    *

    EVIDENCE 2: HOMOLOGOUS STRUCTURES
    *Homologous structures are the structures of our bones and things for example the difference between this human arm and bat arm, they both have the Exact same structures that you can see is colour coded with a long bone at the hinge, 2 smaller thin bones connecting to the hands, which has a group of smaller grouped together bones, then the fingers. Although all organisms will be using their limbs for different purposes, due to the very similar structure, we can see how really close we are. This is the same for DNA/RNA, all living things on earth has DNA and/ or RNA, the fact that we all use the same molecules shows how alike we all are. However, if we look into the sequencing of a species DNA we can see how really related we are.
    *

    EVIDENCE 3: BIO-GEOGRAPHY
    *When it comes to species that are very related to each other and their distribution around the world is explained very well by the evolution. Animals that are the most similar tend to be found in the same regions, because evolutionary change is driven by geographical change. When organisms are restrained and separated by rivers or mountains, they take their own evolutionary courses. However, in this type of time period we are talking about, change happens over a much larger period of time, and it is in fact often due to continental drift. For example, the reason why Australia has kangaroos, Koalas, and many other unique animals, is because when Australia started breaking off and becoming it’s own island all the animals that stayed o the mainland were killed off over the years whilst the animals that stayed on the Island slowly breaking away stayed alive becoming the animals we know in Australia today.
    *

    EVIDENCE 4:
    *There are many things we have seen in our own lifetimes that are amazing examples one of the most common being the resistance to drugs and chemicals. In 1959 a study in India found that DDT killed 95% of mosquitoes on the first application, those that survived reproduced and passed on their genetic resistance to the insecticide. Within a year DDT was killing 40% of the mosquitoes and it continued to drop. We have also observed larger animals such as the Italian Wall Lizards, which were originally insect eaters, were moved from one island of the coast to the other. 30 years later, the immigrated Lizards have changed their entire digestive systems and effectively had made their own fermenting chambers to maximise energy and digested the islands main food source, plants.
    *

    Hope this helps anyone attempting to create a PowerPoint or something that needs some sort of text to go off. Leave a like if this helps it took a while XD

  7. Complex organization can only come from intelligent design. Left to themselves, all things in our universe will fade away into useless mush. Not even life can prevent it for long. ONLY an intellect can reverse the process of intentional construction. Not one incident of spontaneous generation of a complex organized system that has EVER been seen. With good reason. Its IMPOSSIBLE. And since this is more important to understand, i'll point out a common misconception that has fooled many an intelligent person into believing it HAS happened before. This subject is evolutionary theory, and more specifically, the difference between MACROevolition and MICROevolution. It's really easy if explained in simple terms. MACROevolution is when a lower species gains complexity and develops into a higher species. MICROevolution is the scientific term for minor changes in organisms. It cannot change a species into a better one, but it can make changes that better suit the animal. I could describe more differences, but I don't have the time. in summery, MICROevolution uses genetic information ALREADY PRESENT in the animal to allow small changes in the animal's characteristics while MACROevolution depends on NEW INFORMATION forming by accident. sometimes, an an information – losing mutation my give an animal a survival advantage over its peers, but MACROevolution depends upon having, not only a survival advantage, but also an increase in information and complexity. There's obviously a problem then. MACROevolution depends on blind chance. And I've learned that when things are left to chance ( according to the laws of the universe ) they have always become LESS complex, not MORE complex. In addition, MACROEVOLUTION HAS NEVER BEEN OBSERVED. Therefore, MACROevolution is a FICTION. Unfortunately, MICROevolution is often used to "prove" that MACROevolution is a FACT. Even the term MICROevolution is misleading. They are two very different ideas. One happens to be valid, the other is impossible.

  8. If evolution is a fallacy, then why do humans have so many meaningless body parts that just conveniently have use in primates and other mammals who we just happen to share an inordinate amount of DNA with?

    1. Coccyx
    2. Tonsils
    3. Plica semilunaris
    4. Appendix
    5. Wisdom Teeth

    God would not just give us useless body parts for no reason. Sorry.

    Oh btw there are more useless body parts than I listed here but these are just a few that serve no purpose but to burden and harm humans.

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