Genetic drift, bottleneck effect and founder effect | Biology | Khan Academy

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  • Опубліковано 25 гру 2024

КОМЕНТАРІ • 103

  • @Majaschoice
    @Majaschoice 7 років тому +221

    Am I the only one who loves his voice? he is the morgan freeman of science

    • @hayatburak9252
      @hayatburak9252 5 років тому +5

      Mayacocoice and math!

    • @chocolatepoodle6028
      @chocolatepoodle6028 4 роки тому +9

      Definitely not just you! I'm British and I'm obsessed with his voice and accent. He's absolutely mesmerising! (And kind of sexy too...)

    • @akshatsharma5536
      @akshatsharma5536 3 роки тому +2

      Ur not alone 😫

    • @dishhatter
      @dishhatter Рік тому

      I found it soothing.

    • @Paris-et9wn
      @Paris-et9wn Рік тому

      @@chocolatepoodle6028 someone was down bad for the science guy. Found you 2years later in 4k too😂

  • @rifqinor
    @rifqinor Рік тому +9

    to my baby who’s sitting for her finals and studying her best, i wish and pray that you’ll get your dean’s list this year💗

    • @rifqinor
      @rifqinor Рік тому

      @Khira i love you too sayang💗💗

  • @katherinefox297
    @katherinefox297 7 років тому +19

    Definitely my favorite guy to listen to. I've learned so much from him!

  • @languageandmana9255
    @languageandmana9255 Рік тому +7

    I was looking for a video that compares these three concepts and you have it! You are amazing! Please remain FREE and make more advanced medical videos for medical students. If I could afford it, I would have definitely donate to this channel each month but I can't have the bank account to pay in dollar or euro now. But I will within the next five years and one day start to donate to this channel regularly. Thank you for all you do🙏♥✨

  • @idefendyoutubefromredditer640
    @idefendyoutubefromredditer640 7 років тому +8

    the teacher in this video has such a unique voice and presents lectures beautifully!

  • @vedant309
    @vedant309 3 роки тому +7

    Explained so nicely. Great effort. Thanks

  • @ghsjgsjg53chjdkhjydhdkhfmh74
    @ghsjgsjg53chjdkhjydhdkhfmh74 5 років тому +10

    Wow😍 thank you so much I never understood genetic drift before!!

  • @bigfootpegrande
    @bigfootpegrande 7 років тому +6

    More than randomness in the outcome of which individuals from the sample reproduce, Random Genetic Drift can be thought as randomness in the outcome fecundation from the heterozygotes: Even though it is expected a 1:1 ratio of transmission of each allele, the lesser this genotypes reproduces, the larger the chance its contribution to the next generation's gene pool will be off 1:1.

  • @soniakhan1635
    @soniakhan1635 7 років тому +3

    Didn't understand this until now thankyou!

  • @johncarlosbgumbao
    @johncarlosbgumbao 3 роки тому +1

    0:54 The laugh was great welcome to this lesson.

  • @Breyerlover4ever23
    @Breyerlover4ever23 6 років тому +4

    This is so helpful, I finally understand this!

  • @japanesereadingandwriting
    @japanesereadingandwriting 2 роки тому +1

    Thanks

  • @dishhatter
    @dishhatter Рік тому

    Thank you. Very soothing voice and nice handwriting.

  • @shirlbristow9782
    @shirlbristow9782 5 років тому +2

    Wow! I've never had such a selection whith captions.

  • @yannickinspain
    @yannickinspain 5 років тому +2

    That was so interesting. So much stuff makes sense thx to your work. Thank you.

  • @jsj0468
    @jsj0468 3 роки тому +1

    Great video! It was really helpful

  • @rogelindabarraza1993
    @rogelindabarraza1993 4 роки тому +1

    Thank you so much for this video. Excellent explanation!!!!

  • @katieware3479
    @katieware3479 5 років тому +2

    BLESS YOU FOR THIS

  • @ohlookitsrosie
    @ohlookitsrosie Рік тому

    thank you!!! ❤

  • @HorkSupreme
    @HorkSupreme 8 років тому +3

    I suppose an example of genetic drift and natural selection (and artificial) is a recovery project for a species of birds (I don't remember the details). Some eggs were laid on the outer parts of the nest, which would not have hatched, but were moved to the middle by the people to have more birds survive. After some generations a majority of the birds were laying eggs on the outside. So the people stopped moving the eggs at all and after some time most eggs were laid in the middle of the nest.

    • @kassandraw8844
      @kassandraw8844 8 років тому +3

      the new zealand chatham island black robin :)

    • @who5563
      @who5563 3 роки тому +1

      Sosig

    • @HorkSupreme
      @HorkSupreme 3 роки тому +1

      @@who5563 WHERE'S THE LAMB SAUCE?

    • @who5563
      @who5563 3 роки тому +1

      @@HorkSupreme ikr

  • @neetaiimsbattlefield3737
    @neetaiimsbattlefield3737 2 роки тому

    Lots of love from kashmir

  • @hanamostafa5268
    @hanamostafa5268 4 роки тому

    Thanks so much that was helpful.....!

  • @shaniaturner7571
    @shaniaturner7571 6 років тому +2

    I thought genetic drift was a category under bottleneck effect. I thought bottleneck effect was simply the decrease of a population and alleles.

  • @funfun6209
    @funfun6209 6 років тому +1

    Best easy to understand

  • @mdj8934
    @mdj8934 Рік тому

    Natural selection (selection of favorable traits) + genetic drift (randomness)= evolution
    So, evolution is not equal ONLY to natural selection (as we often equal those), but also it has influence of randomness or genetic DRIFT.

  • @yahwayapps7947
    @yahwayapps7947 3 роки тому +2

    Great!, Can we account genetic drift for the emergence of new Kind/ Family or new species only ?

    • @antiHUMANDesigns
      @antiHUMANDesigns 3 роки тому

      Linnéan taxonomy is obsolete, it doesn't work very well with evolution, since it was only designed to be a kind of snapshot of what life forms exist today.
      In modern science, we use cladistics, instead. A system of branching lineanges.
      So, your question doesn't make sense in modern science.

    • @yahwayapps7947
      @yahwayapps7947 3 роки тому

      @@antiHUMANDesigns cladistics at the end of the day is based on assumptions, not an evidence. Where are all the intermediate fossils?

    • @antiHUMANDesigns
      @antiHUMANDesigns 3 роки тому

      @@yahwayapps7947 Based on what assumptions?
      Clades is phylogeny is derived from genetic analysis.
      Take all of the DNA we have sequenced from all different species, plug them into a computer program, and the program spits out a phylogenetic tree that represents their relationships, each with a confidence level.
      The tree you get matches what we see in the fossil record, as well.
      Where are the intermediate fossils? Everywhere. They're all intermediate. Have you ever seen a fossil that's not intermediate?

    • @yahwayapps7947
      @yahwayapps7947 3 роки тому

      @@antiHUMANDesigns the program doesn't magically build the tree, it needs an algorithm to run - which is given by Human.

    • @yahwayapps7947
      @yahwayapps7947 3 роки тому

      @@antiHUMANDesigns the reason we have the concept of punctuated equilibrium is fossil records are not supporting the macro evolution hence, no tree. So better to switch to an assumption /algorithm to draw the tree. You are classifying them based on how close they are becuase first you assumed all life branched our from single/common ancestor

  • @Gembappe
    @Gembappe 8 років тому +1

    Why did you guys delete the last video on Evolution?

  • @JA-xv3qp
    @JA-xv3qp 4 роки тому

    great video!!

  • @yiannizs
    @yiannizs 6 років тому +1

    What is the reason of the actual population size being smaller than the effective population size? Any answers will be really heplful

  • @kaharshital2724
    @kaharshital2724 5 років тому

    Amazing video

  • @Sana-N99
    @Sana-N99 5 років тому +2

    Would the recent Austrialian bush fire be an example of the bottleneck effect?

    • @throspillow
      @throspillow 4 роки тому

      probably, i mean i'd say so

  • @nick_osas
    @nick_osas 4 роки тому

    Salman, the man

  • @tayahiabu2418
    @tayahiabu2418 2 роки тому

    whats up with the graph being 3:7 when there are 5 with a ressive trait and 5 without? and there is only 1 white rabbit??

  • @marianna094
    @marianna094 3 роки тому +1

    1.45 this is discrimination against pink and yellow dots

    • @marianna094
      @marianna094 3 роки тому +1

      3.56 "whether you're brown or whether you're white, it confers no advantage." yessir

  • @omymamohamed29
    @omymamohamed29 Рік тому

    ❤❤❤

  • @Yomomma-jf9iy
    @Yomomma-jf9iy Рік тому

    I don't know. Japanese and, some, south Korean mutations for lack of smelly body odor compared to the Indian subcontinent's tendency for strong body odor... I don't think it was random chance. Some women are picky, some are not. Some women are forced to marry, others are not.

  • @matthewklassen806
    @matthewklassen806 6 років тому

    All horizontal or loss of information. Where do we gain information?

    • @rmsanche
      @rmsanche 6 років тому

      mutation.

    • @slaughtermate
      @slaughtermate 5 років тому +1

      The lecture was not about mutation and positive selection, only the potential loss of genetic variation.

  • @toserveman9317
    @toserveman9317 2 роки тому

    "Drift" means ratio change in phenotype (genotype/ allele expression) of a population: e.g flower BED changing from purple to white over generations. (Ratio -- 9 to 1, then 8 to 2, etc.)
    It doesn't tell us whether the phenotype ratio-change is being selected for or a spandrel.
    The way some define "DRIFT" makes it seem like spandrel development is an evidenced fact rather than marxist [e.g gouldian] conjecture.
    ...
    Similar thing happened with "adaptation" and "sexual selection." ...The "marxists" just don't care about anything other than politics and cope. And don't get me started on "disorder."
    ....
    When asserted-spandrels are studied they are found to be selected traits.
    I don't know of any true spandrels other than bone color and MAYBE momma whale/ dolphin (and maybe her sonS) protection of a dead calf.

  • @calebpayne252
    @calebpayne252 3 роки тому

    God gene

  • @Samsalla71
    @Samsalla71 6 років тому

    Whats the narrators name

  • @jbignJesus
    @jbignJesus 8 років тому

    *natural selection is a mechanism of creation and not exclusive to the THEORY of evolution

    • @commanderkei9537
      @commanderkei9537 8 років тому +3

      N o

    • @Akfloatable
      @Akfloatable 8 років тому

      No, natural selection is not a mechanism of the creation HYPOTHESIS.

    • @gabek1381
      @gabek1381 8 років тому +2

      +ak Hypotheses can be falsified. *Creation fable.

    • @gabek1381
      @gabek1381 8 років тому

      +ak Hypotheses can be falsified. *Creation fable.

    • @boglenight1551
      @boglenight1551 8 років тому +2

      Please don't go correcting people, there's a reason why the academic world is atheist, perhaps you should think about that.

  • @calebpayne252
    @calebpayne252 3 роки тому

    Lgbtqia rainbow species

  • @OwenChiu
    @OwenChiu 2 роки тому

    sheesh

  • @MyFather7865
    @MyFather7865 6 років тому +1

    Khan is a MUSLIM Name 😂😂 are you MUSLIM sir

    • @AJ-fv9ll
      @AJ-fv9ll 6 років тому

      No, it comes from the turkish word meaning chief or ruler.

    • @MyFather7865
      @MyFather7865 6 років тому +1

      @@AJ-fv9ll yeah but it's a MUSLIM name

    • @ashirt2100
      @ashirt2100 6 років тому

      @@MyFather7865 Yeah he is a muslim.His mother is from India (Bengal)and father is from Bangladesh.

    • @MyFather7865
      @MyFather7865 6 років тому +1

      @@ashirt2100 how do you know. He is American

    • @wasiantalks
      @wasiantalks 4 роки тому

      @@MyFather7865 Search up where is Salmon Khan from

  • @sciencenerd7639
    @sciencenerd7639 2 роки тому

    thanks

  • @kotisol4773
    @kotisol4773 11 місяців тому

    ❤❤❤