Genetic drift, bottleneck effect and founder effect | Biology

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

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8 жыл бұрын

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Genetic drift, bottleneck effect and founder effect
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Пікірлер: 103

@Mayacocoice 7 жыл бұрын

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

@hayatburak9252 5 жыл бұрын

Mayacocoice and math!

@chocolatepoodle6028 4 жыл бұрын

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 3 жыл бұрын

Ur not alone 😫

@dishhatter Жыл бұрын

I found it soothing.

@Paris-et9wn Жыл бұрын

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

@katherinefox297 7 жыл бұрын

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

@rifqinor Жыл бұрын

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 Жыл бұрын

@Khira i love you too sayang💗💗

@languageandmana9255 Жыл бұрын

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🙏♥✨

@ghsjgsjg53chjdkhjydhdkhfmh74 4 жыл бұрын

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

@yannickinspain 4 жыл бұрын

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

@idefendyoutubefromredditer640 7 жыл бұрын

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

@Breyerlover4ever23 6 жыл бұрын

This is so helpful, I finally understand this!

@vedant309 3 жыл бұрын

Explained so nicely. Great effort. Thanks

@rogelindabarraza1993 4 жыл бұрын

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

@soniakhan1635 7 жыл бұрын

Didn't understand this until now thankyou!

@bigfootpegrande 6 жыл бұрын

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.

@hanamostafa5268 3 жыл бұрын

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

@jsj0468 3 жыл бұрын

Great video! It was really helpful

@katieware3479 4 жыл бұрын

BLESS YOU FOR THIS

@funfun6209 6 жыл бұрын

Best easy to understand

@ohlookitsrosie Жыл бұрын

thank you!!! ❤

@japanesereadingandwriting 2 жыл бұрын

Thanks

@JA-xv3qp 3 жыл бұрын

great video!!

@johncarlosbgumbao 2 жыл бұрын

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

@dishhatter Жыл бұрын

Thank you. Very soothing voice and nice handwriting.

@kaharshital2724 4 жыл бұрын

Amazing video

@sciencenerd7639 2 жыл бұрын

thanks

@shirlbristow9782 5 жыл бұрын

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

@yiannizs 6 жыл бұрын

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

@Gembappe 8 жыл бұрын

Why did you guys delete the last video on Evolution?

@shaniaturner7571 6 жыл бұрын

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

@HorkSupreme 8 жыл бұрын

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 7 жыл бұрын

the new zealand chatham island black robin :)

@who5563 2 жыл бұрын

Sosig

@HorkSupreme 2 жыл бұрын

@@who5563 WHERE'S THE LAMB SAUCE?

@who5563 2 жыл бұрын

@@HorkSupreme ikr

@nick_osas 3 жыл бұрын

Salman, the man

@neetaiimsbattlefield3737 2 жыл бұрын

Lots of love from kashmir

@tayahiabu2418 Жыл бұрын

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??

@Sana-N99 4 жыл бұрын

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

@throspillow 3 жыл бұрын

probably, i mean i'd say so

@yahwayapps7947 3 жыл бұрын

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

@antiHUMANDesigns 3 жыл бұрын

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 2 жыл бұрын

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

@antiHUMANDesigns 2 жыл бұрын

@@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 2 жыл бұрын

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

@yahwayapps7947 2 жыл бұрын

@@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

@kotisol4773 6 ай бұрын

❤❤❤

@matthewklassen806 6 жыл бұрын

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

@rmsanche 5 жыл бұрын

mutation.

@slaughtermate 4 жыл бұрын

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

@mdj8934 Жыл бұрын

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.

@kofipapa2886 Жыл бұрын

There are even other mechanisms

@marianna094 3 жыл бұрын

1.45 this is discrimination against pink and yellow dots

@marianna094 3 жыл бұрын

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

@toserveman9317 2 жыл бұрын

"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 3 жыл бұрын

God gene

@Samsalla71 6 жыл бұрын

Whats the narrators name

@takshashila2995 5 жыл бұрын

Sal Khan

@takshashila2995 5 жыл бұрын

Founder of Khan Academy

@Yomomma-jf9iy 10 ай бұрын

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.