Phylogenetic trees | Evolution | Khan Academy

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Learn how to read and draw phylogenetic trees, or cladograms.
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Опубликовано:

15 июн 2024

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Комментарии : 137

@ziolp 7 лет назад

This is very clear and helped me understand the phylogentic tree for my exam. Also, your voice is crisp and smooth. So that helped too.

@jessejaja5322 5 лет назад

+X-Ray Crystallography if you want to learn focus what is been thought than the accent.Go to a language section if interested in language

@lancetschirhart7676 4 года назад

@Aliyah ZSB My best guess is that he's one of those people in this emergent culture who loves to publicly express racism because he wants to "balance out" those who he believes cry wolf. Even if there are a lot of people crying wolf, it doesn't make much sense to me. It's also an effective mechanism to express his feelings without reproach if he genuinely is a racist. Just one man's interpretation, though.

@allscool-4131 3 года назад

@X-Ray Crystallography That wouldn't be diverse at all, diversity is multiple cultured people. One African is the same amount of diversity as one American.

@luckycharms8020 3 года назад

@X-Ray Crystallography Keep going you've almost supplied my daily sodium intake

@Angel-hv9jm 5 лет назад

You explain this topic better than our biology teacher.

@XLV0 Год назад

you speak for all of us

@lauragordon6414 6 лет назад

The instructor moved at a sufficient enough pace to avoid distraction. This person also spoke in basic terms which enhanced absorption of the material. Very well done! Thank you!

@MrKarenke0912 4 года назад

watching this 4 hours before my first-year biology exam

@quincyjenkins981 4 года назад

i hope u did well lemme know im watching this15 hours before mine

@noorrandhawa1536 4 года назад

same lol

@benorourke_ 4 года назад

First year of university/college?

@adhyakasamsetty6575 3 года назад

SAME mine is in 12 hours

@soheliroy8651 Год назад

So how was your college life!?

@wolfyyt1926 4 года назад

I know it’s not this video but my sister just wears her earbuds to her stats class and she listens to you instead of her teacher. She has an A while everyone else has a C

@michii3467 3 года назад

no way.... imma do that too

@houstinswan9985 3 года назад

Oof

@marissabell605 3 года назад

Your voice is so soothing. You have gotten me through Chemistry, math and biology. You are a savior before exams.

@anitaarnold6534 2 года назад

Thank you! When I don’t understand something in biology (or any subject really) I hop on over to RU-vid to look you up. I appreciate your explanations. They make more sense to me!!! When the question was asked, if you could meet anyone in the world that was living or dead, I said, “Mr. Kahn”. I admire your gift and willingness to share your knowledge and expertise with others with no expectation in response. Thank you!!! I appreciate you!

@dilkhush9804 4 года назад

This is a platform where I learned Biology for my first year. Khan Academy is the best , main thing is its totally free.

@keidenpark7265 6 лет назад

Oh my word thank you so much. This was clear and very understandable. I hope I can get it right for my assignments and exams cause the organisms I’m getting are difficult.

@hiromishimada7200 5 лет назад

"parsimony might sound good but actually it means cheap " i laughed hard at that hahahaa

@Slimeman2point0 4 года назад

I thought he said cheese

@minney4364 5 лет назад

Not all heroes wear capes! Thank you so much for this video!

@mohammadalgoul3892 5 лет назад

this is just amazing and very clear thank you so much

@deleteeeeeeed 7 лет назад

sal once again ur doing god's work bless up. making first year uni bearable

@juan56646 3 года назад

@Belfast Blue Are you good?

@rosakuhn5274 6 лет назад

Very helpful. Thank you for actually showing your thought process while creating the cladogram. :D

@villainousshowerhairclump5871 5 лет назад

thank you!! I have a biology test and was away when my teacher taught this; this helped me understand it, so hopefully, I'll get a good grade!

@KimmayTran 4 года назад

ya, did u?

@LilTaco-_- 4 года назад

LuciferPoptarts 666 did u?

@KimmayTran 4 года назад

he's died

@jazzybear5509 4 года назад

Do you like know everything? Lmao everytime I look for something on RU-vid for school you come up. I was surprised to see you even teach college algebra. Thank you for your videos!

@tiffanynorris1370 6 лет назад

More of this!!!! Loved it.

@anxne2012 7 лет назад

Thank you so much! This was so clear, helped a lot!

@Broccoli821 7 лет назад

Great explanation!

@alisonmalekian8811 4 года назад

so you basically look for most common to least. Ugh I have such a hard time with these trees like I don't see the point of this but this video helped me get a better understanding

@EclipZeMuzik 6 лет назад

i really like this keep up the good work!

@kathyyszn 4 года назад

this helped a lot, thanks!

@pbscampus 3 года назад

I ran away from the textbook when I couldn't get it. I came here, and said " Aha!". Thank you.

@jessejaja5322 5 лет назад

It's like this guy is my classmate.He explains every problem directly as if he was in my class Be it chemistry, Maths or Bio

@aditivasmatkar6874 6 лет назад

Thank you Sal for making such helpful videos

@phenomenalivan1779 2 года назад

Please which app do you use to make your tutorial videos

@snapple5950 4 года назад

I love Khan Academy because it always tells me what I need to know in detail without any unneeded details! I am always able to learn exactly what I need to thanks to them. Thank you, Khan Academy. :)

@meda04 8 месяцев назад

very easy to understand thank you

@jasminecox643 4 месяца назад

I LOVE Khan Academy! I learn so much better.

@aidenmohrmann1850 6 лет назад

Thanks so much for your videos

@halstenblack9258 4 года назад

That Sea Bass is a least a C+

@lizzywilliams 2 года назад

i spy another animal crossing player

@sciencenerd7639 2 года назад

great video, thanks

@melisabuken7744 6 лет назад

Thank you so much!!!

@jeanettequintero2313 6 лет назад

Very helpful.

@evanb.9122 2 года назад

The way he drew the line under the word parsimony at 6:00 was odly satisfying

@spicymeatballs2thespicening Год назад

how does he do it so straight I wish I could do that 🍝😭

@rustyshackleford054 6 месяцев назад

Something I have never been able to wrap my head around with phylogenies - when there is a speciation event, on a phylogeny, we show that as a fork. And we always just say, "some common ancestor, species A" evolved into species B and C, which will be named. But we never can say who soecies A was. Do we actually ever know who species A was? And what if we do know who species A was and know the exact link from species A to species B? How do we show that on a phylogeny?

@trenttwoider9346 7 лет назад

Another wonderful video

@MsChantae 5 лет назад

Thanks!

@juanpablotorresdelacuadra9856 3 года назад

thanks for the video. If this video wouldn´t exist, I will be ALL MY LIFE asking me a question that will be: what is the phylogenetic tree? thanks so much =).

@Lowzenza4 7 лет назад

What program do you use to do this?

@siffo10 7 лет назад

Lots! One popular one is MEGA

@dtrcs9518 6 лет назад

using mega7 right now, it's usually more user-friendly

@Jactos1691 5 лет назад

i use the program imagin-ation seems to work just as well.

@uchechiudeafor7686 11 месяцев назад

Thank you sir,our tutors in school are making things really difficult for students

@trishamedeiros1459 5 лет назад

I love you, man.

@shelleylauritsen4169 5 лет назад

Question for this cladogram - doesn't everything to the right of the organism you are comparing have the same recent ancestor and have the same number of similar traits. Wouldn't this make each of those things equally related- for instance the sea bass and the eagle or the sea bass and the antelope. Both have the same most recent ancestor and have the same number of shared traits?

@peternyikos8020 Год назад

The answer is Yes to "same recent ancestor"; this is exactly how cladists define "equally closely related," except they use the more precise designation Last Common Ancestor (LCA for short). The question "same number of shared traits" works for this highly simplified example with just four traits, but might fail in a tree where many more traits are included.

@IchsanulIqbal-yv2ip 2 года назад

love it

@nothanks3724 5 лет назад

yay thank you!

@JenDominance_Occupy 3 года назад

this great

@snapple5950 4 года назад

Also that Antelope be looking like Rudolph ngl

@km2052 7 лет назад

awesome

@japanesereadingandwriting 2 года назад

👍

@70snostalgia 4 года назад

Thanks.

@aufa2119 7 лет назад

oversimplification? nah. its okay as long as we understand it.

@autumnd.2990 4 года назад

Thank you. God is good.

@Dr.IanPlect Год назад

your god is mythology

@SamStarbucker 6 лет назад

I can finally breathe!!!

@omgchocolate4857 5 лет назад

How would it change if we included a species with feathers but no gizzard? Would feathers become a separate branch independent of the gizzard branch? If so, how does one account for the fact that the bald eagle has a gizzard?

@user-nn3bp8fy4e 9 месяцев назад

Watching this 1 hour before test🙋‍♂️

@katherinemcferrin6446 5 лет назад

Could antelope and alligator/bald eagle’s branch be switched around? Or does that order matter?

@Dr.IanPlect Год назад

In that layout they can be switched and have the same meaning.

@sacul1291 5 лет назад

1:19

@BrendanMcClelland 6 лет назад

The bald eagle and the alligator are actually related. They’re both archosaurs.

@harv029 4 года назад

is the sea bass more related to a bald eagle or a lamprey?

@Dr.IanPlect Год назад

eagle

@thegoodfellas9746 4 года назад

NOICE

@Maryam-kg7vp 5 лет назад

prisomny : is the simplest explanation of photogenic tree ??

@Dr.IanPlect Год назад

'prisomny' 'photogenic' - what planet are you from?

@TomWinkler-mz9yp Год назад

What if the common ancestor is a species that is still living? How would it look like in a phylogenetic tree? For example if species B evolved from Species A but species A still exists and lives alongside it. Then species A is the common ancestor? How would that be drawn?

@Dr.IanPlect Год назад

Extant or extinct is of no relevance! There are lots of examples of B evolving from A where A is still living! Wolf-dogs, brown-polar bear, jungle fowl-chicken.

@ollieanabella264 3 года назад

what's the basis for placing the bird and the alligator before the antelope?

@Dr.IanPlect Год назад

It's just illustrating the branching off of sauropsids and synapsids, the parent lineages of reptiles and mammals respectively.

@beautyblueable 7 лет назад

Um I'm pretty sure the tree you drew/made is a cladogram not phylogenetic tree

@zoemorley3617 7 лет назад

Yeah this does appear to be a cladogram instead of a phylogenetic tree thanks

@burnsloads 6 лет назад

Yeah, well, ur gay.

@sniperzBAK 6 лет назад

They show the same information...

@rosakuhn5274 6 лет назад

My understanding is that a phylogenetic tree describes the development of species from at least one common ancestor based on the descendence theory (=all species derive from one common ancestor). A cladogram shows the relationship between different species and the extent in which they are related. Which means that what was being drawn in the picture could have been both at the same time because both concepts do not contradict each other. Although there is a different type of phylogenetic tree which not only shows the relationship (as a cladogram does) but also the length of the lines represent the passed time. I am not sure what that one is calles though :)

@Chester_Cheeki 5 лет назад

@@scqrcity4632 Actually, they do. Cladogram and the phylogenetic tree shows traits based on similarity, the phylogenetic tree is just also based on the time of evolution.

@nikkiandress2530 Год назад

What characteristics seperate marsupials from chimpanzees, cows,humans and whales ??

@outlander271 4 года назад

Ockham’s razor.

@waliul280 5 месяцев назад

In short, the entire phylogenetic tree of life is based upon the assumption that every living thing evolved from a universal common ancestor (which is a single cell).

@patrickndongache8798 6 лет назад

Sir, could we also have the Cladogram as; 1. The Lamprey branches off first because is does not share any characteristic with the rest of the organisms 2. The Sea Bass is second because it has jaws as the others but lacks lungs 3. The Antelope is third because it has lungs but lacks a Gizzard. However, it develops fur along the line 4. The Bald eagle fourth because it has a Gizzard but developed feathers along the way 5. Then, fifth will be the Alligator which remains on the main line of descent with the Gizzard I will appreciate your feedback Thank You

@MasterPigeonXD 6 лет назад

Ndonga Patrick I got the same answer and I believe it is correct. You can pivot the node at 180 degrees (the pink one just after lungs evolved) and it will give you the same tree.

@pesenna 6 лет назад

This way is also correct. Actually you just rotated the position of the terminals of the tree but the relationships between them remains the same no matter how you rotate them, because in the end it represents the same phylogenetic tree.

@Katiekazoo806 4 года назад

Can there be another way to draw the phylogenetic tree?

@Goldblasterblaze 4 года назад

Yes

@justinspearlord 6 лет назад

Even if you don't believe in evolution you unfortunately have to know this sort of stuff for exams :(

@JungleJargon 4 года назад

"Looks like" is not evidence. You can't get written instruction that is not there. You can only change what is already there.

@silverfoot6079 4 года назад

I think it's interesting to note the similarities between an eagle and an alligator. Considering that both lizards and birds are descendants of dinosaurs, it is not that bizarre to compare an eagle and an alligator or a chicken and a gecko.

@Dr.IanPlect Год назад

Lizards are NOT descendants of dinosaurs.

@BrendanMcClelland 6 лет назад

And one of the five species you listed is actually a dinosaur.

@Mrojersey 5 лет назад

you said an outgroup is the exact opposite thing that my textbook just told me. So one of yall wrong.

@rudjard18 6 лет назад

luv u

@d34thw4tch6 Год назад

I thought this was a cladogram

@sara-zb1ye 4 года назад

online school tings

@mikelombard21 5 лет назад

This confuses me. Do we not have tons or at least some fossil and genetic evidence to accurately place things where they belong? You keep stressing the hypothesis part but does not the fact we are so genetically identical to chimps help place us in phylo trees? You can do it strictly based on the traits but is the real phylo tree with accurate representations not actually being compiled slowly but surely scientists? We share Dna with all life on this planet, going back from bacteria to archaea and do on. Can we not now partly place many large divergences accurately? It may take mapping the genetic code of every species which is ridiculous there is quite possibly too much biodiversity, but do we not have some evidence? Is there no accuracy to what we are mapping? Humans share dna with bananas but much more dna with all mammals for example. Like how sibling are more closely related than cousins genetically. In reality and not hypothetical examples such as this do we not have some credence behind when scientists produce phylo trees.

@natashanajam3499 7 лет назад

why dis vid got no views? WTF youtube problem ?

@edgarvillalba4234 7 лет назад

because people prefer to see other people talking about sh*t rather than learning new things about science

@lymbopurgatum1235 7 лет назад

@DAVIDPETERS12C 5 лет назад

Just so you know, molecular evidence (genomic testing) works great with humans and closely related taxa, but fails completely in deep time studies with Mesozoic fossils.

@Dr.IanPlect Год назад

a point of obfuscation by an oxygen thief

@DAVIDPETERS12C Год назад

@@Dr.IanPlect ---: ad homineum arguments are found on middle school playgrounds, so inference tells us you are not yet old enough to vote. Keep studying and don't lose that schoolboy charm, you cute little bugger. : )