Understanding and building phylogenetic trees | High school biology | Khan Academy

[@ziolp]

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]

+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]

@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]

@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]

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

[@gelivu]

You explain this topic better than our biology teacher.

[@iblamexlv]

you speak for all of us

[@lauragordon6414]

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]

watching this 4 hours before my first-year biology exam

[@quincyjenkins981]

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

[@noorrandhawa1536]

same lol

[@benorourke_]

First year of university/college?

[@adhyakasamsetty6575]

SAME mine is in 12 hours

[@soheliroy8651]

So how was your college life!?

[@marissabell605]

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

[@dilkhush9804]

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

[@hiromishimada7200]

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

[@Slimeman2point0]

I thought he said cheese

[@anitaarnold6534]

Thank you! When I don’t understand something in biology (or any subject really) I hop on over to KZbin 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!

[@keidenpark7265]

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.

[@villainousshowerhairclump5871]

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]

ya, did u?

[@LilTaco-_-]

LuciferPoptarts 666 did u?

[@KimmayTran]

he's died

[@wolfyyt1926]

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]

no way.... imma do that too

[@houstinswan9985]

Oof

[@deleteeeeeeed]

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

[@juan56646]

@Belfast Blue Are you good?

[@jazzybear5509]

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

[@alisonmalekian8811]

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

[@minney4364]

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

[@pbscampus]

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

[@halstenblack9258]

That Sea Bass is a least a C+

[@lizzywilliams]

i spy another animal crossing player

[@jessejaja5322]

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

[@phenomenalivan1779]

Please which app do you use to make your tutorial videos

[@evanb.9122]

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

[@spicymeatballs2thespicening]

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

[@mohammadalgoul3892]

this is just amazing and very clear thank you so much

[@jasminecox643]

I LOVE Khan Academy! I learn so much better.

[@snapple5950]

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. :)

[@EclipZeMuzik]

i really like this keep up the good work!

[@uchechiudeafor7686]

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

[@meda04]

very easy to understand thank you

[@shelleylauritsen4169]

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]

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.

[@juanpablotorresdelacuadra9856]

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 =).

[@waliul280]

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).

[@rustyshackleford054]

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?

[@rosakuhn5274]

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

[@sciencenerd7639]

great video, thanks

[@Broccoli821]

Great explanation!

[@aufa2119]

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

[@snapple5950]

Also that Antelope be looking like Rudolph ngl

[@kathyyszn]

this helped a lot, thanks!

[@autumnd.2990]

Thank you. God is good.

[@Dr.IanPlect]

your god is mythology

[@katherinemcferrin6446]

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

[@Dr.IanPlect]

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

[@Lowzenza4]

What program do you use to do this?

[@siffo10]

Lots! One popular one is MEGA

[@dtrcs9518]

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

[@Jactos1691]

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

[@RandomActs0624]

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]

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]

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.

[@anxne2012]

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

[@aditivasmatkar6874]

Thank you Sal for making such helpful videos

[@harv029]

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

[@Dr.IanPlect]

eagle

[@melisabuken7744]

Thank you so much!!!

[@IchsanulIqbal-yv2ip]

love it

[@nikkiandress2530]

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

[@beautyblueable]

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

[@zoemorley3617]

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

[@burnsloads]

Yeah, well, ur gay.

[@sniperzBAK]

They show the same information...

[@rosakuhn5274]

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]

@@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.

[@omgchocolate4857]

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?

[@tiffanynorris1370]

More of this!!!! Loved it.

[@aidenmohrmann1850]

Thanks so much for your videos

[@TomWinkler-mz9yp]

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]

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.

[@sacul1291]

1:19

[@japanesereadingandwriting]

👍

[@MsChantae]

Thanks!

[@trenttwoider9346]

Another wonderful video

[@user-nn3bp8fy4e]

Watching this 1 hour before test🙋‍♂️

[@70snostalgia]

Thanks.

[@BrendanMcClelland]

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

[@JenDominance_Occupy]

this great

[@ollieanabella264]

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

[@Dr.IanPlect]

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

[@JungleJargon]

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

[@justinspearlord]

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

[@jeanettequintero2313]

Very helpful.

[@trishamedeiros1459]

I love you, man.

[@outlander271]

Ockham’s razor.

[@Maryam-kg7vp]

prisomny : is the simplest explanation of photogenic tree ??

[@Dr.IanPlect]

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

[@silverfoot6079]

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]

Lizards are NOT descendants of dinosaurs.

[@nothanks3724]

yay thank you!

[@Katiekazoo806]

Can there be another way to draw the phylogenetic tree?

[@Goldblasterblaze]

Yes

[@SamStarbucker]

I can finally breathe!!!

[@km2052]

awesome

[@d34thw4tch6]

I thought this was a cladogram

[@mikelombard21]

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.

[@thegoodfellas9746]

NOICE

[@BrendanMcClelland]

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

[@Emeka3]

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

[@sara-zb1ye]

online school tings

[@natashanajam3499]

why dis vid got no views? WTF youtube problem ?

[@edgarvillalba4234]

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

[@rudjard18]

luv u

[@senoritaAj]

Bruh

[@krishnan-resurrection714]

Trans and natural . . . . .😉😉😉

[@DAVIDPETERS12C]

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]

a point of obfuscation by an oxygen thief

[@DAVIDPETERS12C]

@@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. : )

[@rudra7615]

So lost bro

[@lymbopurgatum1235]

:3

[@samtalley6689]

This guy's swallowing gets on my nerves

[@vesuvandoppelganger]

Phylogenetic trees: Lines drawn between separately created species.

[@spatrk6634]

then creator is deceptive. making it look like all species are related.

[@bramaditya5499]

you are very fast in explaining, and didn't have a clear voice.