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This right here is a picture of Carl Linnaeus,
and I'm sure I'm mispronouncing the word.
And he's a Swedish gentleman who lived in the 1700's.
And he's known as the Father of Modern Taxonomy.
And the word taxonomy,
if you just split it up into it's original root,
it really is the science of really classifying things.
But when people talk about taxonomy,
in this particular in Carl Linnaeus' case,
they're talking about the classification of living things.
So, classifying... classifying, organisms.
And his real innovation, before he came about,
people realized that you had species of animals
that lions had certain properties that made them all lions,
and they could interbreed and things like that
monkey or chimpanzees would all interbreed
and that would be a separate species
and that polar bears were a separate species,
and that humans were a separate species.
But what he really brought to the table, is he decided,
well "Let me just not just group animals into species,
maybe I can group species into, into other categories
and that's where we get the genus from...
You group similar species into a genus.
And then he went even beyond that,
because even the idea of grouping things into a genus
dated back to the Ancient Greeks.
He said, "Well, why don't I group similar genuses together,
into orders, orders together into classes,
and then classes together into kingdoms.
So, really, what he did is, he said,
Well, maybe I can classify, I can create a tree.
I can create a tree of life.
I can create a structure so we can really see
how far apart any two organisms are.
And that's really why he's the Father of Modern Taxonomy.
And he did not have many tools.
All he could do was look at the powers,
his powers of observation.
He said: OK, those kinds of animals,
they have fur, or they reproduce in this way,
or they lay eggs, or they don't lay eggs,
or they have spinal columns,
or they don't have spinal columns.
So that's the best that he could do,
when he did his taxonomy.
But since then, there's obviously been tons of innovations
and how we perceive animals
or the natural world, and our tools for studying them.
So one thing that he did not know about is evolution.
This idea of common ancestry
and between our understandings of evolution
and our ability to look back at the fossil record,
that helps us get more precise at figuring out
which animals are related to which.
We can see: do they have a common ancestor,
more recent, or further back?
And what even Charles Darwin didn't have,
which we now use as a tool in taxonomy,
is the genetic evidence.
So now we don't even have to rely on the fossil record,
we can look at the DNA of two species that exist today
and see how similar is the DNA,
and that tells us how recently they branched apart
if we were able to find it in the fossil record
or how recently in the past
did these two species become two different species.
Now with that said, I do want to make this clear.
This is something, you know, I always have a little bit
It was fuzzy to me the first time I was exploring the idea of taxonomy.
It's that taxonomy is as much an art as it's a science.
Today, even to these days people are debating about
the best way to classify things.
And what you're pay attention to
and DNA has been the best tool so far
in giving us a more systematic, a more analytic way
of deciding how close two animals are,
but to a large degree a lot of these categories.
Deciding where to divide along
kingdom, phylum, class, order, family, tribe
these're somewhat arbitrary
these're just based on early taxonomists, including Carl Linnaeus
and saying "Oh this looks like a grouping right over here."
But they could have grouped on a broader level or at a deeper level
so this things right over here are somewhat arbitrary. Aaah...
A more analytic way is just to see
how much DNA you have in common
and then you just use that as a measure of
how far apart two animals are.
Or really I should say two species are,
because this taxonomy doesn't know
it doesn't apply just to animals,
it applies to plants and bacteria,
and Archaea and all sorts of things,
so it's actually a broader thing that just animals.
Now with that out of the way
what I'd thought would be fun
just so that we could really get a sense of
where modern taxonomy is,
where the field that was essentially fathered by Carl Linnaeus,
where it is now?
how we,... And use that to figure out
where we humans fit into the big picture.
And obviously I'm drawing
just a small fraction of the universe of the organisms
that we even know about right now,
but at least it frames the picture
in terms of something we understand,
in particular: us, in particular humans.
Now our species, we call ourselves humans,
but we are really *** sapiens
and the sapiens is the species part
and then *** is the genus.
What I'm doing right over here is I'm saying:
Well, if *** is the genus,
what other species were inside of ***?
and the reality is, or as least as far as we know,
there are no living species inside of ***
that we've probably killed them all of
or did or maybe we interbred with them somehow.
which might have argued that
maybe they weren't different species,
but more likely they were competing in the same ecosystems,
and they became endangered species very quickly
when they competed with our ancestors,
but the most recent other species within the genus
that we know about are the Neanderthals
and the formal word, the formal, the formal term
for their species is Neanderthalensis.
Now if we go further up the tree of life, further up the taxonomy,
and you'll sometimes see tribe dimension, sometimes you won't,
and we tend to get a little more granular
the closer we get to humans
when we go further away in the tree of life
we get a little bit less granular sometimes,
but that's not always the case, as well.
You go a little bit further up and you get to Hominini,
and I'm sure I am mispronouncing some of this, as well,
but another species that is in Hominini that is not in ***,
and I'm definitely not listing all of them
and that's why I'm showing all of these other branches,
all of these other branches over here,
is what we call the common chimpanzee
and their species name is, their genus is Pan
and their species is Troglodytes.
So you'd refer to them as Pan troglodytes.
And that's also another convention
that Carl Linnaeus came up with,
is that you refer to a particular species by its genus
and then its species, and you capitalize the genus
and you lower-case the species.
We are *** sapiens, this is *** neanderthalensis,
this is Pan troglodytes,
or often referred to as chimpanzees.
Now, if you go up one higher level of broadness
on this tree of life, you then get to the family
and we are in the family Hominidae, Hominidae
and I'm sure I'm mispronouncing it once again.
But just to give you an example,
so everything I listed so far,
everything I've talked about so far are within this family.
And to show you an animal that is not in this family
you just have to look at the gorilla.
And you could call it the Gorillini, the Gorillini
Gorillini gorilla, or G. gorilla,
that's its actual species name.
And this family right over here
sometimes the common term is the great apes,
the great apes.
Now you go one further level, and this is;
the whole reason why I'm doing this,
and I am not by any means,
am I being exhaustive about the other species
that are in that family but that are not in our tribe,
I'm just trying to get a picture of,
as we get further and further out,
as we get further out of our tribe, our family, our order,
we're getting to things where the common ancestor with human
goes further and further back in time,
the genetic similarities become more and more different,
and even just the physical differences
if we look at it in a very superficial level,
become more, and more, and more different.
So you get to even a broader category,
this is where you get to the primates
and this is probably something that
you might be somewhat familiar with.
And the term primates is general,
these animals that look like
they either live in trees or rain forests,
or they're descendant of things that live in trees
or they have these things that they can grasp things with.
They're good at climbing broadly, not all of them are.
Humans are probably the worst primates
when it comes to climbing, or one of the worst.
But that's the general classification that we...
that's what we generally think of
when we think of a primates.
And if we think of a primate that is not a great ape,
you just have to think of a baboon.
So this right here is a baboon.
It is a primate, but it is not a great ape.
It is probably descendant.
Some baboons actually don't live in trees,
but all of them are probably descendant
from things that first live in trees and
that's why their hands and their feet look the way they do.
Now you get into an even broader level of classification.
You get to the mammals, and once again,
probably something you're used to thinking about,
mammals are air-breathing animals.
They tend to have fur or hair.
They tend to provide some form of milk for their young.
They have active memory glands.
There're other things we can talk about what makes mammals.
I am not going into the rigorous definition.
But just to give you an example of a mammal that is not a primate,
I can show you a polar bear right over here.
This is a mammal, mammal that is not a primate.
I can do other thing. I can show you a tiger
or I can show you a giraffe or a horse.
By no stretch of the imagination, am I being comprehensive.
Let's keep getting broader. Now let's go to the class.
Or we are already at the class Mammalia.
Now let's go to the Phylum.
And Phylum...we are humans.
All mammals we are in the Phylum Chordates.
And Chordates we are actually in the sub Phylum,
which I didn't write here vertebrate,
which means we have a vertebra.
We have a spinal column with a spinal chordate.
Chordates are a little more general.
Chordate is a Phylum where kind of the arrangement
where the mouth is, where the digestive organs,
where the *** is, where the spinal column is,
where the brains, where the eyes, where the mouth.
They are kind of all in the same place.
If you think about it, everything I listed here,
kind of has the same general structure.
You have a spinal column.
You have a brain.
You have a mouth.
And the mouth leads to some type of digestive column.
In the end of it, you have an *** over there.
You have eyes in front of the brain.
So this is the general way.
I am not being very rigorous here.
It's how you describe a Chordate.
To show a Chordate that is not a mammal,
you just have to think about fish or sharks.
So this right over here,
this right over here is a non mammal Chordate.
This is a great white shark over here.
Let's go even broader.
You'll see, now we are getting to things
that are very very not human like.
So you go one step broader.
Now we are at Animalia, the kingdom of animals.
This is the broadest definition
or the broadest category that Carl Linnaeus thought about.
Actually he did go into trees as well.
When you think about kingdom of animals,
you think of things that aren't Chordates.
You start going into things like insects
You start going into things like jellyfish.
If you go even broader,
now we are talking about the domain.
You go into Eukarya.
So these are all organisms that have cells.
Inside those cells, they have complex structures.
So if you are Eukarya,
you have cells with complex structures.
If you are Prokarya,
you don't have complex structures inside your cells.
But other Eukarya that are not animals,
include things like plants.
Obviously I am giving no justice
to this whole branch of the tree of life.
It can be just as rich
or richer than everything I have drawn over here.
This is just a small fraction of the entire tree of life.
Let's go even broader than that.
So if you go even broader than that,
You say what's a kind of life form that isn't Eukarya?
That wouldn't have these more complex cell structures,
that is, the mitochondria in the cells, the cell nucleus-es.
Then you just have to think about something like bacteria.
If you want to go even broader,
there are things like viruses that
you can even debate whether they really even are life,
because they are dependent on other life forms
for their actual reproduction.
But they do have genetic materials like everything else.
That to me is kind of a mind blowing idea.
As different as a plant is,
look at house plants that are in your house right now,
or the tree when you walk home,
or bacteria or this jellyfish,
there is the commonality that we all have DNA.
That DNA for the most part
replicates in a very very very similar way.
So it's actually crazy that we are actually even all related.
We even do have a common ancestor,
or some of these things.
That even begs the question:
what are about things like viruses?
Anyway I'll leave you here.
I really just want to let you know that
make sure you realize that
it's definitely worth studying,
because we understand
where we fit in the universe of living things.
But I also want to let you know that
it is a little bit of an art on where you decide
where to make these classifications,
where you decide to focus on,
what you want to focus on,
you know, what properties,
how they reproduce
or how they feed their their young
or can they move around
or what they breed whatever, things like that.
Anyway I let you go there.