Hey.  So, this video lecture is 
about the two selections from Charles Darwin 
I asked you guys to read for this week.  
Um, so, that would be this excerpt from 
Chapter 3 of The Origin of Species entitled, "Struggle for Existence" 
and the selection from the Descent of Man 
entitled "Natural Selection and Sexual Selection."  
Darwin was probably the most important
or at least perceived to be the 
most important scientist of the Victorian era.  
He was definitely the preeminent naturalist.  
And, one of the things that Darwin does 
that is really, I mean, so, 
he gives us the theory of evolution.  
And this is important.  
But, the thing that Darwin does 
that is crucial for science is he regularizes science.  
Darwin's scientific technique is 
to observe natural phenomenon, 
observe a wide variety of natural phenomenon 
and attempt to draw conclusions 
based on his observations.  
And, this becomes the foundation of 
much modern science is this idea 
that we can understand the world around 
us through observations and through 
interpretation of the natural phenomenon that we observe.  
And Darwin really makes this sort of the main scientific technique.  
So, we have here a couple of his most important, specific ideas.  
Many of which continue actually to be ill-understood today 
because we sort of translate them into popular language, 
popular ideas, and then get them wrong.  
So, for instance, this theory of the struggle for existence, 
this idea of the survival of the fittest is something that we often misuse, 
or misunderstand when sort of popularly talking about it 
because what Darwin is talking about here 
is an incredibly complex series of processes within a community.  
Now, we often, I think, talk about the survival of the fittest 
as one creature is dominant, one person is dominant, whatever it is.  
And, so, when we talk about this as sort of a social metaphor, 
or an economic metaphor, or things like this, 
we are often sort of saying that you have to be ruthless, 
you have to really go for what you want, and things like this.  
That is not what Darwin is saying.  
That's not what the "struggle for existence" means.  
The struggle for existence for Darwin is located 
within ecosystems rather than, 
sort of, "ecoindividualism," or "ecoorganisms."
This is a sort of complex coexistence.  
And, he says this here at the top of 1562, he says, 
"I use this term (that's the "struggle for existence")
in a large and metaphorical sense,
including the dependence of one being on another,  
and including, which is more important, 
not only the life of the individual."  
So, this is the idea here, is that "survival of the fittest,"
the struggle for existence is about working together,
working within a community, 
and working within an ecosystem, 
that is a system, with a set of components, 
a set of elements for mutual survival.  
This is not, "I am going to get mine.  
I am out for myself" kind of situation.  
This is about understanding organisms 
within the context of other organisms, and sort of working together.  
And, he says this, he's got this section on 1563, 
where he is talking about the dependence of 
different kinds of species on one another.  
Ultimately, he comes to this conclusion.  
He is talking largely about flowers, initially.  
He says, "Hence we may infer as highly probable 
that if the whole genus of bumblebees became extinct 
or very rare in England, the Heart Season Red Clover 
would become very rare or wholly disappear."  
Actually, one of the big scientific crises 
right now is that massive amounts of bees 
are dying out and it is almost certainly 
going to have a major effect on ecosystems.  
[Chuckles.] Darwin is saying it here in the mid-Victorian period.  
But he goes beyond this.  
This is not just bees and flowers.  
Rather, we've got mice who destroy bees’ nests, 
and then cats who destroy mice.  
So, he says at the bottom of this paragraph on 1563, 
"Hence it is quite certain, or it is quite credible 
that the presence of a feline animal in large numbers 
in a district may determine through the intervention 
first of mice and then of bees the frequency 
of certain flowers in that district."  
So, this is a system.  
This is not a case where sort of individuals 
are the primary component here, 
or personal acquirement of resources is paramount, 
although personal acquirement of resources for Darwin is important.  
What matters here is ultimately that we understand nature, 
existence and our experience within ecosystems as systems.  
So, you kill the cats in the neighborhood,  
by extension, that affects the flower population.  
This is the way that things work according to Darwin.  
So, the other sort-of big component of Darwin's theory is evolution, 
and this is what he is most known for, 
and this is what he is most, sort of, important for, 
perhaps, in sort of scientific history, 
which I don't know a tremendous amount about.  
But, he says here, 1569, 
this is really sort of the thesis of the natural and sexual selection idea is that, 
"The main conclusion arrived at in this work 
and now held by many naturalists who are well 
competent to form sound judgment is that man 
is descended from some less highly organized form."  
So, he gives us some evidence of, 
he gives some evidence of the fact that 
humanity has derived from lower forms of life.  
"Lower forms of life" is now a problematic term
in the sciences, but this is the way that the Victorians thought of it.  
So, 1570, this sort of central, lengthy paragraph here, 
he gives us this sense that humans have evolved 
from a sort of advanced primate or ape, 
who was evolved from a basic monkey, 
who was evolved from sort of unknown marsupial, 
who is evolved from some reptile or amphibian, 
who evolved from some sort of aquatic animal 
with no gender, skeletal system, and with sort of, 
without fully-developed organ systems: brain, heart, lungs, whatever it is.  
And then, we can go sort of farther back than that now 
because we know more about early biology than Darwin did.  
We can talk about how this sort of primeval organism, 
sort of "jelly fish creature" [chuckles]
that Darwin imagines evolves from some single-cell organisms 
and things like this.  
And so, so, we've got this chain of descent here,  
what Darwin would call "Chain of Descent."  
And the reason that this happens according to Darwin, 
the reason that we have different species 
and different evolutionary tracts 
and things like this is because specific characteristics 
are identified as desirable, 
and these are reproduced through sexual selection.  
So, over hundreds, thousands, billions of generations of creatures, 
we get different characteristics 
of them as different traits: 
whether that is aesthetic traits like the most beautiful plumage, 
or whether that is survival traits like large teeth, 
thicker skin, better muscle structure, whatever it is.  
As these things get, 
as creatures that have these particular preferable traits 
make more, and creatures without those preferable traits make less, 
we have the reproduction of those traits.  
And Darwin says here on 1572, 
basically that all elements of life 
can be tied to sexual development and selection.  
He says, "He who admits the principle of sexual selection will 
be lead to the remarkable conclusion that the cerebral system
not only regulates most of the existing functions of the body 
but has indirectly influences the progressive development 
of various bodily structures and of certain mental qualities: 
courage, pertinacity, perseverance, strength 
and size of body, weapons of all kinds, 
musical organs both vocal and instrumental, 
bright colors, stripes and marks, 
and ornamental appendages 
have all been indirectly gained by the one sex or the other, 
through the influence of love and jealousy, 
through the appreciation of the beautiful and sound, 
color or form, and through the exertion of a choice.  
And these systems of the mind manifestly depend 
on the development of the cerebral system."  
In other words, our unconscious desire, 
the way that we choose mates, in theory, at least, 
leads to the perpetuation or extinction of certain traits.  
This is the really of sexual selection.  
This is the foundation of the theory of evolution, 
and it is upon this basis, as Darwin argues 
that humanity evolved from the apes, basically.  
I mean, from a slightly different form of life.  
I say "different" because I think that it is problematic 
to sort of hierarchize forms of life, and contemporary "ecocritcs," 
people who study literature and culture in relation to the environment, 
I think would probably agree with that point.  
Darwin is much more willing to hierarchize 
higher and lower orders of life, but I am going to say "different."    
But, then, I think ultimately the sort of interesting end point here, 
the last sentence in this section 
on natural and sexual selection is really interesting.  
This is 1573, Darwin says: "Man still bears in his bodily frame 
the indelible stamp of his lowly origin."  
I think that is actually a really cool idea.  
It destabilizes our human egotism,
the sort of sense that we have of being the greatest animal, 
the pinnacle of animals.  
Or, this sense that we have of being separate from nature.  
Being separate from other forms of life.  
That human beings are inherently different and special.  
This idea that no matter how sophisticated our culture, 
no matter how well established we are, 
no matter how many opposable thumbs we grow, 
we will always have in us, in our physical bodies, the remnants,
the echoes of that first single cell organism to experience life on this planet.  
