Intro Evolution

WELCOME TO EVOLUTION

DR. GRANADOS-CIFUENTES FIU - PCB4674

Sorry that the instrumental audio doesn't work on some mobile devices :'(

Why, if our body has such an exquisite design,

we have flaws that make us vulnerable to disease?

If our immune system can recognize a million foreign proteins…

why can we get COVID-19?

As a matter of fact,

why does SARS-CoV2 affect us? Isn't it a bat virus, anyways?

And, how come we have gone through the original strain and then other variants, like the new, current one, XFG?

Like, why are there so many variants?

If evolution by natural selection can shape sophisticated structures like the eye, heart, and brain…

why hasn’t it prevented nearsightedness, heart attacks, and Alzheimer’s disease?

As in, why does myopia exist?

Wouldn't it be eliminated as it would be too late to recognize the lion that was hunting you?

The lion would be like "hmm, you were supposed to run a long time ago, buddy"

And yet, myopia affects ¼ of the US population

We know high fat diet can cause heart attack…

why do we crave high-fat food?

Why do we crave these????

https://www.goya.com/en/recipes/colombian-beef-and-pork-empanadas

https://www.colombia.com/gastronomia/asi-sabe-colombia/amasijos/sdi140/16946/arepa-de-huevo

We know sun exposure causes skin cancer…

why do we crave being in the sun?

https://medium.com/ucsf-magazine/staying-safe-in-the-sun-2eaa9c6f0b39

If there is a natural mutation that makes people resistant to HIV…

why is there still HIV?

We know why we get specific diseases, but why do diseases exist at all?

The answer to these questions is not that natural selection is not strong enough

Plus, I could add similar examples from across the three domains of life, not limited to humans… or even eukaryotes

So, how do we answer these questions?

In past semesters (or perhaps the current semester), you took these classes to understand about the diseases themselves…

• Anatomy
• Physiology
• Genetics
• Cell bio
• Ecology
• Immunology

And what do these classes answer…

• Anatomy: what are the names of the structures
• Physiology: how things function/work
• Genetics: what are genes; how do genes code for structures
• Cell bio: how cells work and communicate with one another and the environment
• Ecology: how organisms interact with one another and with the environment
• Immunology: how does the immune system work

See the words in bold purple?

• Anatomy: what are the names of the structures
• Physiology: how things function/work
• Genetics: what are genes; how do genes code for structures
• Cell bio: how cells work and communicate with one another and the environment
• Ecology: how organisms interact with one another and with the environment
• Immunology: how does the immune system work

In this class, we won't answer "what" or "how"

We will answer

Why?

Also, important to understand Evolution...

is to clear

Misconceptions

Correcting misconceptions:

• Evolution is not about the origin of life
• Evolution is not a random process
• Evolution is not a progress process resulting in better organisms
• Evolution is not necessarily slow

Also...

• Natural Selection is not the survival of the fittest

And for sure

• We (humans) do not come from monkeys

We will see

• Out of the five processes, there is only one random process that leads to evolution
• Evolution can happen fast (sometimes in a day)
• An individual organism cannot evolve
• Natural selection is the survival of the fit enough
• Humans are still evolving

We will answer

Why?

“Nothing in biology makes sense except in the light of Evolution”Theodosius Dobzhansky