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  • How would you like to be better than you are?

  • Suppose I said

  • that, with just a few changes in your genes,

  • you could get a better memory --

  • more precise,

  • more accurate and quicker.

  • Or maybe you'd like to be more fit, stronger,

  • with more stamina.

  • Would you like to be more attractive and self-confident?

  • How about living longer with good health?

  • Or perhaps you're one of those

  • who's always yearned for more creativity.

  • Which one would you like the most?

  • Which would you like, if you could have just one?

  • (Audience Member: Creativity.)

  • Creativity.

  • How many people would choose creativity?

  • Raise your hands. Let me see.

  • A few. Probably about as many as there are creative people here.

  • (Laughter) That's very good.

  • How many would opt for memory?

  • Quite a few more.

  • How about fitness?

  • A few less.

  • What about longevity?

  • Ah, the majority. That makes me feel very good as a doctor.

  • If you could have any one of these,

  • it would be a very different world.

  • Is it just imaginary?

  • Or, is it, perhaps, possible?

  • Evolution has been a perennial topic

  • here at the TED Conference,

  • but I want to give you today

  • one doctor's take on the subject.

  • The great 20th-century geneticist,

  • T.G. Dobzhansky,

  • who was also a communicant

  • in the Russian Orthodox Church,

  • once wrote an essay that he titled

  • "Nothing in Biology Makes Sense

  • Except in the Light of Evolution."

  • Now if you are one of those

  • who does not accept the evidence for biological evolution,

  • this would be a very good time to turn off your hearing aid,

  • take out your personal communications device --

  • I give you permission --

  • and perhaps take another look at Kathryn Schultz's book on being wrong,

  • because nothing in the rest of this talk

  • is going to make any sense whatsoever to you.

  • (Laughter)

  • But if you do accept

  • biological evolution,

  • consider this:

  • is it just about the past,

  • or is it about the future?

  • Does it apply to others,

  • or does it apply to us?

  • This is another look at the tree of life.

  • In this picture,

  • I've put a bush with a center branching out in all directions,

  • because if you look at the edges

  • of the tree of life,

  • every existing species

  • at the tips of those branches

  • has succeeded in evolutionary terms:

  • it has survived;

  • it has demonstrated a fitness

  • to its environment.

  • The human part of this branch,

  • way out on one end,

  • is, of course, the one that we are most interested in.

  • We branch off of a common ancestor

  • to modern chimpanzees

  • about six or eight million years ago.

  • In the interval,

  • there have been perhaps 20 or 25

  • different species of hominids.

  • Some have come and gone.

  • We have been here for about 130,000 years.

  • It may seem like we're quite remote

  • from other parts of this tree of life,

  • but actually, for the most part,

  • the basic machinery of our cells

  • is pretty much the same.

  • Do you realize that we can take advantage

  • and commandeer the machinery of a common bacterium

  • to produce the protein of human insulin

  • used to treat diabetics?

  • This is not like human insulin;

  • this is the same protein

  • that is chemically indistinguishable

  • from what comes out of your pancreas.

  • And speaking of bacteria,

  • do you realize that each of us carries in our gut

  • more bacteria

  • than there are cells in the rest of our body?

  • Maybe 10 times more.

  • I mean think of it,

  • when Antonio Damasio asks about your self-image,

  • do you think about the bacteria?

  • Our gut is a wonderfully hospitable environment

  • for those bacteria.

  • It's warm, it's dark, it's moist,

  • it's very cozy.

  • And you're going to provide all the nutrition that they could possibly want

  • with no effort on their part.

  • It's really like an Easy Street for bacteria,

  • with the occasional interruption

  • of the unintended forced rush to the exit.

  • But otherwise,

  • you are a wonderful environment for those bacteria,

  • just as they are essential to your life.

  • They help in the digestion of essential nutrients,

  • and they protect you against certain diseases.

  • But what will come in the future?

  • Are we at some kind of evolutionary equipoise

  • as a species?

  • Or, are we destined

  • to become something different --

  • something, perhaps, even better adapted

  • to the environment?

  • Now let's take a step back in time

  • to the Big Bang, 14 billion years ago --

  • the Earth, the solar system,

  • about four and a half billion years --

  • the first signs of proto-life,

  • maybe three to four billion years ago on Earth --

  • the first multi-celled organisms,

  • perhaps as much

  • as 800 or a billion years ago --

  • and then the human species,

  • finally emerging

  • in the last 130,000 years.

  • In this vast unfinished symphony of the universe,

  • life on Earth is like a brief measure;

  • the animal kingdom,

  • like a single measure;

  • and human life,

  • a small grace note.

  • That was us.

  • That also constitutes the entertainment portion of this talk,

  • so I hope you enjoyed it.

  • (Laughter)

  • Now when I was a freshman in college,

  • I took my first biology class.

  • I was fascinated

  • by the elegance and beauty of biology.

  • I became enamored of the power of evolution,

  • and I realized something very fundamental:

  • in most of the existence of life

  • in single-celled organisms,

  • each cell simply divides,

  • and all of the genetic energy of that cell

  • is carried on in both daughter cells.

  • But at the time multi-celled organisms come online,

  • things start to change.

  • Sexual reproduction enters the picture.

  • And very importantly,

  • with the introduction of sexual reproduction

  • that passes on the genome,

  • the rest of the body

  • becomes expendable.

  • In fact, you could say

  • that the inevitability of the death of our bodies

  • enters in evolutionary time

  • at the same moment

  • as sexual reproduction.

  • Now I have to confess,

  • when I was a college undergraduate,

  • I thought, okay, sex/death, sex/death, death for sex --

  • it seemed pretty reasonable at the time,

  • but with each passing year,

  • I've come to have increasing doubts.

  • I've come to understand the sentiments of George Burns,

  • who was performing still in Las Vegas

  • well into his 90s.

  • And one night, there's a knock at his hotel room door.

  • He answers the door.

  • Standing before him is a gorgeous, scantily clad showgirl.

  • She looks at him and says,

  • "I'm here for super sex."

  • "That's fine," says George, "I'll take the soup."

  • (Laughter)

  • I came to realize,

  • as a physician,

  • that I was working toward a goal

  • which was different from the goal of evolution --

  • not necessarily contradictory, just different.

  • I was trying to preserve the body.

  • I wanted to keep us healthy.

  • I wanted to restore health from disease.

  • I wanted us to live long and healthy lives.

  • Evolution is all about passing on the genome

  • to the next generation,

  • adapting and surviving

  • through generation after generation.

  • From an evolutionary point of view,

  • you and I are like the booster rockets

  • designed to send the genetic payload

  • into the next level of orbit

  • and then drop off into the sea.

  • I think we would all understand the sentiment that Woody Allen expressed

  • when he said, "I don't want to achieve immortality through my work.

  • I want to achieve it through not dying."

  • (Laughter)

  • Evolution does not necessarily

  • favor the longest-lived.

  • It doesn't necessarily favor the biggest

  • or the strongest or the fastest,

  • and not even the smartest.

  • Evolution favors

  • those creatures best adapted

  • to their environment.

  • That is the sole test

  • of survival and success.

  • At the bottom of the ocean,

  • bacteria that are thermophilic

  • and can survive at the steam vent heat

  • that would otherwise produce, if fish were there,

  • sous-vide cooked fish,

  • nevertheless, have managed

  • to make that a hospitable environment for them.

  • So what does this mean,

  • as we look back at what has happened in evolution,

  • and as we think about the place again

  • of humans in evolution,

  • and particularly as we look ahead

  • to the next phase,

  • I would say

  • that there are a number of possibilities.

  • The first is that we will not evolve.

  • We have reached

  • a kind of equipoise.

  • And the reasoning behind that would be,

  • first, we have, through medicine,

  • managed to preserve a lot of genes

  • that would otherwise be selected out

  • and be removed from the population.

  • And secondly, we as a species

  • have so configured our environment

  • that we have managed to make it adapt to us

  • as well as we adapt to it.

  • And by the way, we immigrate and circulate

  • and intermix so much

  • that you can't any longer

  • have the isolation that is necessary

  • for evolution to take place.

  • A second possibility

  • is that there will be evolution of the traditional kind,

  • natural, imposed by the forces of nature.

  • And the argument here would be

  • that the wheels of evolution grind slowly,

  • but they are inexorable.

  • And as far as isolation goes,

  • when we as a species

  • do colonize distant planets,

  • there will be the isolation and the environmental changes

  • that could produce evolution

  • in the natural way.

  • But there's a third possibility,

  • an enticing, intriguing and frightening possibility.

  • I call it neo-evolution --

  • the new evolution

  • that is not simply natural,

  • but guided and chosen

  • by us as individuals