WEBVTT

00:00:32.435 --> 00:00:34.273
Wow! It's so great to be here!

00:00:34.273 --> 00:00:36.722
I'm so happy to see you guys.

00:00:36.722 --> 00:00:40.638
Arguably, one of the most disruptive 
events in the history of the planet

00:00:40.638 --> 00:00:42.848
has got to be the rise
of the animal kingdom.

00:00:42.848 --> 00:00:44.181
Definitely.

00:00:44.181 --> 00:00:47.222
I mean, here is Earth, simmering along, 
minding its own, single-cell business

00:00:47.222 --> 00:00:50.555
for nearly four billion years,
and some group of restless cells

00:00:50.555 --> 00:00:54.191
comes together and decides 
to become multi-cellular metazoa and well...

00:00:54.191 --> 00:00:57.328
the neighborhood's 
never been the same since, has it?

00:00:57.328 --> 00:01:00.331
And we have a remarkable 
diversity of animals

00:01:00.331 --> 00:01:02.635
with whom we share the planet, don't we?

00:01:02.635 --> 00:01:05.972
Millions of species swimming, 
scurrying, slipping around,

00:01:05.972 --> 00:01:08.773
seemingly endless forms,
most beautiful.

00:01:08.773 --> 00:01:10.803
How do you make sense of it all?

00:01:10.803 --> 00:01:15.245
Well, it may just help to know 
that 99% of all animal life

00:01:15.245 --> 00:01:18.303
fall into just eight major groups.

00:01:18.303 --> 00:01:20.972
Eight body plans.

00:01:20.972 --> 00:01:23.120
Scientists call these "phyla".

00:01:23.120 --> 00:01:27.359
And if you know these eight plans,
you've got an incredible grasp

00:01:27.359 --> 00:01:31.376
of the constraints and freedoms 
of the animal world.

00:01:31.376 --> 00:01:33.832
And there's something special
about these eight phyla.

00:01:33.832 --> 00:01:38.209
While species go extinct every day,
these phyla have prevailed and persisted

00:01:38.209 --> 00:01:41.505
for over 550 million years.

00:01:41.505 --> 00:01:44.174
Every mass extinction 
the planet has mustered,

00:01:44.174 --> 00:01:46.156
they've managed to make it through.

00:01:46.156 --> 00:01:48.405
So who are these amazing methuselahs?

00:01:48.405 --> 00:01:51.321
Let's look at plan 1: the sponges.

00:01:51.321 --> 00:01:54.018
These are Earth's first 
true blue animals.

00:01:54.018 --> 00:01:57.209
They scripted that vital language
for single cells to work together

00:01:57.209 --> 00:02:00.929
with other cells for a common cause,
in this case, pumping.

00:02:00.929 --> 00:02:03.126
So hail Mother Sponge!

00:02:03.126 --> 00:02:05.457
It sucks, it pumps, 
it's a mother of us all.

00:02:05.457 --> 00:02:08.875
And you know, some of us have a problem
being descendants from apes. Well...

00:02:08.875 --> 00:02:13.293
So, plan number 2: the cnidarians:
anemones, jellies and corals.

00:02:13.293 --> 00:02:17.708
These were the first guys to put muscle 
and nerve together into a body plan,

00:02:17.708 --> 00:02:20.245
and with that, we get animal behavior.

00:02:20.245 --> 00:02:23.626
They're characterized by a round body, 
radially symmetric,

00:02:23.626 --> 00:02:25.983
and little stinging cells called "cnidae".

00:02:25.983 --> 00:02:27.958
If any of you have been 
stung by a jellyfish,

00:02:27.958 --> 00:02:29.927
you know what I mean, 
they pack a punch.

00:02:29.927 --> 00:02:32.856
So these were the first guys
to coin animal behavior.

00:02:32.856 --> 00:02:36.931
Okay, our next body plan –
look at those little anemones –

00:02:36.931 --> 00:02:39.958
– are the platyhelminthes.
Very contemptuous phylum,

00:02:39.958 --> 00:02:42.167
many biologists don't feel 
it's a true phylum,

00:02:42.167 --> 00:02:44.435
but comprised of many different phyla,

00:02:44.435 --> 00:02:50.177
and so right now the animal tree
is being shaken right at its roots.

00:02:50.177 --> 00:02:54.912
But what you need to take home
from this representative body plan is that,

00:02:54.912 --> 00:02:58.708
here we see the first representation 
of a left-right symmetry.

00:02:58.708 --> 00:03:01.876
Bilateral symmetry, 
which all complex animals have.

00:03:01.876 --> 00:03:05.782
And a concentration of sense organs 
right at one part of the body.

00:03:05.782 --> 00:03:07.485
The makings of a head,

00:03:07.485 --> 00:03:09.651
and with a head you can have 
directed animal behavior,

00:03:09.651 --> 00:03:11.519
and hunting.

00:03:11.519 --> 00:03:14.323
This is also where we think 
animals first started

00:03:14.323 --> 00:03:18.950
to get a threshold level 
of genetic complexity

00:03:18.950 --> 00:03:21.831
and pole body patterning genes 
called Hox genes.

00:03:21.831 --> 00:03:24.701
And that, coupled with the right 
environmental conditions,

00:03:24.701 --> 00:03:27.069
and serendipitous fossilization,

00:03:27.069 --> 00:03:30.866
catalyzed its incredible 
radiation of animal diversity

00:03:30.866 --> 00:03:33.577
best known from the Cambrian explosion.

00:03:33.577 --> 00:03:37.479
Also in this group is, we think,
the appearance of the first penis.

00:03:37.479 --> 00:03:40.363
And as I've raised that subject,

00:03:40.363 --> 00:03:44.283
I have to talk about one modern 
representative, the turbellarians.

00:03:44.283 --> 00:03:48.658
These guys have not one, 
but two penises that are hypodermic.

00:03:48.658 --> 00:03:50.492
And they joust with them.

00:03:50.492 --> 00:03:53.332
And the first one to jab its sperm 
into the other gets to be the boy,

00:03:53.332 --> 00:03:56.066
while the jab-ee gets to be the girl.

00:03:56.066 --> 00:03:59.431
And this remarkable behavior
is aptly called penis-fencing.

00:03:59.431 --> 00:04:01.264
Go figure.
(Laughter)

00:04:01.264 --> 00:04:03.874
OK, moving on to the fourth: 
we have the annelids.

00:04:03.874 --> 00:04:09.846
These animals have 
a body cavity called the coelom.

00:04:09.846 --> 00:04:14.181
And they're known by having these 
little rings running down their bodies.

00:04:14.181 --> 00:04:16.752
What these guys brought 
into the animal world

00:04:16.752 --> 00:04:21.656
was the ability to penetrate into the soil,
bring oxygen in and release carbon dioxide.

00:04:21.656 --> 00:04:24.013
And releasing carbon dioxide
actually helped

00:04:24.013 --> 00:04:26.845
to heat the planet up and make it 
more livable for other life.

00:04:26.845 --> 00:04:29.513
Now we've got too much CO2, 
but at the time,

00:04:29.513 --> 00:04:32.304
this was really an important thing
that the annelids brought to the planet –

00:04:32.304 --> 00:04:34.598
Bioturbation. Okay.

00:04:34.598 --> 00:04:38.372
Our next plan we've got are the mollusks.
Amazing phylum.

00:04:38.372 --> 00:04:41.420
Tiny little shelled animals to giant squid.

00:04:41.420 --> 00:04:44.263
All characterized by a single slimy foot.

00:04:44.263 --> 00:04:47.762
And what the mollusks show us, 
most of them are shelled.

00:04:47.762 --> 00:04:52.585
And we can see in the mollusk phylum 
is this arms race escalation,

00:04:52.585 --> 00:04:55.497
with shells becoming 
more increasingly complex

00:04:55.497 --> 00:05:00.140
in response to more complex predation 
from other phyla,

00:05:00.140 --> 00:05:03.224
so they kind of exemplify 
an arms race escalation,

00:05:03.224 --> 00:05:06.214
with some of them actually 
doing away with the shell completely,

00:05:06.214 --> 00:05:11.223
trading it for smarts and psychedelic skin 
that we see in the squid and the octopus.

00:05:11.223 --> 00:05:13.992
And these are the guys
who can change color

00:05:13.992 --> 00:05:17.001
and texture of their skin
in split-seconds,

00:05:17.001 --> 00:05:19.891
the rockstars of the mollusk phylum.
Gotta love these guys. (Laughter)

00:05:19.891 --> 00:05:21.975
And they can even be bipedal!

00:05:21.975 --> 00:05:26.029
Okay, our next phylum are 
the echinoderms, the spiny-skinned guys.

00:05:26.029 --> 00:05:29.965
The sea stars, sea urchins,
and sea cucumbers.

00:05:29.965 --> 00:05:33.802
And they're characterized by 
an internal skeleton of little plates

00:05:33.802 --> 00:05:37.914
that can lock together with 
very little energy expenditure.

00:05:37.914 --> 00:05:40.916
And underneath are these tube feet 
that allow them to move

00:05:40.916 --> 00:05:43.278
and shuttle food to their central mouth.

00:05:43.278 --> 00:05:45.166
Now, these are a complex animal,

00:05:45.166 --> 00:05:47.614
but they decided to do away
with bilateral symmetry,

00:05:47.614 --> 00:05:49.916
they have a five-part symmetry.

00:05:49.916 --> 00:05:51.832
And they have no brain.

00:05:51.832 --> 00:05:57.584
And they seem like they don't do much, 
they just sit there on the sea floor.

00:05:57.584 --> 00:06:01.250
But you speed them up in timelapse and 
you see that they're incredibly industrious.

00:06:01.250 --> 00:06:05.083
And they actually comprise the bulk 
of the biomass in the deep sea environment.

00:06:05.083 --> 00:06:07.333
Very successful body plan.

00:06:07.333 --> 00:06:10.665
Our next one, the true rulers 
of the planet, the arthropods.

00:06:10.665 --> 00:06:15.477
Now, if you look at all the animals,
the arthropods comprise the bulk.

00:06:15.477 --> 00:06:18.145
Eighty percent are arthropods.

00:06:18.145 --> 00:06:23.951
If you added up the biomass of humans,
they are 300 times the biomass of all humans.

00:06:23.951 --> 00:06:26.498
And most of them are insects!

00:06:26.498 --> 00:06:31.083
Did you know that four out of five
animals have six legs?

00:06:31.083 --> 00:06:36.530
So, these are the first guys 
that walked out of the ocean

00:06:36.530 --> 00:06:38.503
and started to explore at land.

00:06:38.503 --> 00:06:40.750
They were the first ones 
that took to the skies.

00:06:40.750 --> 00:06:45.400
100 millions of years before the birds 
ever thought of doing such a thing.

00:06:45.400 --> 00:06:47.274
So, what is the secret to their success?

00:06:47.274 --> 00:06:50.217
How are they able to be in 
every environment imaginable?

00:06:50.217 --> 00:06:53.282
Well, it has something to do 
with that outside skeleton,

00:06:53.282 --> 00:06:54.916
their exoskeleton.

00:06:54.916 --> 00:06:56.999
And their diversity of appendages 
down their body,

00:06:56.999 --> 00:06:58.666
like a little Swiss army knife.

00:06:58.666 --> 00:07:01.167
They can have multiple antennae,
multiple legs, multiple wings,

00:07:01.167 --> 00:07:05.027
multiple reproductive organs,
it's just an amazing attribute

00:07:05.027 --> 00:07:09.636
that allows them to infiltrate 
every habitable space on the planet.

00:07:09.636 --> 00:07:13.135
And the last phylum, the chordates.

00:07:13.135 --> 00:07:17.104
This is, of course, where we originated 
over 550 million years ago.

00:07:17.104 --> 00:07:20.308
And it's characterized 
by having a spinal cord,

00:07:20.308 --> 00:07:23.944
right there you see in pink, 
that blossoms into a brain in vertebrates,

00:07:23.944 --> 00:07:26.581
and underneath a notochord,

00:07:26.581 --> 00:07:29.665
which turns into a bony spinal column 
in the vertebrates as well.

00:07:29.665 --> 00:07:32.888
And this is all the guys that 
make the silver screen all the time.

00:07:32.888 --> 00:07:37.627
The mammals, and the amphibians, 
and the reptiles, and of course, the fish.

00:07:37.627 --> 00:07:40.501
The bulk of the chordates are the fishes.

00:07:40.501 --> 00:07:43.131
And these are all the guys 
we know and love.

00:07:43.131 --> 00:07:47.350
And of course, the fish –

00:07:47.350 --> 00:07:50.830
that's one of my favorite fish, 
the mola mola.

00:07:50.830 --> 00:07:54.108
And it includes our kin, 
our land-loving hominids.

00:07:54.108 --> 00:07:56.166
These are my little ones.

00:07:56.166 --> 00:07:59.381
So that's the basic eight,

00:07:59.381 --> 00:08:06.054
and, I think, to recap,
why don't we do that with a song?

00:08:06.054 --> 00:08:09.725
Alright, you guys ready? Okay.

00:08:09.725 --> 00:08:12.228
And now, a song.

00:08:12.228 --> 00:08:16.031
The sponges started everything,
pumping up a storm,

00:08:16.031 --> 00:08:18.534
...among the ruckus, 
the rest of us was born.

00:08:18.534 --> 00:08:21.704
Cnidarians muscled up, 
mixed nerves into the potion,

00:08:21.704 --> 00:08:25.138
and with that quick addition
got us brand-new locomotion.

00:08:25.138 --> 00:08:28.545
The flattish worm-like hunters 
got a head and then some traction,

00:08:28.545 --> 00:08:31.916
and with some senses and a penis – 
Oooh! – scored some action.

00:08:31.916 --> 00:08:33.948
The shape of life, yeah.

00:08:33.948 --> 00:08:38.819
And here we have penis fencing 
in flagrante delicto.

00:08:38.819 --> 00:08:45.269
The shape of life, yeah...

00:08:45.269 --> 00:08:48.602
Now, being male and female,
that just works out great,

00:08:48.602 --> 00:08:52.434
anybody in the world
can double as your date.

00:08:52.434 --> 00:08:55.603
Then all hell broke loose 
and the other plans appeared.

00:08:55.603 --> 00:08:58.853
The Cambrian exploded, 
launched the world into high gear.

00:08:58.853 --> 00:09:02.352
The annelids took to the dirt 
and bioturbatin'.

00:09:02.352 --> 00:09:05.884
The mollusks took to fighting
and arms race escalating.

00:09:05.884 --> 00:09:08.925
Echinos said, "The heck with this,
we're better off instead

00:09:08.925 --> 00:09:12.735
taking life into the slow land,
lopping off that head."

00:09:12.735 --> 00:09:16.093
Arthros stepped onto the land 
and ruled, that ain't no mystery,

00:09:16.093 --> 00:09:19.426
till bonehead chordates followed 
and soon would rewrite history.

00:09:19.426 --> 00:09:22.153
The shape of life, yeah...

00:09:22.153 --> 00:09:24.675
Okay, very good!
(Applause)

00:09:30.873 --> 00:09:35.595
So why study these mostly 
slimy, spineless critters

00:09:35.595 --> 00:09:39.348
with whom we co-pilot spaceship Earth?

00:09:39.348 --> 00:09:41.328
Well, were it not for them, 


00:09:41.328 --> 00:09:44.554
none of us would be strutting and 
fretting our ten minutes upon this stage.

00:09:44.554 --> 00:09:47.690
It's the animal life and 
all the life that came before us

00:09:47.690 --> 00:09:51.227
and with whom we share this planet 
that not only set the stage,

00:09:51.227 --> 00:09:55.132
but created the very stage for all life 
to flourish in the future.

00:09:55.132 --> 00:09:58.348
And I can't put it any more eloquently 
than E. O. Wilson, who says:

00:09:58.348 --> 00:10:03.674
"Humanity is exalted, not because 
we are so far above every thing living,

00:10:03.674 --> 00:10:07.941
but because knowing them well
elevates the very concept of life."

00:10:07.941 --> 00:10:09.692
Thank you.

00:10:09.692 --> 00:10:13.692
(Applause)