How the La Brea Tar Pits Work

It's surprising that a few 12-feet-deep pools of asphalt have proven to be one of the most significant troves of Pleistocene fossils, but the La Brea Tar Pits, located in the heart of Los Angeles, are giving science a clear picture of a puzzling time.

Learn more about your ad-choices at https://www.iheartpodcastnetwork.com

See omnystudio.com/listener for privacy information.

Episode Transcript

Speaker 1 (00:01):
Welcome to you stuff you should know from house Stuff
Works dot com. Hey, and welcome to the podcast. I'm
Josh Clark, There's Charles W. Chuck Bryant, and Jerry's over
there making our lives difficult. And uh so that as
usual means it's time for stuff you should that's right. Yes,

(00:23):
how are you, my friend? I'm good? Good, yeah, well healthy,
feel a little tubby, but yeah, oh yeah, I'm okay.
That just means you've been living, right, that's my motto.
It's sugar cookies, yeah, which I like. Yeah, you gotta
have sugar cookies sometimes. So I leave for l A
in the morning, where the home of the Librarea tart pits.

(00:46):
I didn't realize that you were doing the intro or
should I call it Pueblo Dave nuestra senora la de
los Angeles. I want us, I think. So it's hard
to hear that los Angeles without thinking it really is. Yeah,
but yes, that was the original name of Los Angeles, Chuck,
did you know that before this? Yeah? I did not. Sure.

(01:07):
That's a mouthful. I can see why everybody just calls
it Los Angeles. Or if you're really hip l A, yeah,
or if you're a jackass city of angels. That's like
people do Hotlanta. Yeah, some people say that you can
get a magnet still, that says Hota. Yeah, well, no
one in it or from Atlanta says that. That's a

(01:29):
total outsider thing. You don't think they make Atlanta magnets
in Atlanta. Yeah, but they saw him at the airport,
you know, Atlanta people selling it. That's like saying Nevada
instead of Nevada. Is that really how it's supposed to
be pronounced Nevada? Yeah? Man, you don't hear everyone every
time they don't see those emails from angery Nevadas Nevadians.

(01:52):
After a while, they just kind of all become a blur. Yeah,
we get taken the dank for that. And I said,
you know what, everyone outside Nevada says, Nevada I hate
to break. Yeah, like everybody. And they say, you know what,
everyone outside of Atlanta says Hotlanta. I don't think they
say that. Some people do, but now I don't. I
don't hold the grudge against you. If you say it,
I just pretend you aren't there. Okay, you know, you

(02:12):
just ignore Hot Lanta. Uh So that was my intro.
That was a good one, man. I think you should
do one and people should vote. Oh here is mine, Chuck.
Have you ever been to Los Angeles? You used to
live there, didn't you. Yeah, and you've been to the
Break of tar Pits obviously a bunch of times. Surely
I've been on to you. And I went to LACMA. Yeah, yeah,

(02:35):
I had no idea. It was like right there, mid
Wiltshire Miracle Mile. It's like you you walk out the
back entrance into a Japanese garden at at the Los
Angeles County Museum of Art BLACKMA, and you just keep
walking a little further and all of a sudden there's
a huge masted on and then you go into the
museum that time forgot it was closed while we were there,

(02:57):
And I'm really sad, especially after reading this article. The
page museum is what it's called. Are they Did they
update it? I think they might have updated it. No, no, no,
I mean like it was closed for the day. Oh
like we spent all of our time in Lachmen and
then came out. It was close for the David mm hmmm.
I think they may have updated. I think they did
very recent since I left because when I went in

(03:17):
when I was living there in late two thousands or
late nineties, early two thousand's, it was delightfully old. Yeah,
well it was open in seventy seven. Yeah, it looked
pretty untouched, mechanical mastodon's inside that we're all like clunky
and oh no, I'm really we gotta go back. Yeah,
it's pretty neat the herky jerky masthodon. And they could

(03:38):
tell they were old. Yeah, not in the ways that
mastodons are supposed to be old. From the seventies. Yeah.
So no, I haven't been to the Page Museum, but
I have been to the tar pits themselves. And tar
pits actually is a misnomer. Yeah, they're actually they should
be called asphalt pits or bitumen pits because tar is

(04:00):
derived from coal and these pits are derived from petroleum. Yeah,
so that's there's the fact of the podcast. Sadly is
it is that the fact that the podcast, Yeah, the
oil crude oil steeps up through fissures in the Earth's
crust and then some of that evaporates, and that leaves
behind that tar asphalt asphalt. But let's go back even

(04:21):
further than that. These tar pits leabre of tar pits,
which are basically for anybody who hasn't been there, if
you're walking around the grounds of the tar pits, there's
just basically black ponds that look like they have oil
slicks on top of them. Then when you look a
little close, you're like, oh, it's all oil. Yeah. Every
once in a while there's a bubble coming up here
there quite a bit uh and um again there's like

(04:44):
a huge masted on coming out like a model coming
out of the out of the one of the pits.
It's pretty cool, well, not quite coming out, but trying
to write, he's never gonna come out. You never made
that played out as a film that he would make
it out right. Um. And that's the whole reason that
the tar pits are even um have fences and a

(05:06):
plastic masted on in the first place. Because many many
millions of years ago, Los Angeles was underwater. There's a
lot of aquatic life that lived and died in that area,
and uh went to the bottom, and over time we're
compressed into the fossil fuel petroleum fossil fuel. Yes, yeah,

(05:27):
And then as the ice age came and the waters
were seated and were locked into glaciers up north um
that land became drier and as a result, like you said,
that bit Chaman started coming up through fissures in the
ground and has been ever since. Those are the Librea
tar pits. That's right, and uh in those pits, we're

(05:47):
talking about the Pleistocene epoch, which is about two point
six million to eleven thousand, seven hundred years ago. And
the neat thing is is except for a handful, well
more than a handful, except for some of these huge
land mammals that they found, a lot of the animals
are the same as they are now. And this was

(06:08):
the last time we had major climate cooling, So studying
these fossils can like, we can learn more about our
climate from studying these things than I don't know what
I was halfway those sentence was like, wait a minute,
I don't know what part two is, but yeah, I
think you made the point. Yeah, but that's how they
You know, you can learn a lot from uh future

(06:29):
climates by studying past climates, right exactly, And that's one
of the things that they're doing now. There's kind of
a second wind that's going on the Libreo tar pits.
The first win came about what we should say, Um,
Since the LaBrea tar pits made their first debut about
forty tho years ago, it's been they've been successfully trapping
animals of all sorts and not just animals of plant

(06:50):
life too. Yea mostly carnivores though, yes, And there's a
reason that there's mostly carnivores. They figured it out because
there is a disproportionate amount of carnivores in the Librea
tar pits. Yeah, which is way more than there were
carnivores proportionately speaking during the Pleistocene epoch, specifically this last

(07:15):
year era. Um. And they they think they haven't figured
out why. Well, it makes total sense. Animal gets stuck
in tarpit, bigger animal comes along and wants to eat
that animal, it gets stuck in tarpit, and maybe even
a bigger animal wants to eat both of those it
gets stuck in tarpit. Yeah. Well, plus also a lot
of carnivores hunting packs. So if they're like, well, this

(07:38):
stupid mastodon can't get out of this black pond, I'm
going in after him. Let's all go in after him.
Everybody gets stuck pretty much it. Yeah, that's why there's
more carnivores. That's why they're just proportionately represented. Yeah, it's
actually I said he talking about the mastodon outside the
fake one. I believe it's if I remember correctly, a mama.

(07:59):
Oh yeah, there's babies, and there's babies like on the
shore and the mama is trapped and it's really kind
of sad, is what they picked there. But I guess
that was the realism of the place to see an
epoch these mommy goes hunting and doesn't come back. It's right,
it's like, yeah, and you can. I think I've told
this story before. I was shooting there once on a
TV commercial and I was far away from the uh

(08:23):
the large pools, and I was standing there and I
looked down and there was a little two foot diameter
pool of tar right by my feet. Yeah, I mean,
they're not all walled up and fenced off, and it
was bubbling. Uh you know what that is, by the way,
the it's methane, I guess, yeah, from bacteria they found out.
So that was only like five or six years ago

(08:44):
that they've learned that. And they discovered like two d
new kinds of bacteria that's neat petroleum loving bacteria. Yeah,
that's great, and that it's still burping even in these
tiny little puddles. Yeah, and they're the even the big
puddles are only about twelve ft deep. Yeah. It's just
like meat or something like that for our non Liberian friends. Yeah. Yeah, so, um,

(09:07):
the tar pits have been just trapping animals, like you said,
even there's lots of recent animals in it. They found.
They still find cattle bones. Rodney Dangerfield, Yeah, he was
found in there. Apparently there was a Los Angeles um
Police Department scuba diver that dove into the pits to
retrieve evidence for cold murder case and was successful apparently.

(09:29):
But he said, like I've dived all over the place
looking for evidence. He said, that was the craziest dive
I've ever made. He's scuba dived in the tar pit. Wow. Yeah.
And the article I read wasn't really um big on detail.
They wouldn't even say what evidence he was looking for.
It must be less dense as you go, because the

(09:51):
tar that I've seen it's like, I mean, it's like
road tards, so thick. I don't see how you can move.
I would think scuba diver gets trapped. I think it's
probably more dense towards the bottom, and if you're a
masted on, you're like, it's probably quick sandy, and this
guy was probably avoiding the bottom. Plus I'm sure there
are a lot of people like pulling him out. Yeah.
I think that bad Roblow movie they he did a

(10:12):
buried body in there. Yeah, I mean it's what was
what was that bad that influence bad influence bad behavior,
familiar bad something bad movie that's probably pretty bad. This
is before Rob Blow had his comeback. This is the
post sex stape years. Oh yeah, when he was just
trying to hang in there, trying to hang in there. Yeah,

(10:33):
we don't make it back row Blow. But they got
all kinds of like sabre tooth tigers and dire wolves
and like original original native horses to North America that
don't exist anymore. There used to be horses here. There
used to be camels, and they're not like the European
horses that everyone thinks their horses here. You're focusing on
the horses. There used to be camels here, I know.

(10:54):
And like you said, sabre tooth tigers they found about
um four thousand of those. The higher wolf they found
about two thousand dire wolves so far. Um and then uh,
they also found something called the American lion. This thing
was the coolest animal in North America ever. Right. They
got up to eight ft long four ft at the haunches. Um.

(11:19):
They weighed something like up to seven seventy five pounds,
which is three These are giant mantals. They were about
larger than an African lion. They were huge. If they
wanted you dead, you were dead. Not like these lions
these days. They're lazy. This American lion would have just

(11:39):
taken your head clean off and burt. All sorts of
flightless predator or flightless flying predators in the sky. Yeah, um,
they're in apparently. So far they found six hundred sixty species,
fifty nine mammal species, a hundred and thirty five bird species,
tons of everything from like mall asks to um. The

(12:01):
new bacteria you're talking about, the libre tarpets have been
so vital and providing a picture of um, the of
life during the late Paleozoic that the error the time
period from three hundred thousand years ago to the end
of the UM not Paleozoic. Did I say that, I

(12:22):
meant Pleistocene. So the three hundred thousand years to the
end of the Pleistocene is called the Rancho Lebray in
all one word land mammal age. They renamed it for
all this activity. Right. Yeah, like that's how important these
little pits of bitumen are. And we'll talk about how
all of this was discovered in just a moment. So chuck,

(12:47):
if this, if these are basically pools of bubbling crude,
sticky asphalt, how did a bone ever get pulled out
of it? Well, because of progress, my friend, and the
fact that Los Angeles was not going to uh sorry,
Pueblo de Arienna de Los Angeles. Um, it was bound

(13:13):
to be developed because of the weather there and the
beautiful Pacific coast and um, so progress people came along
and started making a city there, and uh, it's such
a volatile area. They realized, hey, this is you know,
this is dangerous this area right here until let's start
drilling for oil. Yeah. And it was I think the

(13:34):
Hancock family, Yeah, of Hancock Park fame, which is right
there as well. I'm more McArthur Park person. Yeah. Wow,
it's a good song. Okay, I thought you met you
just like scoring cheap drugs and literally someone leaving a
cake out in the rain. Yeah. MacArthur Parks not the
greatest area, no, but it's a it was a good,

(13:55):
good song. Yeah. But Hancock Park boy, is that nice? Well? Sure, yeah,
I say that like it should be obvious, but I
don't know where. Yeah, it is nice. Okay, so we're
talking about progress. Yes, the Hancock family in eighteen seventy
started drilling for oil and they basically the pits have
been used um since by Paleo Indians for things like

(14:18):
um waterproofing canoes and stuff that stuff. You want to
patch a hole in a canoe, Sure, you can do
a lot worse than asphalt. Yeah, because before that was
before what's that like a new miracle tape that they make.
It's like one of those products you see on TV
type things. The only one I'm familiar with is that
spray that the guy on the clear PLEXI class boat

(14:39):
to holes drilled in. Yeah, this get stuff. But we
don't buzz market here, no, because we don't remember the
names of anything. That's true. But back then, this tar man,
I mean that was like that was magic to the
to the Native America and it's just sitting there just
don't get too close. And then when the Spaniards came
in and started using that area for cattle rustling. Uh,

(15:02):
they used it also for waterproofing for their roofs. They
also used it as fuel. Um. And then once the
Hancock family started digging for oil, they kind of left
the tar pits alone. But um, as far back as
eighteen seventy five, a guy named William Denton was the
first person to describe a fossil. Take him from the

(15:22):
bray of tarpet. Somebody gave him a saber tooth, tiger tooth,
canine tooth and then inspired him. It did, and so
UM the Nascent Natural History Museum from Los Angeles contacted
the Hancock family and said, hey, why don't you let
us start tooling around there? And they let them starting
in nineteen o one. Uh, they were allowed to basically

(15:47):
do some kind of random, small, misguided excavation. Yeah, they
were only concerned about the big daddy bones. Well, that
came in the thirties. In the thirties when they started
like really digging the pit a thought. Nineteen thirteen is
when they started their first full scale You're right, I'm sorry.
They also did in the thirties too, well, from nineteen

(16:08):
thirteen till now, right, Okay, So in nineteen thirteen they
started digging pits around the Librea tar pits further pits,
uh nine six of them in total. Yeah, they had
to dig down to these. They weren't just big natural
pools of black tark, because people would have seen that
previously and be like, hey, what's up with all that stuff? Right,
So they would dig down UM remove all of the bones,

(16:30):
and like you said, they were really only interested in
the big ones, so they kind of discarded and left
alone a lot of the bird bones and plant fossils
and all that stuff that's boring. And the other thing
they didn't do was catalog the bones together, so they
basically just threw them all into piles. And there's a
picture on the Page Museum's website of UM one of

(16:51):
the early lead excavators just surrounded by like boxes and
boxes of bones. I'm sure they were like, what do
we do with all this stuff? Yeah, they found something
like a million or so a million and a half bones,
I think. Yeah, they dug ninety six pits in total,
and uh, well, we'll talk about the new progress. But

(17:12):
before the new progress. They had close to four million fossils,
and that sounds like a lot, but they said you
only have to get like once every ten year or
some big animals. Well yeah, that was another thing too.
They're like, well, that doesn't make any sense. In forty
thousand years, how could you have you know, four million bones?
When they were saying, well, yeah, if you do the math,

(17:33):
I think if you have thirty or ten animals stranded
every decade, it would account for it. Yeah, surprise, it
would more than that. Yeah, you know, because I mean
animals wander into tar pits. Yeah, they might also get
smart and avoid tar pits when when they see their
mommy go in and not coming out. I guess so,
you know, because those little baby mastodonce didn't look like

(17:54):
they were going in. After they were out of there,
they went to the beach, they went to maccarth apart.
Score that's right, all right? So I said they dug
ninety six pits. Not all of them bore fruit. Uh,
quite a few of them did. And pitt number was
ninety one was noted for the bounty of fossils. It

(18:17):
provided it's always the fifth to last one. That isn't
that the same it's always the fifth to the last,
and they for about forty years they really concentrated on
Pitt ninety one. I don't think they're digging there and
right now, although they may have started again, and I
think they're hot and heavy on Project Well, should we
go ahead and go to Project three. We'll get to

(18:37):
Project twenty three in a second. Let's do a message
break real quick. Okay, okay, So let's talk about Project Yeah.

(18:59):
I think probably JE twenty three started in two thousand six,
and that was basically a plan to continue digging and
find more fossils and take better care with the small guys,
to get a more complete fossil record. And they call
it twenty three because they did a well, this whole
thing started because LACMA wanted to build a parking garage

(19:20):
and underground parking garage, yeah, which you can't do unless
you know, around that area because so volatile, without getting
some help from archaeologists. And so they ended up digging
twenty three just big chunks of land essentially in these crates.
Have you ever seen you know, if you buy a
fully grown tree from a nursery, it comes in a

(19:40):
huge box. Huge wooden plants or have never seen him
like that. That's what they used. Yeah. Well, and much
larger even, and some of them capable of like close
to sixty tons of soil and tar and bones or
whatever else is in there. And that's why they called
the project because there's twenty three of them and this
was two dozen six of their You, much more sophisticated

(20:01):
techniques than they were using even in the sixties. Um,
when they were really hitting pit one hard. Um that
sounded so stupid, Please forgive me everyone, But they're using
sophisticated techniques. And they they had the um luxury of
coming at these deposits from the side or from underneath,

(20:24):
rather than having to go down through the tar pits
from above. Um. So they really scored a lot of
like just a trove of deposits of bones, including um,
a wooly mammoth named zed them. Yeah, it was a
Columbian wooly mammoth. It was the most intact skeleton ever
found of a Columbian wooly mammoth. Yeah, and the wooly

(20:46):
mammoth you see um reconstructed at the Page Museum. Or
they were, like you said, they used to just put
all the bones together so those were bones made up
of all kinds of wooly mammothz is all zed or
eight percent of them is all dead. And they name
him Zed in honor of zero, the British way of
saying zero um. And the reason they named him zero

(21:09):
is because he represents basically like a new start and
understanding of not only that um, that species, but all
of the life around that era. Patient zero pretty much. Uh.
And the cool thing is, I mean, I like all
the campiness of the Page Museum, but one of the
really neat parts about it is they have what they

(21:30):
call the fish bowl. They have a the room where
they're doing this work is all glass, and you can
walk through and see all the skeletons that they put
together and all the funny old dated uh, holy mammoths
that are going. Yeah, you can pound on the glass
and go nerds scientists, we can do that. At the
very end of it, you can uh that they're in

(21:52):
they're brushing, and they have microscopes and all sorts of
neat little tools that scientists here. You want to wait
to the end anyway, so you can run off right
after you say that, and they're recording all this stuff
it's very detailed. Um, they're they're what they're doing is
they're getting a fossil record from that time like they
didn't have before because they were lazy in the nineteen on, right.

(22:16):
So one of the reasons why they're looking for this
fossil records because this is a particularly curious time period
that the Librea tar pits encapsulated. Literally, Um, they're humans
evolved the and well that's remember with the the early Americans.
The debate over that this is around that time, Um,

(22:37):
there was something called the late Pleistocene extinction. Um, there
were a lot You'll notice a lot of animals, large
animals that used to be in North America that aren't
any longer. There's no camels, there's no indigenous American horse
any longer, there's no American lion, and all of these animals,
these what are called megafauna, started dying off at about

(22:59):
the same time in North America, and scientists aren't really
sure why. And I think that's one of the reasons
they're so excited about zed is they're hoping he can
kind of tell them. There's three competing or um combination
hypotheses for what caused this extinction. Humans killed them. That's

(23:20):
one that humans either overhunted all of them or overhunted
a keystone species like mastodons that led to collapse of
the ecosystem as a whole. It doesn't seem likely to me.
I know the timeline suggests that, but I think that's correlation. Okay,
that's just my opinion. The other one is climate change
itself did that. This was the end of an ice age.

(23:40):
Temperatures were rising, sea levels were rising. Um It's possible
that a lot of these species just couldn't possibly adapt,
possibly because they were large, because this late Pleistocene extinction
was mostly among mammals um or animals a hundred pounds
or more. And then the third one is something called
hyper disse any highly infectious disease, possibly introduced by man

(24:05):
and then transferred from man to animal. I wonder if
they found a human bones and the tar pits at all.
I don't know. I haven't heard about that. Yeah, I
didn't come across anything like that either. You think they
would have made pretty big hey, that kind of thing. Actually, Josh,
I did something we rarely do, and I just looked
it up mid Chow and they did find a human

(24:26):
skull called the Libreya woman evidently like early on in
nineteen fourteen, and that I think that's the only human
bones that they've ever found. So there you have it.
There you have it. Do they have any idea where
like when she lived approximately ten thousand years wow? So
and she was like between because she was old. Supposedly

(24:50):
that's a fallacy. Yeah, once once you they had a
high infant mortality rate back then, which excuse the average
life expectancy downward. But once you survived infancy, you could
expect to live like to a nice ripe old age.
But anyway, it's possible that Zed will give us an
idea of what the heck happened at the late Pleistocene extinction,

(25:12):
because North America in particular had a peculiar, peculiarly large
die off like it happened elsewhere in roughly the same
time in other continents, but in North America it was big, massive.
So what happened? Maybe the humans killed them all? Maybe
I'm wrong, ask Z well, not necessarily, but there were

(25:35):
humans in other places to where the extinction wasn't nearly
as pronounced. Maybe there were vegetarians. So go to the
Libreo tar pits. Yeah, because he's dead with his ten
foot long tusks. It's an l A institution. Yeah that
if you were just fan of movies, they've shot all
kinds of movies in there, and yeah, it was a

(25:56):
great movie, Miracle Mile. Yeah, Anthony Edwards. Did you ever
seen that? No, you should check that out. That's a
little known U cult classic about nuclear war and uh,
the last like twenty four hours before the bomb is
supposed to hit l A. Really and it all takes
place at the Miracle Mile area. Their scenes in the

(26:18):
tar pits and there's a diner there right on will
shure that. I think Johnny's Diner. That's not even open anymore,
but they just keep it there because they filmed so
many movies there. Uh yeah, highly recommended by me. Nice, Well,
I will see your Miracle Mile. Yeah. Very eighties though,
like get ready for the synthesizer score for you. Have

(26:40):
you ever seen Night of the Comment? Oh, dude, I
love Night of the Comment. That's that's a good one too.
Nothing to do with nuclear bombs or l A, but
that's great super eighties. Yeah, I love that movie. Do
you have it? Oh? I was behind Anthony Edwards at
the Reality to Restore Sanity. Oh really, yeah, I'm thinking
the right guy, right, the guy from Top Gun. Yeah,

(27:01):
and you are yeah, yeah, sure, yeah and Miracle Revenge
of the Nerds. Yeah. I don't remember his name that one,
but it was that was his best role. I think. Um,
we saw the I don't know if you saw him,
but when we were in l A for uh that
TV show that we had, Remember when they brought us

(27:21):
out for the press weekend thing. Um, I can't rember
what that's called, but we the junket. Yeah, it was
a junk It's a junket. The two Revenge of the
Booger and um, the Carte and guy were both there
promoting their new show, and they walked by me and
I was like, holy cow, that's two nerds of the
Revenge of the Nerds gang. I remember you saying that.
It was pretty excited. I felt like I missed out.

(27:44):
That's all right, not seeing them. It really wasn't a
big deal. And we're Matt Damon and uh Michael Douglas
there too, promoting the Liberati movie. Yeah. I remember seeing
them and going, what are they doing together? And that
is what our TV show has to do? With behind
the Candle labruk uh. If you want to know about
more amazing connections, you can check us out on social media.

(28:07):
We're all over the place. We're on Twitter, s y
s K podcast, We're on Instagram and Pinterest, We're on Facebook,
dot com, slash stuff you should know. You can send
us an email to Stuff Podcast at how stuff works
dot com. The triumphant return of that U R L
and uh. If you want to know more about the
Libreria tar pits, I did this totally out of order?

(28:30):
What is wrong with me? Today? You got a case
of the Monday's weird? It's Wednesday, anyway, I guess we'll
leave it in Huh. No sense in recording something in
error over again. Well, and since no one ever knows
how to get in touch with us, it's clear that
most people tune out by this time anyway, right, okay? Well, anyway,
if you want to know more about the Libraria tarpets,

(28:51):
type that in the search bar how stuff works dot
com and that will bring up this listener mail. Uh
am Nizia expert is what I'm gonna call this. We
called out for amnesia experts and we got one. Uh
or she says, I sort of am. Her name is Maya.
She's a PhD student working on her dissertation and neuroscience.
She said, my work focus is on spatial working memory,

(29:13):
and our lab actually models human amnesia and rats. While
there were a few things that were nitpicky, nitpicklely wrong, um,
I most wanted to write in about your discussion of
short term in working memory. While in the podcast you
stated that there were two separate things, there were two
separate things, and that working memory forms a bridge between
STM and l t M. In fact, the term short

(29:34):
term memory is no longer really used in the memory field.
Working memory now encompasses what used to be referred to
as short term uh. The working part is in reference
to the fact that these items can be remembered as
long as the brain works at rehashing the information, like say,
repeating it to yourself, rather than for a certain arbitrary
period of time. That's why they use a Clydesdale to

(29:55):
represent working memory. There's also competing theories about the actual
limits of working memory, but our lab believes in as
shown that it is capacity dependent that the traditional idea
of seven items really holds true for simple things like
numbers or letters. In fact, the more complicated the information,
the fewer items your working memory can hold. It's amazing.

(30:17):
For example, why you can easily remember the ten digits
uh by repeating it in your head. You could only
remember one or two faces using the same strategy. Huh.
So that is from Maya Uh, and good luck on
your PhD studies. Thanks for correcting us too. Maybe it
would have held a little more weight if it come
after you got your PhD, but we appreciate you writing

(30:40):
in either way. If you want to be derided by
me or chuck a listener mail, or if you want
to just correct us uh, we appreciate that in all seriousness,
you can write to us, as I said before Stuff
podcast at how stuff works dot com. And while you're
on the computer, you might as well check out our beautiful,

(31:02):
luxurious home on the web, Stuff you Should Know dot com.
For more on this and thousands of other topics, visit
how stuff Works dot com.