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PROFESSOR: All right, a
little less time today,

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because I gave you a
little extra time on that

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00:00:28,900 --> 00:00:33,030
since you were obviously
needing a little more time.

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00:00:40,160 --> 00:00:44,190
For this class and
Friday's class,

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00:00:44,190 --> 00:00:49,470
after a little bit on early
evolution and behavior,

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00:00:49,470 --> 00:00:53,750
we'll say a little bit
about genetics and learning.

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00:00:53,750 --> 00:00:59,860
Then mostly Friday we'll get
to the topic of navigation

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00:00:59,860 --> 00:01:03,830
and migration, how
animals find their way

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00:01:03,830 --> 00:01:13,600
on foraging trips and other
behavior that involves movement

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00:01:13,600 --> 00:01:14,945
quite a ways from their homes.

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00:01:22,860 --> 00:01:25,350
There's not much in the
readings on these topics,

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00:01:25,350 --> 00:01:32,000
but they come up in
studies of the brain

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00:01:32,000 --> 00:01:35,370
and certainly belong
in a behavior class.

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I want to know the most
basic multipurpose movement

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00:01:39,020 --> 00:01:40,930
abilities of animals.

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00:01:40,930 --> 00:01:46,775
We talked about multipurpose
movement abilities already,

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00:01:46,775 --> 00:01:49,850
but I want to know what are
the multipurpose movement

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00:01:49,850 --> 00:01:52,950
abilities that you find even
in single-celled organisms.

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00:01:52,950 --> 00:01:55,880
In fact, you find them all the
way from protozoa to primates.

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00:01:58,980 --> 00:02:02,550
They're the ones we're familiar
with besides elementary life

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00:02:02,550 --> 00:02:12,494
support behaviors and movements
within the cell, we have these.

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00:02:12,494 --> 00:02:16,420
Even In protozoa you
have locomotor activity

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00:02:16,420 --> 00:02:18,610
for approach and
avoidance, foraging,

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00:02:18,610 --> 00:02:25,375
feeding, and for
escape from predators.

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00:02:25,375 --> 00:02:29,630
You have orienting movements
in response to sensory inputs,

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00:02:29,630 --> 00:02:33,730
and you have various
kinds of grasping.

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00:02:33,730 --> 00:02:36,850
Grasping doesn't always
mean manual grasping.

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00:02:36,850 --> 00:02:40,020
It can be oral
grasping, and so forth,

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00:02:40,020 --> 00:02:42,340
and other kinds of grasping.

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00:02:42,340 --> 00:02:46,860
If you're a snake,
obviously it's either oral,

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00:02:46,860 --> 00:02:51,010
or they have another
means of grasping.

39
00:02:51,010 --> 00:02:54,750
Then you have various
special purpose movements.

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00:02:54,750 --> 00:02:57,965
These vary a lot
more between species.

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00:03:00,780 --> 00:03:06,020
Is that any different now
for multicellular animals?

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00:03:06,020 --> 00:03:10,470
Actually all those
behaviors listed

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00:03:10,470 --> 00:03:12,690
for the single-celled
organisms apply

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00:03:12,690 --> 00:03:16,660
to multicellular
animals of all sorts.

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00:03:16,660 --> 00:03:21,040
I just want to point
out that invertebrates,

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00:03:21,040 --> 00:03:27,020
even if you just eliminate
the entire forebrain,

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00:03:27,020 --> 00:03:32,024
you find these basic movement
abilities represented.

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They're represented
in the midbrain.

49
00:03:34,910 --> 00:03:39,380
They're basic to the
organization of the midbrain--

50
00:03:39,380 --> 00:03:44,100
control of locomotion, control
of orienting movements,

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00:03:44,100 --> 00:03:47,510
and control of various
kinds of grasping movements.

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00:03:51,480 --> 00:03:56,470
But what we've been calling
the action-specific potential--

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00:03:56,470 --> 00:04:00,170
that is the motivation
behind these movements,

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00:04:00,170 --> 00:04:03,230
the motivations
that usually lead

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00:04:03,230 --> 00:04:12,090
to these various
multipurpose movements--

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00:04:12,090 --> 00:04:16,920
then the forebrain is
much more involved.

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00:04:16,920 --> 00:04:21,800
I want to try to summarize
basic support systems in very

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general terms, and then we'll
talk about the regulators

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and controllers of
behavior, which are really

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the motivational states
of the forebrain.

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I like the way the
neuroanatomists here

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at MIT for many years
while [INAUDIBLE] describe

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the basic supports underlying
all behavior as stabilities--

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three types of stabilities.

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What do we keep stable?

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We're talking about internal
automatisms and reflexes, what

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we call the mantle of reflexes.

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First of all, stability of
the internal environment,

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the vital functions,
respiration, breathing-- now

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does that involve behavior?

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00:05:10,940 --> 00:05:13,600
Well certainly, very simple
breathing behavior, of course,

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but if we have
trouble breathing,

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we'll see other
kinds of behavior

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to try to get enough oxygen.

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You have circulation
of the blood.

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That's regulated
by reflex actions.

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Regulation of the chemical
environment-- the blood,

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the lymphatic fluids, the
various extracellular fluids--

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that involves reflexes.

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Feedback control systems--
homeostatic mechanisms,

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generally.

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Then of course, we
regulate temperature,

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and that involves reflex actions
and involves fixed action

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patterns of various sorts.

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These vary somewhat
across species,

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but there's some similarity
in all the vertebrates.

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00:06:15,480 --> 00:06:17,620
That's stability of the
internal environment.

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00:06:17,620 --> 00:06:20,980
Then we have stability
in space, and this

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00:06:20,980 --> 00:06:26,550
includes postural support--
various reflex actions

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that we've talked about.

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It includes maintaining
balance and direction

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during locomotion, as well.

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That all can be called
stability in space.

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Some people would
say it also includes

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00:06:40,080 --> 00:06:42,660
other kinds of
spatially-oriented behavior,

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00:06:42,660 --> 00:06:45,890
including the
orienting behaviors.

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Finally, stability
in time-- if I just

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00:06:50,930 --> 00:06:56,300
am talking about the level of
automatisms, including reflexes

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00:06:56,300 --> 00:06:59,640
and feedback mechanisms,
then we're talking about-- we

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00:06:59,640 --> 00:07:01,970
have to include, though,
the temporal organization

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of the day-night
cycle, the circadian

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rhythms, and their entrainment
by the light-dark cycle,

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the cycle of the sun.

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We have longer and
shorter rhythms, as well,

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00:07:15,880 --> 00:07:20,250
but the major thing is
motivational persistence.

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Without our motivational
states, animals in general

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00:07:24,850 --> 00:07:29,280
would flit from one
thing to the other,

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00:07:29,280 --> 00:07:31,870
depending on what, at
the moment, was dominant.

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But motivation tends to persist,
and that gives some unity

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00:07:36,040 --> 00:07:39,340
to current behavior.

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00:07:39,340 --> 00:07:41,610
That's all part of
stability in time,

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00:07:41,610 --> 00:07:45,463
and it's all regulated
pretty automatically.

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Of course, stability in
time can be extended a lot

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00:07:51,850 --> 00:07:53,950
when you deal with
forebrain mechanisms.

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I'm asking here for
which of the three

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is the forebrain most important.

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I've already
answered it, really--

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it's stability in time.

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Above these basic
support systems

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00:08:15,840 --> 00:08:19,620
are the regulators of
behavior, the basic controllers

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00:08:19,620 --> 00:08:21,765
we call drives,
motivational systems.

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And I want to just list them.

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Now you actually
did this somewhat

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00:08:30,005 --> 00:08:33,380
when you talked about ethograms.

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It's really a similar thing.

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If we just talk about
the various kinds of what

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00:08:45,020 --> 00:08:48,380
behavioral neuroscientists
would call the controllers,

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or regulators of behavior.

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We, for example, can start
with ingestion, drives,

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or motivations, various related
drives-- foraging, predation.

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00:09:02,350 --> 00:09:05,610
Then a couple kinds of
defensive behavior--

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anti-predator motivation,
first of all, and then

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second, social,
defensive behaviors--

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00:09:12,870 --> 00:09:15,020
part of social behavior.

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Then the various drives
involved in reproduction--

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I'm not saying each of
these is a single drive,

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but we can group them.

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00:09:25,250 --> 00:09:27,380
Then we have one
that's often left out

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00:09:27,380 --> 00:09:29,730
by ethologists,
but not by Lorenz--

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00:09:29,730 --> 00:09:33,060
and it shouldn't be--
exploration of novelty.

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Novelty serves
various roles, which

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we'll talk about in a minute.

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Then various other motivations,
including motivations

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for elimination, for shelter
and nest construction,

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00:09:45,430 --> 00:09:49,490
for sleeping, for play,
various social motivations,

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00:09:49,490 --> 00:09:54,190
and we have to add to all
these innate behaviors,

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00:09:54,190 --> 00:09:56,310
the learned motivations.

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Because with learning, we
also can acquire motivations

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00:10:01,320 --> 00:10:06,490
associated with learned
behavior-- something which

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is not as well understood,
but it's clearly

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something we have to deal with.

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Just adding a little
detail, ingestion drives

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would include both hunger
and thirst-- the basic ones.

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And of course, you can
get abnormal drives, too,

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but those are abnormalities
acquired because of the reward

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00:10:32,340 --> 00:10:36,700
involved and because
of the availability

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00:10:36,700 --> 00:10:43,120
of artificial things like drugs.

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But in fact, animals
can also become abnormal

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in their hunger and thirst.

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That's why we talk about such
things as food addiction,

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for example.

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Then the other drives
related to feeding

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are foraging, predatory
attack, and various predators.

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00:11:04,060 --> 00:11:07,060
Prying in starlings
is a separate drive.

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00:11:09,900 --> 00:11:12,960
Poking with a spine is
separate in cactus finches,

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and so forth.

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Then for defensive behavior,
the various anti-predator

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00:11:19,890 --> 00:11:22,840
behaviors, we have both
escape and avoidance,

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two somewhat separate.

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We're going to deal with
that separately later on,

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and we'll see a video
about escape behavior.

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Then the various
types of defense

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at the level of social behavior
include territorial behavior,

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00:11:48,310 --> 00:11:50,730
maintenance of a
position in a hierarchy,

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achieving a position,
maintaining it, improving it,

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and so forth.

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These all involve specific
social motivations.

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And then various
reproductive drives--

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00:12:02,130 --> 00:12:06,310
just some essential ones
here-- pairing, involving,

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00:12:06,310 --> 00:12:11,105
roaming or searching,
advertising, selecting

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00:12:11,105 --> 00:12:17,300
or responding, which we
usually called mate selection.

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Then mating itself,
brood-tending-- various aspects

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00:12:21,330 --> 00:12:24,040
of parental behavior.

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00:12:24,040 --> 00:12:26,760
Exploration of
novelty-- just point out

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00:12:26,760 --> 00:12:29,520
some of the roles of that.

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00:12:29,520 --> 00:12:32,155
It plays a role in
security and defense.

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When we see something
novel, an animal

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will interrupt his
current behavior.

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If he didn't do that, he
often would be caught.

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00:12:47,540 --> 00:12:50,300
He improves his
ability to detect

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00:12:50,300 --> 00:12:52,690
the source of the predator
and the nature of the predator

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00:12:52,690 --> 00:12:53,950
by his orienting movements.

193
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Of course animals, even if
there's no predator turnaround,

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00:13:01,580 --> 00:13:07,260
will explore novelty and expand
what we call their cognitive

195
00:13:07,260 --> 00:13:09,250
map--- their map
of the environment,

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00:13:09,250 --> 00:13:10,750
their knowledge of
the environment--

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00:13:10,750 --> 00:13:13,460
which is crucial for their
ability to escape from

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predators.

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They're not escaping
into an unknown area,

200
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but areas they know well,
and they know the routes

201
00:13:23,170 --> 00:13:28,120
for getting back home or to
getting to a hiding place.

202
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It plays a role in ingestion.

203
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We talk about neophobia
and neophilia.

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00:13:34,380 --> 00:13:38,110
If animals are
starving, they tend

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to be more neophilic-- that
is, they will seek novel foods,

206
00:13:45,190 --> 00:13:49,180
whereas normally if food
is relatively plentiful,

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00:13:49,180 --> 00:13:50,965
they will be neophobic.

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00:13:50,965 --> 00:13:52,700
They will avoid novelty.

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00:13:56,240 --> 00:13:58,660
And it does play a
role in sexuality,

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00:13:58,660 --> 00:14:02,400
as well, more in some
species than others.

211
00:14:02,400 --> 00:14:05,350
There's many other
motivations that we've

212
00:14:05,350 --> 00:14:06,710
mentioned, some of them before.

213
00:14:11,290 --> 00:14:14,230
This is another topic
about genes and behavior,

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00:14:14,230 --> 00:14:15,920
and I point out here
at the beginning,

215
00:14:15,920 --> 00:14:19,580
that variations in
a single gene can

216
00:14:19,580 --> 00:14:21,780
result in variations
in behavior.

217
00:14:21,780 --> 00:14:25,540
I just want to know what
kind of effects on the body

218
00:14:25,540 --> 00:14:28,340
does such a gene have to have.

219
00:14:28,340 --> 00:14:31,580
Well it's a very simple answer.

220
00:14:31,580 --> 00:14:37,710
If a gene has a specific
effect on behavior,

221
00:14:37,710 --> 00:14:43,380
like it can be a gene-- if
the animal has it, like a bee,

222
00:14:43,380 --> 00:14:47,000
he engages in cleaning
out of the hive,

223
00:14:47,000 --> 00:14:50,460
and if he doesn't
have it, he doesn't.

224
00:14:50,460 --> 00:14:52,690
You have these two kinds
of bees-- the hygienic bees

225
00:14:52,690 --> 00:14:55,290
and the non-hygienic bees.

226
00:14:55,290 --> 00:14:56,495
What has to be different?

227
00:15:01,420 --> 00:15:04,890
What does the gene
have to cause?

228
00:15:04,890 --> 00:15:11,030
The gene, by itself,
knows, in single cells,

229
00:15:11,030 --> 00:15:13,553
the single cells aren't
controlling behavior.

230
00:15:17,530 --> 00:15:20,026
So why is behavior different?

231
00:15:20,026 --> 00:15:23,410
How can the gene result in
differences in behavior?

232
00:15:23,410 --> 00:15:25,500
Very simple-- must
be differences

233
00:15:25,500 --> 00:15:31,470
in the nervous system,
right, because that's

234
00:15:31,470 --> 00:15:36,650
the way we inherit
fixed action patterns.

235
00:15:36,650 --> 00:15:40,260
Fixed action patterns
depend on brain

236
00:15:40,260 --> 00:15:44,020
circuitry and other
aspects of the brain,

237
00:15:44,020 --> 00:15:47,190
including hormones, for example,
the chemical environment,

238
00:15:47,190 --> 00:15:50,720
and so forth.

239
00:15:50,720 --> 00:15:53,770
That's the kind of an
effect it has to have.

240
00:15:53,770 --> 00:15:56,330
Generally, at least in
invertebrates, the effect

241
00:15:56,330 --> 00:15:57,840
is on the central
nervous system.

242
00:16:02,800 --> 00:16:05,235
And I point out, besides
hormones here, it

243
00:16:05,235 --> 00:16:07,165
could be differences
in sensory input

244
00:16:07,165 --> 00:16:13,690
and so forth that could result
in changes in behavior-- that

245
00:16:13,690 --> 00:16:17,700
is if an animal inherited much
higher sensory acuity or much

246
00:16:17,700 --> 00:16:22,570
lower thresholds to respond
to certain types of inputs

247
00:16:22,570 --> 00:16:24,750
in the environment, it
will change its behavior.

248
00:16:27,800 --> 00:16:30,250
Going back to the bees,
here, the hygienic

249
00:16:30,250 --> 00:16:33,100
bees-- what are they?

250
00:16:33,100 --> 00:16:38,480
Why does a bee colony
need hygienic bees?

251
00:16:38,480 --> 00:16:39,800
What do those bees do?

252
00:16:39,800 --> 00:16:43,715
It's described in
Scott quite clearly.

253
00:16:48,640 --> 00:16:53,940
These are the bees that
are opening up the cells,

254
00:16:53,940 --> 00:16:58,720
pulling out dead or
dying larvae, getting rid

255
00:16:58,720 --> 00:17:02,200
of them, dumping them out.

256
00:17:02,200 --> 00:17:04,115
But not all bees do that.

257
00:17:08,980 --> 00:17:13,040
At least if you
observe, say, a colony

258
00:17:13,040 --> 00:17:15,810
of many hundreds
of bees, you'll see

259
00:17:15,810 --> 00:17:21,069
only a certain percentage of
them will actually do that.

260
00:17:21,069 --> 00:17:22,280
The others just don't.

261
00:17:25,770 --> 00:17:30,310
Scott uses this as an
example of genes in behavior,

262
00:17:30,310 --> 00:17:33,270
and he discusses it
in terms of two genes.

263
00:17:39,060 --> 00:17:48,490
It's all based on one study
that showed that you can create

264
00:17:48,490 --> 00:17:55,280
a colony where there's
no hygienic bees,

265
00:17:55,280 --> 00:17:59,370
and you can have colonies
with many more hygienic bees.

266
00:17:59,370 --> 00:18:01,790
The evidence is,
from the paper he

267
00:18:01,790 --> 00:18:05,700
was studying, that it's
based on two genes.

268
00:18:05,700 --> 00:18:12,740
Both tend to be
dominant, and if they

269
00:18:12,740 --> 00:18:18,700
possess the non-dominant allele,
then they will be hygienic.

270
00:18:18,700 --> 00:18:20,690
But why are there two genes?

271
00:18:20,690 --> 00:18:25,000
Because there's two behaviors
involved, and they apparently,

272
00:18:25,000 --> 00:18:29,310
according to this study,
they inherit separately

273
00:18:29,310 --> 00:18:33,460
the ability to do
one or the other.

274
00:18:33,460 --> 00:18:36,490
In order to find dead
larvae or dying larvae,

275
00:18:36,490 --> 00:18:40,520
they have to be able to
open the cell in the hive--

276
00:18:40,520 --> 00:18:45,080
so he calls that
uncapping-- and the other

277
00:18:45,080 --> 00:18:48,600
involves actually
getting into the cell

278
00:18:48,600 --> 00:18:50,350
and pulling out the dead larvae.

279
00:18:50,350 --> 00:18:52,220
That's another
kind of behavior--

280
00:18:52,220 --> 00:18:54,990
so two distinct behaviors.

281
00:18:54,990 --> 00:18:57,000
And the genetic studies
indicate that you

282
00:18:57,000 --> 00:19:02,170
can have bees that will
uncap, but won't clean out.

283
00:19:02,170 --> 00:19:04,470
And you can have other
bees that won't uncap,

284
00:19:04,470 --> 00:19:07,890
but they will clean
out dead larvae.

285
00:19:07,890 --> 00:19:11,320
That's why they concluded there
have to be two separate genes.

286
00:19:14,180 --> 00:19:23,980
Then he goes on, and he
points out that in a colony,

287
00:19:23,980 --> 00:19:25,700
you can have a
colony, let's say,

288
00:19:25,700 --> 00:19:30,970
that contains all hygienic
bees, but they don't all

289
00:19:30,970 --> 00:19:33,720
engage in hygienic behavior.

290
00:19:33,720 --> 00:19:38,980
You can have a colony that
involves half hygienic bees,

291
00:19:38,980 --> 00:19:44,900
but 50% of them don't
engage in hygienic behavior.

292
00:19:44,900 --> 00:19:48,580
Furthermore, they engage in the
behavior only when they reach

293
00:19:48,580 --> 00:19:51,960
a certain age, and
the age at which they

294
00:19:51,960 --> 00:19:54,330
start their hygienic
behavior will actually

295
00:19:54,330 --> 00:19:58,275
depend on the proportion of
hygienic bees in the colony.

296
00:20:00,940 --> 00:20:04,720
If there's many more, they
will engage at an older age.

297
00:20:04,720 --> 00:20:08,090
If there's very few, then
they will start younger.

298
00:20:10,890 --> 00:20:15,490
He spells out the
numbers for that.

299
00:20:15,490 --> 00:20:20,130
I went to one of the
studies he was using.

300
00:20:20,130 --> 00:20:22,370
The title I listed
for you, there--

301
00:20:22,370 --> 00:20:25,010
"Influence of Colony
Genotype Composition

302
00:20:25,010 --> 00:20:30,980
on the Performance of Hygienic
Behavior in the Honey Bee."

303
00:20:30,980 --> 00:20:37,210
They describe the creation
of four colonies that

304
00:20:37,210 --> 00:20:43,140
had 25% hygienic bees,
100% hygienic bees,

305
00:20:43,140 --> 00:20:47,750
or 0% hygienic bees.

306
00:20:47,750 --> 00:20:49,930
This is from their
table, where they're

307
00:20:49,930 --> 00:20:52,380
summarizing many of the results.

308
00:20:52,380 --> 00:20:56,750
Here's the percentage
of hygienic bees,

309
00:20:56,750 --> 00:21:00,250
and the 100n means
100% non-hygienic,

310
00:21:00,250 --> 00:21:02,530
so that's 0% hygienic bees.

311
00:21:05,620 --> 00:21:07,380
Here they're just
listing the number

312
00:21:07,380 --> 00:21:09,810
of bees that are
hygienic or nonhygienic.

313
00:21:09,810 --> 00:21:11,860
The nonhygienic ones
are in parentheses.

314
00:21:11,860 --> 00:21:14,170
You'll see that
there are 1,600 bees.

315
00:21:14,170 --> 00:21:16,760
They adjusted the numbers
in these four colonies--

316
00:21:16,760 --> 00:21:21,840
so there are 1,600 bees in
each of the four colonies.

317
00:21:21,840 --> 00:21:27,210
They went from being all
hygienic and no hygienic,

318
00:21:27,210 --> 00:21:30,733
and then the in between
ones here-- 400 and 1,200,

319
00:21:30,733 --> 00:21:34,780
and 800 and 800.

320
00:21:34,780 --> 00:21:40,720
Then here's the statistics on
how many of them are actually

321
00:21:40,720 --> 00:21:42,780
engaging in hygienic behavior.

322
00:21:42,780 --> 00:21:46,260
You can see that if only
25% of them were hygienic,

323
00:21:46,260 --> 00:21:53,290
then almost 79% of them
engaged in hygienic behavior.

324
00:21:53,290 --> 00:22:02,320
If half of them were
hygienic, then almost 40%

325
00:22:02,320 --> 00:22:07,070
If all of them were hygienic,
only about 19% of them

326
00:22:07,070 --> 00:22:11,060
would engage in hygienic
behavior in this study.

327
00:22:11,060 --> 00:22:17,470
Of course, if none of
them were hygienic,

328
00:22:17,470 --> 00:22:22,690
then they are only looking
at the hygienic behavior

329
00:22:22,690 --> 00:22:24,980
of the two kinds of bees.

330
00:22:24,980 --> 00:22:28,420
But they looked at the
nonhygienic behavior--

331
00:22:28,420 --> 00:22:41,450
sorry, nonhygienic behavior in
hygienic and nonhygienic bees.

332
00:22:41,450 --> 00:22:44,610
It's very interesting, the
nonhygienic bees actually

333
00:22:44,610 --> 00:22:49,120
do engage in some
hygienic behavior,

334
00:22:49,120 --> 00:22:52,990
so that doesn't quite
fit the genetic study.

335
00:22:52,990 --> 00:22:55,590
That led me to look
a little further,

336
00:22:55,590 --> 00:22:57,190
and I found another paper.

337
00:22:57,190 --> 00:22:59,680
It included one of
the same authors,

338
00:22:59,680 --> 00:23:02,330
which is how I found it.

339
00:23:02,330 --> 00:23:04,830
It was published the same year
in the Journal of Comparative

340
00:23:04,830 --> 00:23:10,210
Physiology, and it was entitled
"Olfactory and Behavioral

341
00:23:10,210 --> 00:23:17,230
Response Thresholds to Odors
of Disease Brood Differ Between

342
00:23:17,230 --> 00:23:19,122
Hygienic and
Nonhygienic Honey Bees."

343
00:23:19,122 --> 00:23:20,580
They had a couple
of different ways

344
00:23:20,580 --> 00:23:23,367
of looking at how sensitive
they were to odors.

345
00:23:23,367 --> 00:23:25,450
They were interested, of
course, in their response

346
00:23:25,450 --> 00:23:30,100
to the odor of dying
or dead larvae,

347
00:23:30,100 --> 00:23:35,370
and they found that the
hygienic and nonhygienic bees

348
00:23:35,370 --> 00:23:37,370
showed different thresholds.

349
00:23:37,370 --> 00:23:41,810
The hygienic bees were much
more sensitive to the odor.

350
00:23:41,810 --> 00:23:47,180
They had inherited different
olfactory abilities.

351
00:23:47,180 --> 00:23:51,640
But it wasn't that the
nonhygienic bees couldn't

352
00:23:51,640 --> 00:23:54,860
detect the odor of
the dying larvae.

353
00:23:54,860 --> 00:23:57,157
They just had much
higher thresholds,

354
00:23:57,157 --> 00:23:58,990
so it was more difficult
for them to detect.

355
00:24:04,510 --> 00:24:08,880
So that may explain why the
nonhygienic bees sometimes

356
00:24:08,880 --> 00:24:11,900
do clean out a cell
of dead larvae.

357
00:24:11,900 --> 00:24:17,220
They not only can
smell, just not as well.

358
00:24:17,220 --> 00:24:19,570
But they can also engage
in hygienic behavior,

359
00:24:19,570 --> 00:24:22,230
if they actually detect it.

360
00:24:22,230 --> 00:24:25,140
But usually they're not
engaging in such behavior,

361
00:24:25,140 --> 00:24:27,930
because they don't notice it.

362
00:24:27,930 --> 00:24:30,780
That's probably much more
efficient for a bee colony.

363
00:24:33,730 --> 00:24:36,640
You don't need all
bees doing that.

364
00:24:36,640 --> 00:24:38,100
What you need the
rest of them for?

365
00:24:38,100 --> 00:24:39,630
These are worker
bees, and you want

366
00:24:39,630 --> 00:24:44,720
them to go out and
get the nectar,

367
00:24:44,720 --> 00:24:47,880
bring it back to the
hive, feed those larvae,

368
00:24:47,880 --> 00:24:50,700
because most of them,
of course, are alive,

369
00:24:50,700 --> 00:24:55,290
unless the colony is suffering
from some pathology, which

370
00:24:55,290 --> 00:24:56,490
does occur in bees.

371
00:25:00,020 --> 00:25:04,500
The study completely
neglected the topic

372
00:25:04,500 --> 00:25:08,790
that Scott had emphasized-- the
difference between uncapping

373
00:25:08,790 --> 00:25:11,390
and removal behavior.

374
00:25:11,390 --> 00:25:13,870
This later study, in spite
of one of the authors

375
00:25:13,870 --> 00:25:17,310
being the same, they
didn't mention that.

376
00:25:17,310 --> 00:25:21,790
I'm not going to make any
attempt to reconcile that.

377
00:25:21,790 --> 00:25:24,940
This is typical in science.

378
00:25:24,940 --> 00:25:27,750
They don't completely
satisfy you with any study,

379
00:25:27,750 --> 00:25:31,820
but it did explain quite a
bit about why some bees engage

380
00:25:31,820 --> 00:25:33,240
in the behavior
and others don't.

381
00:25:39,310 --> 00:25:41,830
A little more about
genes and behavior--

382
00:25:41,830 --> 00:25:45,370
we talk about genetic fitness.

383
00:25:45,370 --> 00:25:46,600
What is genetic fitness?

384
00:25:50,040 --> 00:25:56,910
Direct genetic fitness means
how many offspring you have.

385
00:25:56,910 --> 00:26:00,710
That's one measure of
your genetic fitness.

386
00:26:00,710 --> 00:26:03,235
We can also talk about
inclusive fitness.

387
00:26:07,760 --> 00:26:10,870
How do we define
inclusive fitness?

388
00:26:10,870 --> 00:26:19,180
It was a major issue for
Charles Darwin, this issue.

389
00:26:19,180 --> 00:26:24,300
How could sterile workers
evolve in social insects?

390
00:26:24,300 --> 00:26:28,810
Sterile workers are
not having offspring.

391
00:26:28,810 --> 00:26:37,630
Sterile workers are the
daughters of a queen,

392
00:26:37,630 --> 00:26:43,550
but they share a lot of
genes with that queen.

393
00:26:43,550 --> 00:26:51,920
In fact, because of the
genetics of these hymenoptera,

394
00:26:51,920 --> 00:26:55,820
they usually share
75% with the mother.

395
00:26:55,820 --> 00:26:59,660
That depends, if she only
mated with one male anyway.

396
00:26:59,660 --> 00:27:02,770
We'll come back to this topic
when we deal with sociobiology.

397
00:27:02,770 --> 00:27:05,280
It's been a major
topic, and it's

398
00:27:05,280 --> 00:27:08,050
led to a number of new
findings by a sociobiologist.

399
00:27:10,580 --> 00:27:16,440
The point is because of the
work of those sterile workers,

400
00:27:16,440 --> 00:27:19,320
their work for the colony,
promotes the survival

401
00:27:19,320 --> 00:27:22,620
and increase in
their genes, which

402
00:27:22,620 --> 00:27:26,010
they share with their
mother, the queen.

403
00:27:26,010 --> 00:27:30,690
They have inclusive fitness.

404
00:27:30,690 --> 00:27:34,130
Similarly, if you have a
human who has no offspring,

405
00:27:34,130 --> 00:27:37,630
it doesn't mean that his
inclusive fitness-- the broader

406
00:27:37,630 --> 00:27:41,420
definition of genetic
fitness-- isn't present.

407
00:27:41,420 --> 00:27:45,150
If he is doing
something to promote

408
00:27:45,150 --> 00:27:48,130
the survival of his
nieces and nephews,

409
00:27:48,130 --> 00:27:54,990
for example, of his
sister, whatever you see,

410
00:27:54,990 --> 00:27:57,570
he's promoting the
survival of his own genes.

411
00:27:57,570 --> 00:28:04,400
He shares 50% with his siblings.

412
00:28:04,400 --> 00:28:08,740
He shares 25% with his
nieces and nephews.

413
00:28:08,740 --> 00:28:11,470
That's why the concept
of inclusive fitness

414
00:28:11,470 --> 00:28:12,430
is so important.

415
00:28:12,430 --> 00:28:15,660
It's, in fact,
necessary to explain

416
00:28:15,660 --> 00:28:20,950
the evolution of specific
types of behavior.

417
00:28:27,960 --> 00:28:30,170
Let's say a little bit
about learning, and starting

418
00:28:30,170 --> 00:28:32,365
with very simple kinds
of learning-- habituation

419
00:28:32,365 --> 00:28:35,990
and sensory adaptation.

420
00:28:35,990 --> 00:28:39,642
You should know the
definitions of habituation

421
00:28:39,642 --> 00:28:40,975
and sensory adaptation.

422
00:28:43,550 --> 00:28:48,170
Scott's textbook describes
briefly just habitation, not

423
00:28:48,170 --> 00:28:51,400
sensory adaptation.

424
00:28:51,400 --> 00:28:54,370
You can easily find
an answer to that,

425
00:28:54,370 --> 00:28:56,820
and you should be able to give
definitions of habituation.

426
00:29:02,710 --> 00:29:05,170
I'm asking a question
there about habituation

427
00:29:05,170 --> 00:29:06,590
to different kinds of stimuli.

428
00:29:06,590 --> 00:29:09,020
Let's just start
with definitions

429
00:29:09,020 --> 00:29:10,605
for these two terms.

430
00:29:13,860 --> 00:29:17,190
In both cases, there's
a decreased response

431
00:29:17,190 --> 00:29:20,420
with repeated presentation
of the same stimulus.

432
00:29:25,410 --> 00:29:29,400
Say I'm touching your
back of your hand.

433
00:29:29,400 --> 00:29:32,040
I'm sitting next to
you, you know me well,

434
00:29:32,040 --> 00:29:34,970
and I'm jiggling my hand,
and I'm touching you.

435
00:29:34,970 --> 00:29:39,330
You notice it at the
beginning, but pretty soon you

436
00:29:39,330 --> 00:29:40,140
habituate to it.

437
00:29:40,140 --> 00:29:40,670
Or did you?

438
00:29:40,670 --> 00:29:42,240
Maybe just adapt to it.

439
00:29:42,240 --> 00:29:43,969
Maybe it's sensory adaptation.

440
00:29:43,969 --> 00:29:44,885
What's the difference?

441
00:29:48,390 --> 00:29:52,230
Habituation is more
central, and we

442
00:29:52,230 --> 00:29:54,980
can go to physiology
and define it that way.

443
00:29:59,460 --> 00:30:06,420
It's closer to the motor side,
and the level of the response

444
00:30:06,420 --> 00:30:09,870
depends on the
degree of novelty.

445
00:30:09,870 --> 00:30:13,610
The more this stimulus occurs,
the less and less novel

446
00:30:13,610 --> 00:30:17,580
it is, the more expected it
is-- less and less response.

447
00:30:17,580 --> 00:30:19,310
In the case of
sensory adaptation,

448
00:30:19,310 --> 00:30:21,820
the actual-- and this
usually happens right

449
00:30:21,820 --> 00:30:27,435
at the receptor level-- you
get less and less response.

450
00:30:27,435 --> 00:30:29,520
The receptors are
just not sending

451
00:30:29,520 --> 00:30:32,750
as many impulses to the
central nervous system.

452
00:30:32,750 --> 00:30:34,810
It's a kind of fatigue.

453
00:30:34,810 --> 00:30:40,235
That's sensory adaptation,
and when the stimulus stops,

454
00:30:40,235 --> 00:30:41,360
there's a gradual recovery.

455
00:30:44,590 --> 00:30:46,420
The same is true for habitation.

456
00:30:46,420 --> 00:30:51,895
There is recovery, but the
mechanism is very different.

457
00:30:55,420 --> 00:30:59,130
In the case of a habituation,
it's really difficult

458
00:30:59,130 --> 00:31:02,298
to define it as a
kind of fatigue,

459
00:31:02,298 --> 00:31:04,830
although people have
thought of it as fatigue

460
00:31:04,830 --> 00:31:06,300
at the more central level.

461
00:31:09,050 --> 00:31:11,470
Think of examples
of habituation,

462
00:31:11,470 --> 00:31:16,290
and tell me if you can habituate
to both simple and complex

463
00:31:16,290 --> 00:31:16,790
stimuli.

464
00:31:16,790 --> 00:31:23,030
Can you habituate to
several bars of Mozart?

465
00:31:23,030 --> 00:31:27,260
You can certainly habituate
to a ticking of a clock.

466
00:31:27,260 --> 00:31:29,850
You can habituate
to cars going by.

467
00:31:29,850 --> 00:31:32,560
You live on a busy
street like I do,

468
00:31:32,560 --> 00:31:34,725
pretty soon you're
ignoring most of it--

469
00:31:34,725 --> 00:31:36,930
a particularly
loud truck goes by,

470
00:31:36,930 --> 00:31:39,200
something changes,
yeah you notice it,

471
00:31:39,200 --> 00:31:41,130
but most the time,
you're not even

472
00:31:41,130 --> 00:31:43,680
noticing that you're
habituated to it.

473
00:31:43,680 --> 00:31:47,130
You don't normally
notice the clock.

474
00:31:47,130 --> 00:31:50,180
You don't notice internal
sounds in your body

475
00:31:50,180 --> 00:31:51,750
unless they change a lot.

476
00:31:51,750 --> 00:31:52,960
You habituate to it.

477
00:31:56,540 --> 00:31:59,120
What about the bars of Mozart?

478
00:31:59,120 --> 00:32:01,860
Can you habituate to it?

479
00:32:01,860 --> 00:32:03,000
Yes you can.

480
00:32:03,000 --> 00:32:06,180
You can habituate to
complex stimuli, too.

481
00:32:06,180 --> 00:32:12,150
In fact, in tests
of habituation,

482
00:32:12,150 --> 00:32:17,170
it's when something changes
that you get a new response.

483
00:32:17,170 --> 00:32:20,780
So in formal tests, you
might use series of stimuli.

484
00:32:20,780 --> 00:32:24,750
They often use rhythmic stimuli,
and they can then suddenly

485
00:32:24,750 --> 00:32:28,700
leave out one stimulus
in the rhythm.

486
00:32:28,700 --> 00:32:32,970
It sounds different, and
the animal or the person

487
00:32:32,970 --> 00:32:35,115
will make an orienting response.

488
00:32:42,840 --> 00:32:45,250
You can respond to
the sudden absence

489
00:32:45,250 --> 00:32:48,356
of the stimulus, any
detection of novelty.

490
00:32:48,356 --> 00:32:49,480
Now what are the responses?

491
00:32:52,850 --> 00:32:56,670
We won't be able to get
much beyond this today.

492
00:32:56,670 --> 00:33:00,710
All of these terms are used
in describing responses

493
00:33:00,710 --> 00:33:02,715
to novel stimuli--
the arousal response,

494
00:33:02,715 --> 00:33:06,100
the orienting response,
orienting reflex

495
00:33:06,100 --> 00:33:09,600
is commonly used,
especially in the east.

496
00:33:09,600 --> 00:33:12,635
This has been studied
a lot in Russia.

497
00:33:16,600 --> 00:33:20,380
We talk about
curiosity for novelty.

498
00:33:20,380 --> 00:33:24,310
That is also a
response to novelty.

499
00:33:24,310 --> 00:33:28,850
There's responses at
the autonomic level,

500
00:33:28,850 --> 00:33:30,920
involving the autonomic
nervous system.

501
00:33:30,920 --> 00:33:32,900
What are those responses?

502
00:33:32,900 --> 00:33:36,580
Heart rate change-- it's
usually a heart rate increase,

503
00:33:36,580 --> 00:33:38,470
but if the heart's
beating very fast already,

504
00:33:38,470 --> 00:33:44,790
it will actually slow
down-- altered breathing,

505
00:33:44,790 --> 00:33:50,150
increased muscle
tension, basal dilation

506
00:33:50,150 --> 00:33:53,100
in the head, basal
constriction in the limbs.

507
00:33:53,100 --> 00:33:56,240
Interesting that it's different
in the head and in the limbs.

508
00:33:56,240 --> 00:33:58,600
In the head, where you
have only head senses,

509
00:33:58,600 --> 00:34:03,430
it's different than the limbs.

510
00:34:03,430 --> 00:34:04,980
You can specifically
measure that.

511
00:34:04,980 --> 00:34:06,690
You can measure the
volume of the finger,

512
00:34:06,690 --> 00:34:09,489
for example, with
a plethysmograph.

513
00:34:09,489 --> 00:34:12,812
It's easy to hook up a
cuff around the finger

514
00:34:12,812 --> 00:34:15,760
and measure the
volume and record it

515
00:34:15,760 --> 00:34:20,820
in a pretty sensitive way, and
you will see the basal dilation

516
00:34:20,820 --> 00:34:22,580
or basal constriction.

517
00:34:22,580 --> 00:34:24,400
Then there's
behavioral responses--

518
00:34:24,400 --> 00:34:31,110
alerting responses-- orientation
of the head, eyes, and ears.

519
00:34:31,110 --> 00:34:33,230
Exploratory behaviors--
so now we're

520
00:34:33,230 --> 00:34:37,060
not just talking about
orienting and alerting.

521
00:34:37,060 --> 00:34:39,750
I'm talking about
approach and manipulation,

522
00:34:39,750 --> 00:34:43,719
all behavioral
responses to novelty.

523
00:34:43,719 --> 00:34:49,350
Then finally we have a
motivation to seek novelty,

524
00:34:49,350 --> 00:34:51,850
especially in
higher vertebrates.

525
00:34:51,850 --> 00:34:56,650
Exploratory behavior occurs
caused by a motivation

526
00:34:56,650 --> 00:35:00,915
to seek novelty that we call
the motivation of curiosity.

527
00:35:03,580 --> 00:35:08,150
I want to point out here
that a novel stimulus can

528
00:35:08,150 --> 00:35:11,970
be seen as a conflict between
expected input and perceived

529
00:35:11,970 --> 00:35:13,230
input.

530
00:35:13,230 --> 00:35:14,850
If you look at it--
this is the way

531
00:35:14,850 --> 00:35:17,460
a cognitive psychologist
would look at it--

532
00:35:17,460 --> 00:35:23,860
and it corresponds very
well to what's happening--

533
00:35:23,860 --> 00:35:27,730
and I point out here that the
autonomic changes are exactly

534
00:35:27,730 --> 00:35:32,190
the same as measured
by a lie detector.

535
00:35:32,190 --> 00:35:33,770
What does a lie
detector measure?

536
00:35:37,190 --> 00:35:40,870
Lies cause a different
kind of conflict.

537
00:35:40,870 --> 00:35:43,930
In both cases we're dealing with
conflict, and in both cases,

538
00:35:43,930 --> 00:35:48,590
we get these same
autonomic responses.

539
00:35:48,590 --> 00:35:51,910
If in a lie detection-- that's
why the skill of the person

540
00:35:51,910 --> 00:35:54,890
administering the
test is so critical.

541
00:35:54,890 --> 00:35:58,130
He can get the autonomic
responses, just

542
00:35:58,130 --> 00:36:04,135
by introducing novelty, and he
has to be very aware of that.

543
00:36:10,070 --> 00:36:14,200
We'll start by talking more
about other kinds of learning,

544
00:36:14,200 --> 00:36:18,026
including associative learning
and conditioning next time.