WHAT IS INTELLIGENCE? CENTRAL DOGMAmcb.berkeley.edu/courses/mcb41/BehavioralGenetics.07.pdf · BEHAVIORAL GENETICS GENOTYPE (mutation) NERVOUS SYSTEM PHENOTYPE (behavior) BEHAVIORAL

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MCB41 Genetics and SocietyProfessor Mark A. Tanouye

BEHAVIORALGENETICS

No reading in textbook for additional information:http://www.ornl.gov/sci/techresources/Human_Genome/elsi/behavior.shtml

WHAT IS INTELLIGENCE?Example: Tanouye Boys - (Social/Societal Intelligence)

MATTHEW (28y) Logical

ADAM (25y) ArtisticCreative

DAVID (18y) IntuitiveBig Picture

MICHAEL (9y) MathVerbalSocial - humor

GATE testing

CENTRAL DOGMAGENE

mRNA

PROTEIN

FUNCTION

GENOTYPE[**mutation**]

PHENOTYPE[**mutant**]

.BEHAVIORAL

GENETICS

GENOTYPE(mutation)

NERVOUSSYSTEM

PHENOTYPE(behavior)

BEHAVIORALGENETICS

DOMESTICATIONselective breeding

behavioral traits, eg dogscomplex inheritance

ETHOLOGYanimal behavior study

under natural conditionscomplex inheritance

MUTATIONALGENETICS

abnormal behavioreg. Drosophila

Mendelian genetics

LEARNING &MEMORY

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DOMESTICATIONAgricultural domesticationIraq 10,000 yMexico 9,000 yChina 8,000 ySouth America 7,000 yE North America 4,000 y Subsaharan Africa 4,000 y

Agricultural domesticationIraq 10,000 yMexico 9,000 yChina 8,000 ySouth America 7,000 yE North America 4,000 y Subsaharan Africa 4,000 y

Domestic dog: first domestic plant or animalArcheology: 14,000y (first domestic dog remains)mtDNA: 135,000y

Canidae(canines, dog family, 34 species)

Order: Carnivora (origin: 40-60 My)(dog, cat, bear, hyena, seal, mongoose families)

Family: Canidae (origin: 50-60My)

Gray wolf and coyote (closest wild relatives)mtDNA: 4% different (2 My)

Gray wolf and dogmtDNA: 0.2% different (135,000y)

BORDERCOLLIE

1) intelligent and protective (like large flock guardian dogs)2) friendly with and desire to please (like passive sheepdogs)3) the instinct to herd is so strong, can cause problems in the home4) will chase anything that moves5) stalking behavior: intense stare, low-bellied crouch towards objective

History: 1894 cross-bred from different sheepdogs

AKC recognition: 1995

Behavior SIBERIAN HUSKY1) most important trait: instinct and desire to run, seemingly endlessly2) powerful pulling machine with incredible stamina3) affectionate, tolerant of small children (Three dog night)4) alert and outgoing; not possessive or territorial5) should never be trusted off-leash; can be gone in a manner of secondsThe legendary sweetness of temperament was no accident:100 miles out on the ice, a single man with twenty dogs, if there's a dog fight; he simply does not get home

Bred by Chukchi women (Northern Siberia)AKC recognition 1930

mutantmutant normalnormal

carriercarrier

HEREDITYgeneral

X

homozygote(mate)

X

& &

(recessive/dominant))

mutantmutant

carriercarrier

carriercarrier normalnormal

MENDELIAN GENETICSm

m +

+

m

+

m

+

Xmutant

homozygotenormal

Xcarrier

heterozygote

12

34

m

m24

m

+14

+

+13

m

+32

Gregor Mendel 1857Rediscovered 1900

IndependentAssortment ofChromosomes

Standard poodle 16th CGolden retriever 1868Beagle 1887German shepherd 1899 (linkage)

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MUTANT STRAIN

m

mXmutant

homozygote

m

m

m

m

mutanthomozygote

mutant

mutantX

Locus Affected Gene Product

bang senseless bss transcription factor?

easily shocked eas ethanolamine kinase

slamdance sda aminopeptidasetechnical knockout tko mito. ribosomal protein

jitterbug jbug filamin

stress-sensitive sesB adenine nucleotide translocaserock n roll rnr transcription factor

couch potato cou transcription factor

bang sensitive bas ?

knockdown kdn ?

Seizure-sensitive Mutants Are Bang-sensitive Paralytics

BEHAVIOR PHENOTYPE

• initial seizure• paralysis• recovery seizure• refractory period

MUTANT STRAIN

m

mXmutant

homozygote

m

m

m

m

mutanthomozygote

mutant

mutantX

COMPLEMENTATIONeas

eas +

+

+

+

sda

sda

+ sda

eas +

mutant phenotype mutant phenotype

X

normal phenotype(double carrier)

Gunther Stent - UCB, MCB

Seymour BenzerPurdue, CaltechMark Tanouye

Sydney BrennerRobert HorvitzJohn SulstonMCB41Gian Garriga

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DROSOPHILA PHOTOTAXIS MUTANTSCountercurrent Apparatus (S. Benzer ‘67)

start Trial 1 shift

All flies

restarttap down

bestresponders

non-responders

x 5

population of flies as “molecules” of behavior

0

1

2

3

4

5

0

1 2

3

4 5TOWARD LIGHT (NO. OF RESPONSES)A

WA

Y F

R. L

IGH

T (N

O. O

F RE

SPO

NSE

S) RUNNERS

NORMALLYPHOTOTACTIC

NON-PHOTOTACTIC

NEGATIVELYPHOTOTACTIC

SLUGGISH

DISTRIBUTION OF MUTANTS(2-d “chromatogram)

(a second separationaway fr light testsfor variations inmotor activity)

ETHOLOGYKonrad LorenzNikolas TinbergenKarl von Frisch (‘73)

Whole patterns ofanimal behavior undernatural conditions

Examples: honeybee waggle dancesea gull display behavior

ADAPTIVE SIGNIFICANCEevolution

IMPRINTINGhow an instinct is learnednature vs nurture

DISPLAY BEHAVIOROF SEAGULLS

N. Tinbergen ‘53

“Choking” call - advertising nest site“Oblique” and “Long” call - defense ofnest site

herring gull - shore breederkittiwake - cliff breeder

modified “choke” call for bothadvertising and defense; no room for“oblique” or “long” calls

WAGGLE DANCEHoneybee, decoded byKarl von Frisch, 1945

Performed by foragingworker bee at the hive afterdiscovery of food source.

Pattern of dance: repeated figure eightStraight run: waggles abdomen, vibrates wingsDirection of straight run: line of flight to food sourceDuration of straight run: flight distance

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Cricket SongD. Bentley, R. Hoy ‘74