Lecture 5: Development of behavior

Question 1

Theory of development

Answer 1

Phenotype = genotype+ environment

genes switch on and off due to environmental cues

Question 2

Microarray technology

Answer 2

detect mRNA production genes

Question 3

Development of working behavior in honey bees

Answer 3

cleaning cells, feeding, packing pollen, foraging.

Question 4

Juvenile hormone

Answer 4

• made in corpora allata
• more in older bees
• hormone inject in young bees –> switch to foraging
• remove corpora allata–> no reaction
• lacking corpora allata, inject hormone –> switch to foraging

Question 5

ethyl oleate

Answer 5

juvenile hormone

Question 6

Development of sexual behavior of rats

Answer 6

• male + female genetically differ by Y chromosome
• Y chromosome produce testosterone, which restrain development of female sex organs
• testosterone affect sexual organs in embryo
• inject testosterone in newborn female –> unreceptive, but when matured, exhibits male sexual behaviors.
• gonard, testes removed from newborn male –> develop feminized brain, when adult have female behaviors.
• gonard removed, hormone of opposite sex injected in adult –> no reaction

Question 7

testosterone effect on behavior

Answer 7

organizational effect: on young animal brain

activation effect: trigger sexual behavior in adult animals

Question 8

development of maternal behavior in rats

Answer 8

after birth female stays close to newborn
ovarian hormones induce development of maternal behavior.

• sexually immature, exposed to newborn –> care for young
• ovaries removed from immature rats –> 1/3 likely care for newborn
• sterile, spayed female injected with estrogen –> most cared for newborn

Question 9

development of song in Zebra finch

Answer 9

Birds only sing when hormone injected during specific development stage.

Only make finch sings courtship songs

• inject testosterone in adult female –> does not sing
• new born female w/implanted estrogen –> sings
• songs more complex if hormone is injected 4 days after hatching
• masculinized female adults doesn’t sing, unless injected with testosterone when adult.

Question 10

development of song in white crowned sparrow

Answer 10

local dialect is due to environment

• birds in isolation doesn’t sing normal courtship songs
• birds match songs of their neighbors
• social experience has strong effect.

Question 11

development of song in brown-headed cowbird

Answer 11

social feedback affect development of cowbird songs

male-male & female-male experience (refer to lec)

Question 12

play behavior

Answer 12

social play, exercise, diverse or object play

benefit: practice for young activities, faster growth+ development, social relationship