social learning - difficult one

[aspirant1976]

Social learning in animals
is said to occur when direct
or indirect social interaction
Line facilitates the acquisition
(5) of a novel behavior. It
usually takes the form of
an experienced animal (the
demonstrator) performing a
behavior such that the naive
(10) animal (the observer) subsequently
expresses the
same behavior sooner, or
more completely, than it
would have otherwise. One
(15) example of social learning
is the acquisition of preferences
for novel foods.
Some experiments
have suggested that among
(20) mammals, social learning
facilitates the identification
of beneficial food items,
but that among birds, social
learning helps animals
(25) avoid toxic substances.
For example, one study
showed that when red-wing
blackbirds observed others
consuming a colored food
(30) or a food in a distinctly
marked container and then
becoming ill, they subsequently
avoided food
associated with that color
(35) or container. Another
experiment showed that
house sparrows consumed
less red food after they
observed others eating
(40) red food that was treated
so as to be noxious. Studies
on nonavian species have
not produced similar results,
leading researchers to
(45) speculate that avian social
learning may be fundamentally
different from that of
mammals.
But Sherwin’s recent
(50) experiments with domestic
hens do not support the
notion that avian social
learning necessarily facilitates
aversion to novel
(55) foods that are noxious or
toxic. Even when demonstrator
hens reacted with
obvious disgust to a specific
food, via vigorous head
(60) shaking and bill wiping,
there was no evidence that
observers subsequently
avoided eating that food.
Sherwin’s research team
(65) speculated that ecological
or social constraints during
the evolution of this species
might have resulted in there
being little benefit from the
(70) social learning of unpalatability,
for instance,
selective pressures for this
mode of learning would be
reduced if the birds rarely
(75) encountered noxious or
toxic food or rarely interacted
after eating such food,
or if the consequences of
ingestion were minimal.
(80) In a related experiment,
the same researchers
showed that if observer
hens watched demonstrator
hens react favorably to food
(85) of a particular color, then
observer hens ate more
food of that color than they
ate of food of other colors.
These results confirmed that
(90) avian species can develop
preferences for palatable
food through social learning.

Q5:
According to the passage, which of the following is true of the experiments on domestic
hens conducted by Sherwin’s research team?
A. Only a small number of observer hens appeared to learn to avoid food that was
demonstrated by other hens to be noxious.
B. Observer hens ingested food preferentially only after numerous instances of
witnessing demonstrator hens preferentially ingest that type of food.
C. Observer hens appeared unable to recognize when demonstrator hens found a
particular food especially palatable.
D. Demonstrator hens reacted adversely to ingesting certain novel foods.
E. Demonstrator hens altered their behavior less obviously in response to noxious
foods than in response to highly palatable foods.

[btit]

I think D.

Line 50 to 60 mentions that Demo hens reacted adversely to certain novel food.

A: Wrong: line 61 says: there was no evidence that observers subsequently avoided eating that food

B: Not stated anywhere in para

C: Wrong, as para says that observer hens respond positively for palatable food. line 82-87.

D: line 50-60 is in line with option D.

E: I didn't find this in para.

[akrish1982]

is it E?

[cooltutu]

I think it is C. Since the experiments showed that the observer hens didn't initially able to react to the disgust of the demonstrator hens because of minimal social interaction.

Please correct me if i am wrong.

[rockerz]

Yup..i guess the choice is between D and E..but E goes too far..the para never discusses the relative reactions. It does clearly indicate that they do react adversely (although it may not happen that often).

My answer: D.

OA?

[Fiver]

A & B are not covered in the passage.
C & E state the reverse of what is stated in the passage.

D is clear.

[anils]

I think D is correct answer. Refer line no. 56 - 63.

[Cloud9]

another vote for D. However, answer given is E.

[gsbedi21]

It is E as line 50-60 and 80-90 explains this behavior.

[Neochronic]

But there is no evidence for E which says that demostrators hens reacted less obviously to noxious foods than palatable foods.
I will go with D.

Any more explanations for E.