of PBS video on animal reasoning and language.
How are humans different from other animals?
BIAS can lead to this. If an experimenter believes that (or hopes that) animals
have a certain ability, she might give the animal hints or cues. The most famous
example of this is Clever Hans. In the early 1900s, a horse named Hans and his
trainer (Wilhelm von Osten) were well known for their amazing performances.
Someone in the audience would ask Hans to add 4 and 3. Hans would stamp his hoof
psychologist named Oskar Pfungst was skeptical. He showed that if the trainer
didn't know the right answer, Hans couldn't figure it out either. Hans wasn't
really counting ? he was just responding to subtle cues from his trainer. If
the right answer was 11, the trainer wouldn't smile or relax until Hans stomped
are a few possible cases of this on the video. In one study, a chimp must point
to a number on a television screen corresponding to how many objects he just
saw. Unlike the well controlled experiment with dolphins (where the experimenter
wore goggles to prevent giving signals to the animal), in this case, the
experimenter gave off a lot of verbal and non-verbal "hints" about the
right answer. It is very appropriate to be skeptical when an animal gets the
right answer in a situation like this.
(term coined by Princeton University philosopher Peter Singer):
assuming that humans are qualitatively different from other species.
BIAS (interpreting things in a way that favors your own interests) can lead to
this. Given that humans use animals for so many purposes, we are motivated to
perceive them as being different from us (not conscious, not capable of reason,
Only humans have consciousness and the ability to experience pleasure and
general question: Do animals show evidence of abilities that go beyond trial and
error learning? Do they show evidence of having mental representations (maps,
concepts, understanding of language, arithmetic)? Can they solve problems by
figuring them out (insight) as opposed to just trying things until something
works (trial and error)?
Use of MENTAL MAPS.
in maze could find a NEW way to get to food when the old route was blocked.
could remember which (fake) plants they had already eaten from.
could remember routes to water.
nutcrackers could remember where 90% of 30,000 pine seeds were buried (even
under the snow).
Creative problem solving.
getting banana using boxes and sticks (replication of a very famous study by
Maybe the chimp just tried things over and over (trial and error) until he
finally hit on the right solution.
get around this objection, it is necessary to demonstrate an animal can solve a
NEW task on the FIRST trial.
experiment with raven: food is at the end of one string but not another. Can the
raven figure out how to get food, EVEN THOUGH IT HAS NEVER ENCOUNTERED THIS
PARTICULAR PROBLEM BEFORE? IF IT CAN FIGURE OUT ON THE FIRST TRY, it RULES OUT
trial and error. Even when the strings are crossed, making the problem more
difficult, the raven solved it on the first trial.
Use of tools.
using sticks, leaves as weapons.
using twigs to get insects out of trees.
Learning through imitation.
washing clothes and self.
imitating other dolphins (and also humans)
Representing abstract concepts.
design of the task with the pigeons pecking at pictures for food.
A picture leads to food
B picture does NOT lead to food
Can the pigeon learn that it should peck at A but not at B?
could not learn to discriminate (A) two lines that were the SAME length from
two lines that were DIFFERENT lengths.
suggests: SAME/DIFFERENT is an abstract concept beyond capacity of pigeon.
could learn to discriminate (A) large area covered from (B) small area covered
the students had a tough time with this one ? humans look for patterns that
are meaningful ? "Large" vs. "Small" surface area of
randomly shaped patterns isn't a hypothesis that occurs to us.)
Understanding arithmetical concepts.
Irene Pepperberg (U of Arizona) has a parrot Alex who could count the
He says what would REALLY be impressive would be evidence that an animal could
experiment: can a chimp do arithmetic? Can a chimp ADD the number of apples in
one bowl to the number of oranges in another bowl and get the right total?
Answer was YES.
animals use something like words to communicate?
Dog: responded appropriately to down/cover your eyes/speak/crawl/etc.
BUT, humans can invent and use NEW words.
study: Alex the parrot could identify wool, paper, rock ? he had to LEARN
animals understand syntax?
dog walked to the girl.
two sentences contain EXACTLY the same words, but in a different order.
Because the words are in a different order, THE TWO SENTENCES HAVE
DIFFERENT MEANINGS. That is syntax (structure of the sentence) conveys MEANING.
The question in the dolphin study was whether dolphins could understand that the
ORDER of words (communicated in sign language) conveyed meaning. That is, could
the dolphins understand that the exact same words, arranged in two different
orders meant two different things. The answer was yes.
Skeptic: His opinion is that trial and error is the basis of all
animal learning (even though at the very beginning of the film he said that
trial and error learning could not explain the rat's use of mental maps.
one can deny that there are huge differences in what humans can do and what
other species can do. However, the Skeptic wants to draw a sharp line between
humans and other species. But the evidence presented in this film contradicts
demonstrated creative problem solving, could understand new words and even