Saga Bjornor
8A
2/12/2014
Intelligence to Crow About
For years crows have been seen as “bird-brains”,
but they are not as dumb as they seem… studies have proven that they are highly
intelligent. Could their intelligence reveal an alternate evolutionary path to
intelligence?
November 28th, 2013 it
has been reported that neurobiologists Lena Veit and Professor Andreas Nieder
from Tubingen University have discovered Corvid’s (Jays, Magpies, Crows, and
Ravens) true intelligence. They have made a series of tests and observations
on trained crows to demonstrate their abilities. Crows are known for their
astonishing memory, remembering for years those people who have really annoyed
them. Jays also recall numerous hiding places and change their hiding places to
protect their stashes from theft. Corvids even adjust their behavior according to
the behaviors of other birds in their own species. Birds like Corvids are also
able to make and use tool just like primates. These results were very surprising
and impressive because a bird’s forebrain is much smaller than a mammal’s so in
the past researchers did not take bird intelligence as seriously as they should
have. Their intelligence stretch so far that behavioral biologists have even
called them “feathered primates”!
To demonstrate a crow’s intelligence Veit and
Nieder used two trained crows to perform a memory test on a computer. The birds
would be shown a picture that it would have to memorize, then the crow would be
shown two new pictures, one would be the same as the first one and the other
one different. The bird would get a cue that would vary the answer. If the cue
that the bird heard a high-pitched sound or saw a blue circle it was the cue
that the crow had to choose the picture that was the same as the original one.
If the crow heard a burst of white sound or saw a red circle it was a cue that
the crow had to choose the picture that was different for the original. The
crows did this pretty easily; they could perform at least as well as other
primates and even people! In primates the prefrontal cortex (PFC) has a big
role in the cerebral activities as it organizes sensory input and prioritizes what
to do about it. Though a bird’s cerebrum is proportionally smaller than mammal’s
it seemed that they were less intelligent, though now it is proven that they do
not need a large cerebrum to be intelligent! This is because they use a different
part of the brain to decide how to react and sort things. The nidopallium caudolaterale (NCL) is the birds “decision center”. Thought
mammals and birds have different brain anatomy the bird’s NCL and the mammalian
PFC develop from the same general region; researchers say PFC and NCL “evolved
from the same structure in a common ancestor”.
Yet the mammalian PFC and the bird NCL are very different when it comes
to their connections thought the brain and the overall architecture of the bird
and mammalian brain are very different. Yet researchers have come to the
conclusion that “ the avian NCL is considered to be a functional analogue of
the mammalian PFC, a structure with similar function but different evolutionary
origin” which basically mean that the PFC and NCL serve a similar purpose and
are built similarly yet they evolved differently.
This is a very important discover since this means that there
is another way to evolve to gain intelligence and that the pathway of evolved
intelligence in primates and in birds are different. Veit says “Many functions
are realized differently in birds because a long evolutionary history separates
us form these direct descendants of the dinosaurs. This means that bird brains
can show us an alternative solution out of how intelligent behavior is produced
with a different anatomy.”
Veit
and Nieder were also able to pinpoint which neurons were activated in the crow’s
brain when having to make a choice in the memory test. Certain neurons turned
on moments before the bird followed a “matching-cure” and a set of other
neurons where turned on moments before the bird followed a “non-matching-cue”.
They could see that when an error occurred it was because the bird turned on
the worn set of neurons. Yet even though the crows made some mistakes they were
still able to correctly answer more that 90% correctly at all times!
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