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[00:00.12]Using the term "bird brain" is one way to insult another person's intelligence.
[00:09.04]That is because a bird's brain is small.
[00:13.33]So, anyone with such a bird-sized brain was thought to be not that intelligent.
[00:22.76]But calling someone a bird brain might not be as insulting as it once was.
[00:30.52]That finding comes from a study of the mental abilities of birds.
[00:36.16]Two European scientists reported that at least two kinds of birds
[00:41.60]-- crows and parrots -- can think logically.
[00:48.60]A crow or parrot can recognize itself when the bird sees its image in a mirror.
[00:55.52]The scientists say crows and parrots also can feel empathy.
[01:01.16]In other words, they are able to understand
[01:04.40]and share the experiences and emotions of other birds.
[01:10.80]According to researchers, these abilities are "as sophisticated
[01:16.04]and diverse as those of apes."
[01:20.48]However, the brains of birds and those of apes are different.
[01:26.04]The brain of a bird does not have a neocortex.
[01:30.40]The neocortex controls thinking and remembering -- one's cognitive skills.
[01:39.08]A bird brain is also much smaller than the brain of a monkey or other ape.
[01:45.28]So how can birds perform as well as mammals in some activities?
[01:52.64]Researchers in Germany suggest that different methods of complex thinking
[01:58.72]developed independently in birds and mammals.
[02:03.64]The researchers found that the brains of birds and mammals do have different structures.
[02:11.64]But there are also similarities in the brain architecture.
[02:16.84]The brains of both creatures have what is called
[02:21.32]a pre-frontal structure that controls similar high-level functions.
[02:28.04]The researchers propose a separate path of development for the similarities.
[02:33.92]The reason: both species faced the same challenges for survival.
[02:41.32]The researchers noted that neither a multilayered cortex
[02:45.96]nor a big brain is required for complex mental skills.
[02:51.22]They reported their findings in the journal Trends in Cognitive Sciences.
[02:57.22]I'm Anna Matteo.
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