favoritenews777.wordpress.com/2008/06/06/lots-of-animal -
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Published on: 5/6/2008
Last Visited: 7/2/2008
"People thought insects were little robots doing everything by instinct," said Reuven Dukas, a biologist at McMaster University.
Research by Dr. Dukas and others has shown that insects deserve more respect.Dr. Dukas has found that the larvae of one of the all-time favorite lab animals, the fruit fly, Drosophila melanogaster, could learn to associate certain odors with food and other odors with predators.
In another set of experiments, Dr. Dukas discovered that young male flies wasted a lot of time trying to court unreceptive females.It takes time to learn the signs of a receptive fly.
Dr. Dukas hypothesizes that any animal with a nervous system can learn.Even in cases where scientists have failed to document learning in a species, he thinks they should not be too quick to rule it out."Is it because I'm not a good teacher or because the animal doesn't learn?"Dr. Dukas asked.
Although learning may be widespread among animals, Dr. Dukas wonders why they bothered to evolve it in the first place."You cannot just say that learning is an adaptation to a changing environment," he said.
It is possible to adapt to a changing environment without using a nervous system to learn.Bacteria can alter behavior to help their survival.If a microbe senses a toxin, it can swim away.If it senses a new food, it can switch genes on and off to alter its metabolism.
"A genetic network like the one in E. coli is amazingly good in changing environments," Dr. Dukas said.
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"We use computers with memory that's almost free, but biological information is costly," Dr. Dukas said.He added that the costs Dr. Kawecki documented were not smart animals' only penalties."It means you start out in life being inexperienced," Dr. Dukas said.
When birds leave the nest, they need time to learn to find food and avoid predators.As a result, they are more likely to starve or be killed.
Dr. Dukas argues that learning evolves to higher levels only when it is a better way to respond to the environment than relying on automatic responses.
"It's good when you want to rely on information that's unique to a time and place," Dr. Dukas said.Some bee species, for example, feed on a single flower species.
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Dr. Kawecki and Dr. Dukas agree that scientists need to pinpoint the tradeoffs, and they will have to gauge the role of learning in the lives of many species.
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"Humans have gone to the extreme," said Dr. Dukas, both in the ability of our species to learn and in the cost for that ability.
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The article also misspelled the name of the university where one of the researchers, Reuven Dukas, works as a biologist.
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