What are some real life examples of evolution/natural selection?

Question

*Other than: peppered moths and finches (most common if u search online)
*Pls. explain ur answer (don't jus give me da animal name)

Answer 1

Some brown bears moved north toward the polar regions. The darker the bear's hair, the harder time it had catching something to eat because it couldn't sneak across the white snow.

Lighter colored bears were more successful in hunting and passed on their lighter color to their more numerous offspring. Natural selection (survival of the most adept hunters) favored ever lighter colored bears.

The result is the polar bear. Polar bears and brown bears have been separated for about 20,000 years and are now considered separate species since they no longer interbreed.

Answer 2

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Answer 3

A very interesting question! My gut reaction was to agree with the others here, and say "Yes, natural selection would apply". But that's not necessarily the case. For natural selection to work, there are some criteria that must be met. One of the most critical is that mutations need to occur, and need to be both viable and fertile (that is, live and reproduce). This happens on earth partly because the DNA molecule is somewhat "flexible". If the wrong base happens to attach during replication, the DNA strand can stretch enough to accommodate the error, and continue to replicate. But it might also be possible for life to be based on a different chemistry. Perhaps a silicon-based life form would not be able to replicate if there was any error in replication (for example, because the molecular structure would be too rigid, and cause any error to "lock-up" the process of replication). In this case, all mutations would be fatal, and only perfect copies of the original could survive. There might be other possibilities as well; for example, an organism that has a truly minimal set of genes, so that every gene must replicate perfectly in order for the organism to survive. If this were the case, we might indeed find some alien species for which natural selection didn't apply. It would have to be a very simple organism, though, since it would never have the chance to evolve into something more complex. Evolution and natural selection DOES have some built-in assumptions (including both survivable mutations, and also some other factors such as competition for resources) If these assumptions aren't true, then evolution would either not apply, or create completely different results (and have completely different rules) than what we see on earth.

Answer 4

Uhm ... how about the flu virus. The only reason we need a new flu shot every year is that the world's flu viruses have evolved (through natural selection) to be immune to last year's flu shot.

Here's a list of not just evolution, but actual *speciation* observed in the lab or in nature:
http://www.talkorigins.org/faqs/speciation.html

Answer 5

The reason we keep needing new antibiotics is because the ones we have are only 99.9% efficient, so the remaining 0.1% (who are genetically immune because of mutation) breed int a whole new population of whichever bacteria. This is evolution in action.

(People who doubt evolution should not be permitted to use antibiotics other than penicillin!)

Answer 6

Melanin, a chemical that causes our iris eye color, freckles, tans and mahogany skin colors, musters to the surface of the skin to protect humans from fatal carcinogenic solar radiation. More solar radiation strikes the earth at the equator than at other global latitudes. The humans who originated close to the equator were more likely to survive if they had more melanin to protect them. Over time, those with more melanin and black skin survived.

Answer 7

how about you look up some info the role of bubonic plague and it's association with decreased HIV susceptibility in people of northeastern european decent?

another common example would be sickle cell anemia and malaria resistance...

=)

Answer 8

Giraffes & their long necks...