Are humans still evolving?
I get the overall impression that most people think humans aren't evolving anymore, due to the way we care for our sick. I've been in classes where the question was thrown out there, and people just don't seem sure, or they think if it happens, it happens in 3rd world nations, not here.
When people do talk about evolution, they usually envision things such as, their great grandkid's grandkid's with larger brains, or some such thing that they see as an improvement.
I think this shows that people in general just don't understand how natural selection works.
First off, it works by killing.
It's not going to make your kids or great grandkid's smarter...it's going to either kill them, or not kill them. If they happen to be smarter or dumber, that may be a factor, or not.
Here's something else to think about: What is "natural"? And is natural better than man made?
One definition puts everything in the realm of nature. A great big ol' pool full of mercury is natural, aluminum cans are natural, everything is natural, because humans are part of nature. Further more, really horrible things can be natural; nightshade berries, drowning, viruses, sharks and lightning; all natural.
I have a different definition. Natural things, by my definition, are things human beings have been exposed to for many, many generations, and we've evolved to deal with.
We haven't evolved to deal with mercury, either in big ol' pools or in out water. It's in nature, it's been around longer than we have, but we just haven't run across it much. Lots of things are like that; twinkies, cigarettes, computers, etc.
Are all new things, by this definition, unnatural things, bad? No, but our genetic memory lacks the instincts to guide us.
If Cindy-Lou Hoo, dies of cancer at age two, that's natural selection in action.
Even if it isn't her fault...if her mother smoked a pack a day, until she found out she was pregnant.
Because somewhere, there is a mom to be who finds the oder cigarette smoke to be more nauseating than the oder of the old homeless guy on the bus.
This is random. We've evolved to find nightshade, and other such poisons and nasty substances we've been exposed to for many generations, to taste bitter, or smell disgusting, or look or feel repulsive. But things like cigs...some people love 'em, other's can't stand them. And things like pesticides, we can't even taste; while something we're used to as a species, like say, human blood, we can pick up at low concentrations like a few parts per million.
Most things we've dealt with for a long time, we've taken advantage of. Even things you might not expect... Earth's gravity is essential to certain molecules in our immune system. The magnetic field around Earth was vital to our emergence.
Our needs and frailties are more subtle than we know...likely more subtle than we will ever know.
On a personal note, our car broke when it leaked transmission fluid today; I walked a mile with Scott to deal with the problem, and it was bitterly cold out. This was in the late morning, and I still haven't been able to warm up from it. C'mon, Global Warming, don't slack off on me now!
When people do talk about evolution, they usually envision things such as, their great grandkid's grandkid's with larger brains, or some such thing that they see as an improvement.
I think this shows that people in general just don't understand how natural selection works.
First off, it works by killing.
It's not going to make your kids or great grandkid's smarter...it's going to either kill them, or not kill them. If they happen to be smarter or dumber, that may be a factor, or not.
Here's something else to think about: What is "natural"? And is natural better than man made?
One definition puts everything in the realm of nature. A great big ol' pool full of mercury is natural, aluminum cans are natural, everything is natural, because humans are part of nature. Further more, really horrible things can be natural; nightshade berries, drowning, viruses, sharks and lightning; all natural.
I have a different definition. Natural things, by my definition, are things human beings have been exposed to for many, many generations, and we've evolved to deal with.
We haven't evolved to deal with mercury, either in big ol' pools or in out water. It's in nature, it's been around longer than we have, but we just haven't run across it much. Lots of things are like that; twinkies, cigarettes, computers, etc.
Are all new things, by this definition, unnatural things, bad? No, but our genetic memory lacks the instincts to guide us.
If Cindy-Lou Hoo, dies of cancer at age two, that's natural selection in action.
Even if it isn't her fault...if her mother smoked a pack a day, until she found out she was pregnant.
Because somewhere, there is a mom to be who finds the oder cigarette smoke to be more nauseating than the oder of the old homeless guy on the bus.
This is random. We've evolved to find nightshade, and other such poisons and nasty substances we've been exposed to for many generations, to taste bitter, or smell disgusting, or look or feel repulsive. But things like cigs...some people love 'em, other's can't stand them. And things like pesticides, we can't even taste; while something we're used to as a species, like say, human blood, we can pick up at low concentrations like a few parts per million.
Most things we've dealt with for a long time, we've taken advantage of. Even things you might not expect... Earth's gravity is essential to certain molecules in our immune system. The magnetic field around Earth was vital to our emergence.
Our needs and frailties are more subtle than we know...likely more subtle than we will ever know.
On a personal note, our car broke when it leaked transmission fluid today; I walked a mile with Scott to deal with the problem, and it was bitterly cold out. This was in the late morning, and I still haven't been able to warm up from it. C'mon, Global Warming, don't slack off on me now!