Humans have crossover air and food pipes which enable us to have complex speech but also make the chance of choking much greater.
We also have a sharp ridge of bone on the inside of our skulls for no ther reason than it fits the contour of the brain, and it didn't used to caus problems when we were on the savannah but now that we can travel much faster on wheels of all sorts (bikes, cars), it causes a lot of damage to brains.
Re: Trying to steer the past sub-thread back on topic
quote:If most mutations are of this form of compromises or tradeoffs between something useful in the prevention of disease with some other form of disease,
But nobody except you has said that most beneficial mutations are like this.
For example, the CCR5 mutation.
Or any of the many, many, many mutations that make someone a little more disease resistant, a bit more attractive to mates, able to have a little bit easier time in childbirth, produce a little more viable sperm, are just a little more able to digest the most abundant local food source, able to produce just a bit more milk tofeed their young, have just slightly better reflexes to avoid being killed by that predator, etc.
I think it might be helpful for you to remember that for most of our evolutionary history, life was a daily struggle. It was very difficult to get enough food every day, there were no tetanus shots or antibiotics or doctors to stitch your wounds or set your broken bones or help you through a difficult pregnancy and childbirth or dentists to pull bad teeth.
A very small advantage would easily mean the difference between life and death in many cases. Or at least the life or death or the very creation of your offspring.
quote:I don't even see how you can get a viable population from Sickle Cell despite its protection against malaria,
Maleria kills babies.
Sickle Cell keeps malaria from killing the babies.
But anyway, Faith, if we didn't have a large, thriving, "viable" transcontinetal population of people with SCD, we wouldn't be having this conversation about SCD, would we?
You are also forgetting what I have told you before which is that one can be a carrier of the SCD mutation and be immune to malaria but be virtually asymptomatic.
quote:myself, for such a disease-ridden population to change further, let alone float the whole history of evolution. Sure if malaria leaves the environment then the sickle cell factor will become less frequent in the population. In other words you have to get rid of it to have a healthy population. How is that anything that could possibly further evolution?
As I've said before, evolution does not predict "healthy" populations.
It predicts change in response to environmental pressures.
Sometimes that means extinction. Actually, most of the time.
Let me ask you this...
Which is a "healthier" population;
One that is wiped out by maleria or one that numbers in the millions?
quote:The "overwhelming evidence" is an illusion. But there is no point in arguing this with a dozen people who are only going to use their numbers and their being on the side of the "right" opinion, plus ridicule, to win their point, instead of arguments, and who just can't bear it when we aren't persuaded.
Welcome to the rigors of scientific inquiry.
And nobody has used ridicule to win their point.
You handed all of us our points on a silver platter because you haven't addressed most of them with anything other than personal incredulity, and the rest you haven't addressed at all.
quote:But it is not anthropomorphizing anything to suspect that what is observed of what IS healthy could not possibly have come about by a system that pits disease against disease, and that calling that "beneficial" flies in the face of reason. Such a system is not a viable system even for survival let alone evolution.
Which is a more viable population;
One which is wiped out by malaria, or one that spans several continents and numbers in the millions?
Because if we don't work from a definition of "beneficial" before we attempt to give you examples, you can dismiss all of them as not meeting your idea of what "beneficial" means.
quote:It's fine for it to be recognized, and for the various mutations to be explored in its light, but when you impose it on me, require that I accept it, and treat my objections as simply a refusal to be scientific, you don't seem to recognize that all you are doing is absolutely pre-empting any possibility of having a different point of view about the very question we are discussing.
You can absolutely have a different point of view.
But this is a science thread.
All points of view need to be scientific here.
All claims and rebuttals need to have evidence-based backing.
All your terms need to be defined before you claim that they do not meet your definition.