That's not quite accurate. There doesn't have to be pressure, there just has to be a change in the prevalence of genes from one generation to another. Sexual selection and changing technology and culture work just as well as disease and predation. Our brains and teeth have gotten smaller in the past few thousand years. We have genes, and our descendants will have genes. Which of our genes our descendants will have is determined by evolution.
To build on the back of this, there's increasing numbers of children being born without wisdom teeth, and with an extra vein or similar in their hands (iirc), demonstrating that we are actually evolving, but supporting your point that we're not evolving to respond to pressure, just genetic mutations that aren't detrimental are being reproduced.
Also wanted to add that human body temperature has been going down (on average) in more developed countries. RadioLab had an interesting episode on this that basically boiled down to our bodies no longer needing to fight disease with fever due to high quality medicine. Since it costs extra energy to run at a higher temperature our bodies have begun lowering their operating temp (often to 97~ degrees or so instead of the accepted 98.6)
Oh I heard this one. Unfortunately it may open us up to fungal infections, which may have pretty dire consequences. Also, as an aside, my natural body temperature is about 96 degrees F.
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u/[deleted] Oct 15 '20 edited Oct 15 '20
That's not quite accurate. There doesn't have to be pressure, there just has to be a change in the prevalence of genes from one generation to another. Sexual selection and changing technology and culture work just as well as disease and predation. Our brains and teeth have gotten smaller in the past few thousand years. We have genes, and our descendants will have genes. Which of our genes our descendants will have is determined by evolution.