This question came up during an interesting ignore-the-potholes chat with one of my seniors.
In a broad way or so to say a compressed way, evolution through the natural selection has been all about the ability to reproduce and survival. And every evolutionary step or speciation has been more or less associated with an easily observable and distinct change in the sense organ or the perception of senses. Speaking of sense organs, in humans the role of the olfactory sense has degraded a lot, in the sense that it does not help much in reproductive activities (as in lions) or in survival. So is the nose in the threat of being wiped out over time in human evolution?
Who knows, and why care I would say. Yet, our noses are quite useful still I would say I would have eaten quite a bit of rotten food in my time and got serious food poisoning in the process..
Nevertheless just one note evolution is not about survival, it is about reproduction and propagating genes (or more strictly inherited material), because reproductive success is often correlated with survival it is confusing, but there is no selection on survival per se.
Cheerio.
Genetic evolution in humans is (almost ) dead, memetic evolution took over. So, if ladies would prefer big noses in man, there would be genetic selection (driven by memes) to big noses (perhaps in both genders). This holds for almost every trait. Sexual selection is responsible for 90% of evolution (just my guess). Male offers, female selects.
http://www.frozenevolution.com/
http://www.google.cz/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&uact=8&ved=0CFYQFjAE&url=http%3A%2F%2Fweb.natur.cuni.cz%2Fflegr%2Ffrozen%2Freviewhall.pdf&ei=vgY8U_OoJqOG4ATbrYDQCw&usg=AFQjCNHRutqEFs2zzdej8mIyo2d_MAN9Xw&sig2=yngdhEX5jqn6h9x0cniusA
http://en.wikipedia.org/wiki/Memetic_evolution
http://en.wikipedia.org/wiki/Meme
Peter Cejchan how could you ever say that genetic evolution in humans is dead.. there is ample variation in reproductive succes and if one assumes a genetic component there selection..
Also your notions about sexual selection totally exclude the balancing force of natural selection and mutual choice which complicate things quite a bit.
"Is the nose in the threat of being wiped out over time in human evolution?"
-If by "nose" you mean "olfaction", it's "no".
-If you mean "external nose", it's "possibly yes".
If human ancestors had been scavengers or hunters on the open plains (as popular & outdated views of human evolution still believe) we had had an excellent sense of smell, but our poor olfaction is one of the many indications that Pleistocene Homo lived along coasts & rivers, collecting waterside & shallow aquatic foods, where they developed projecting nostrils (as many semi-aquatic mammals did) but didn't need a carnivore-like olfaction.
Since H.sapiens left the waterside & became +-fully terrestrial again, we may expect that our olfaction will improve gradually, and that the superfluous external nose will shrink further & possibly disappear.
Google, eg,
-unproven assumptions Verhaegen
-New Scientist lastword Oi, big nose!
https://groups.yahoo.com/neo/groups/AAT/conversations/topics/554
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