"Slanted" Eyes in Orientals

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Likewise a sexual preference that ends up causing lower surival rates is not long for survival either.

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I disagree with this. I think a lot of sexual selection decreases surivial, hell most of it might. It would only matter if the decrease in survival had a direct and significant effect on the ability to producve offspring. You also have the "sexy son" hypothesis going on which makes it very difficult to alter female preference once it is in full spring, add that to a red queen race I think you could concive of sexual selection that could destroy a species.[This message has been edited by Parsimonious_Razor, 04-19-2004]

I am not arguing the power of sexual selection I have spent the last two semesters studying nothing but sexually selected traits. I don't think you can say that people just lump any trait we don't have a survival benefit for into sexual selection. There are some pretty standard ways to look for SS in action. Opposite sex preference for the trait, increased mating success for exaggerating the trait, decreased success for eliminating or decreasing the trait, ect.Honest signaling by its very nature decreases the over all health of the organism. It’s costly and forces you to turn energy away from usually immune development and is a not a very efficient use of calories.I doubt that slanted eyes falls under any framework for honest signaling. Though I haven't specifically studied it I can't see how they are a large and costly signal. I think you could almost just classify it as an arbitrary variation. All the classic facial signals that have been identified in research as honest signals (facial symmetry, estronization/testosteronization) are present in every group of people. There hasn't been a sudden selection pressure for say directional asymmetry for the eyes in some group. But there is an almost infinite variety in which faces can be organized and still adhere to the basic signaling of Homo Sap. Most people find traits that belong to individuals they are around a lot more attractive than traits of individuals they do not see often. But what’s interesting about this is that after living with another group for a period of time you will get the attractiveness switch so that you are finding the new traits more and more attractive (though most people still rank the traits of where they were born and raised as always slightly more attractive). In short I don't think its sexually selected, I think its just an arbitrary variation or perhaps a byproduct of some other adaptation working on a different level.

Probably pretty close to splitting hairs. The limits to the attraction of novelty is based on species typical designs and high pheno/genotypic quality. You won't find six eyes attractive or a highly testoteronized face attractive on a female no matter where you have been raised. But there is an almost infinite subtly in the way a face can be put together with in these boundaries. Slanted eyes/open eyes being one example. If there is no adaptive benefit or signaling effect it becomes very difficult to argue for ANY selection pressure natural or sexual.The main point I was making about changes in how attractive you find new feature with in the boundaries as a function of how long you have been around them is that any of these traits fall naturally under the human spectrum of "attractive" and its just getting used to them. I can't remember the study off the top of my head, I will look for it. That looked at how attractiveness ratings for various facial features changed compared to frequency of exposure to the traits. If these traits are already with in the radar of human attractiveness then they are purely a historical accident as was said early on but not in terms of sexual selection. I don't think there is ANY selection going on here, but I could be proved wrong if someone had some more concrete data on what kind of signal could be being displayed here.

I will work on it tomarrow. Dr. Miller has done some interesting work, I took a course from him last semester and liked his theory quiet a bit. I think it lacks a certain falsifiablity for the moment, and personally have a tendancy to lean towards a slightly diffrent version of human intelligence (more in line with Randy Thornhill also at UNM).But I will try and post the article info tomarrow.

Okay the big tour de force for the commonality of what constitutes facial attractivness was:Michael R. Cunningham, Alan R. Roberts,Anita P. Barbee,Perri B. Druen, Cheng-Huan Wu "Their Ideas of Beauty Are, on the Whole, the Same as Ours: Consistency and Variability in the Cross-Cultural Perception of Female Physical Attractiveness " Journal of Personality and Social Psychology. Vol. 68 (2) February 1995, pp. 261-279. American Psychological AssociationI thought this study also showed that exposure to faces of diffrent races increased attractivness ratings, I was wroung. That information actually when I started e-mailing around was something I must have picked up in my conversations with on of my advisors. He said it was ancedotal but talked about but he couldn't think of a specific study. So I this is what I got. Sorry about that.I don't think that mix up harms my point that facial attractivness as a sexually selected signal stays pretty constant across cultures and that minor variations are insignificant and probably totally accidental and not under direct selection of any type.

In honest signaling you can take several approaches to it, the first is large exaggerated and costly signals that signify your general good health and ability to invest in such a gaudy display. The second is to try and recreate a very refined average. I have always found this analogous to say the difference between mocking bird mate calls and whale mate calls. The mocking bird trains very hard to have novel and loud and impressive calls, while the whale works very hard to try and replicate precisely songs that can be 4-6 hours long. Females choose either on gaudy display or the accuracy of replication. Facial attractiveness seems to be the latter type of signaling. The average of any amount of faces will always be the most attractive.Symmetry is very important and probably one of the greatest signals but another VERY important part of facial attractiveness is secondary hormone markers. For women the face needs to be highly estrgonized and in men it needs to be highly testosteronized (this is a bit of a misnomer since an estrognized face is a face that has not be testosteronized, since high estrogen to testosterone ratio prevents structural changes testosterone makes after puberty). Also factors such as neotany and senesance plays a role. The study I quoted above gives half a dozen or so important criteria.People do have a tendency to rank those of their same ethnic background as more attractive than other ethnic backgrounds. But when they rank the relative attractiveness of people in other ethnic backgrounds it correlates like r>.9 with the within ethnic ranks. Also there is talk that maybe exposure to novel ethnic traits over time will increase the relative attractiveness rankings. But I again I don't think this has been systematically studied.