[Odonata-l] Sexual dimorphism question?

[Rob van Bemmelen]

errrr, before someone else points me at this: the fact that female-based 
polychromatism has not been found in many species, may show that my 
hypothesis may be less likely than Carlos' hypothesis with predation...

cheers, rob


>From: "Rob van Bemmelen" <ixobrychus at hotmail.com>
>To: mipilon at nrcan.gc.ca, odonata-l at listhost.ups.edu
>Subject: Re: [Odonata-l] Sexual dimorphism question?
>Date: Mon, 05 Feb 2007 05:26:37 -0500
>
>
>I have a little guess:
>Cryptic colored females may be less easily detected by males and thus less 
>often harassed.
>
>Female-based colour-polymorphism (or polychromatism), in which there is 
>always one male-like female, has been explained by frequency-dependent 
>advantage, as males only get to learn to recognize male-like females once 
>they become more abundant. This shows that the rare colourmorph is always 
>in advantage of the other. Thus, both a cryptic or a male-like appearance 
>have advantage(s).
>
>However, this does not explain the bright coloration of males......
>
>I hope somebody else has a better answer...
>
>Cheers, Rob
>
>
>
>
>>From: "Pilon, Michel" <mipilon at nrcan.gc.ca>
>>To: <odonata-l at listhost.ups.edu>
>>Subject: [Odonata-l] Sexual dimorphism question?
>>Date: Sun, 4 Feb 2007 16:10:23 -0500
>>
>>Hello again,
>>
>>I hope I don't annoy all of you with my naive questions...
>>
>>After reading the answers about my id's request and considering that in 
>>both case the sexual dimorphism is important, I would like to ask you the 
>>following question which came to my mind:
>>
>>What justify that sexual dimorphism amongst dragonflies...?
>>
>>With birds we know that the female is attracted by the colorful male and 
>>that she has to be duller because she has to lay over the eggs and should 
>>not be seen by predators...
>>
>>Is it the same thing amongst Odonata? Does the female attracted by the 
>>male colors? And why usually are they duller than the male? (I'm thinking 
>>also of Sympetrum obtrusum (white-faced Meadowhawk))
>>
>>Excuse-me again for my maybe so naive question...
>>
>>Michel Pilon
>>Sherbrooke
>>Quebec Canada
>>
>>Mes Parcours Nature:
>>http://parcours.pilonm.org
>>
>>_______________________________________________
>>Odonata-l mailing list
>>Odonata-l at listhost.ups.edu
>>https://mailweb.ups.edu/mailman/listinfo/odonata-l
>
>_________________________________________________________________
>Check out all that glitters with the MSN Entertainment Guide to the Academy 
>Awards®   http://movies.msn.com/movies/oscars2007/?icid=ncoscartagline2
>


>_______________________________________________
>Odonata-l mailing list
>Odonata-l at listhost.ups.edu
>https://mailweb.ups.edu/mailman/listinfo/odonata-l

_________________________________________________________________
Valentine’s Day -- Shop for gifts that spell L-O-V-E at MSN Shopping 
http://shopping.msn.com/content/shp/?ctId=8323,ptnrid=37,ptnrdata=24095&tcode=wlmtagline