View previous topic | View next topic

Gynandromorphs

Page 1 of 1

Oceans Edge
979762.  Fri Mar 08, 2013 12:07 pm Reply with quote

An animal that exhibits both female and male sexual characteristics.

In some birds like Cardinals different sexes are differently coloured, each half of the bird is a different shade.



Quote:
... But in birds, unlike flies (or humans), the females are heterogametic: i.e., their sex chromosomes are different (the females are called ZW; and the males are ZZ). Iím not sure whether chromosome loss is involved in the production of this cardinal, or how that loss affects sex determination in birds (in humans, for example, unlike flies, the Y chromosome is important, so XO individuals are not phenotypic males but largely phenotypic females). An article at Live Science on a similar gynandromorph cardinal in Texas offers the following theory, based on the observation that in gynandromorph chickens the female side is the normal ZW and the male side the normal ZZ:

Itís not known exactly how gynandromorphy happens in birds, Arnold said. The predominant theory is that an error occurs in the formation of an egg, which normally carries one chromosome to unite with the single chromosome carried by the sperm. But if an egg accidentally ends up with two chromosomes ó a Z and a W ó and if this aberrant egg is fertilized by two Z-carrying sperm, the bird that results will have some ZZ cells and some ZW cells, he explained.

That seems unlikely to me because it requires the concatenation of two rare events: an egg carrying two sex chromosomes instead of one (but the normal half complement of autosomes), uniting not with one sperm but with two.


(From the Why Evolution Is True blog - for more more discussion on the phenomenon - you can read the article here)

 
AlmondFacialBar
979795.  Fri Mar 08, 2013 2:30 pm Reply with quote

Like the chicken on the Girls and Boys episode:


:-)

AlmondFacialBar


Last edited by AlmondFacialBar on Fri Mar 08, 2013 3:46 pm; edited 2 times in total

 
Efros
979826.  Fri Mar 08, 2013 3:32 pm Reply with quote

Nice article here about it.

 
TaoistYang
1317516.  Sun Mar 24, 2019 3:45 am Reply with quote

Bilateral Gynandromorphism!
https://futurism.com/beautiful-genetics-bilateral-gynandromorphs

Chimerism or Mosaic?
http://biologicalexceptions.blogspot.com/2015/09/when-youre-not-just-yourself.html

 

Page 1 of 1

All times are GMT - 5 Hours


Display posts from previous:   

Search Search Forums

Powered by phpBB © 2001, 2002 phpBB Group