http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/ Mon, 26 Nov 2012 12:00:51 +0000 hourly 1 http://wordpress.org/?v=3.4.2 http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3741 heather sf Sun, 14 Jun 2009 18:00:24 +0000 http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3741 What a great article! I have just read this out loud with my mother, and she would like to offer the "yolk blankie" hypothesis. The extra yolk in the eggs insulates the embryo from colder conditions, allowing it to develop as female. She is insistent on this, despite the potential evidence against it from the silicon tests/yolk from smaller eggs. She posits that the yolk from smaller eggs is thinner, perhaps the yolk from male eggs suffers from shrinkage in the cold weather. Silicon is potentially a different consistency in terms of blankie-like thermal retention. Yolk-blankie. Heard it here first. What a great article!
I have just read this out loud with my mother, and she would like to offer the “yolk blankie” hypothesis. The extra yolk in the eggs insulates the embryo from colder conditions, allowing it to develop as female. She is insistent on this, despite the potential evidence against it from the silicon tests/yolk from smaller eggs. She posits that the yolk from smaller eggs is thinner, perhaps the yolk from male eggs suffers from shrinkage in the cold weather. Silicon is potentially a different consistency in terms of blankie-like thermal retention. Yolk-blankie. Heard it here first.

]]> http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3740 Lab Rat Sun, 07 Jun 2009 12:07:43 +0000 http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3740 omg - i hate to break the scientific sort of atmosphere but I swear I first read the title as "Shrinks get their sex in three ways" I was very confused... Great aricle as always :D omg – i hate to break the scientific sort of atmosphere but I swear I first read the title as “Shrinks get their sex in three ways”
I was very confused…
Great aricle as always

]]> http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3739 AK Fri, 05 Jun 2009 15:24:32 +0000 http://blogs.discovermagazine.com/notrocketscience/2009/06/05/skinks-set-their-sex-in-three-ways-genes-temperature-and-egg-size/#comment-3739 One possibility is that more successful mothers, who can lay bigger eggs, are likely to be present when there is more food, and more females will represent a faster population growth to take advantage. Under cold circumstances, <b>or</b> when mothers are less successful, food is probably more scarce, and a higher proportion of the total population can be expected to die off. Under these circumstances, mothers are probably better off having lots of sons, since even one survivor might well propagate many of her genes than a bunch of daughters (most of which die). The relation between egg size and sex may actually be maternal: when maternal conditions indicate a preference for daughters, some (many) eggs are selected (by the mother's body) for daughters and hormonal changes and greater size are <b>both</b> applied (independently). The larger egg size will not only help the neonatal females survive, but presumably speed their advance to sexual (reproductive) maturity. Another possibility is that the small size of eggs targeted to be male may be a form of "handicap": if they prosper and reproduce despite the handicap they have demonstrated greater genetic superiority. One possibility is that more successful mothers, who can lay bigger eggs, are likely to be present when there is more food, and more females will represent a faster population growth to take advantage.
Under cold circumstances, or when mothers are less successful, food is probably more scarce, and a higher proportion of the total population can be expected to die off. Under these circumstances, mothers are probably better off having lots of sons, since even one survivor might well propagate many of her genes than a bunch of daughters (most of which die).
The relation between egg size and sex may actually be maternal: when maternal conditions indicate a preference for daughters, some (many) eggs are selected (by the mother’s body) for daughters and hormonal changes and greater size are both applied (independently). The larger egg size will not only help the neonatal females survive, but presumably speed their advance to sexual (reproductive) maturity.
Another possibility is that the small size of eggs targeted to be male may be a form of “handicap”: if they prosper and reproduce despite the handicap they have demonstrated greater genetic superiority.

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