(Actually, I remember reading somewhere that SOME lizards can lay fertile eggs in the absence of a male which hatch out as males, to fill what nature perceives as a void, ie. an environment with females but no appropriate males) but I don't know whether cresteds can. But female cresteds do lay eggs with or without males, as chickens do without ever having seen a rooster, or female human beings, who shed an egg every month or so (until menopause) whether or not there is a male in the picture. Just nature's way of facilitating reproduction, I guess. I hope you are feeding the CGD so that there is enough calcium in their diets at least.
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Terri
5:9:5 crested geckos: Bear, Goldfish, Kermit, Brimstone, WildFire, Big Red, Olive, Smudge, Belle, Brilliant, Tina, Brick, Toni, Beauty, WildSpatter-Spots-to-Spare, Randi(y), Squeak, Tigersides prev. knwn as Pastel, & Bling. (last 3 just hatched)