Quoted from Rhacodactylus
by Philippe de Vosjoli-Frank fast and Allen Repashy-
From the Disease section of that book
"Mostly in gargoyle and crested geckos, a number of factors can lead to what is called "Floppy-Tail Syndrome" :the tail flops to the side or over the back when resting vertically in a head down position
In addition to the abnormal position of the tail-the pelvic girdle is also deformed and may become twisted in the direction of the tail
In case you are wondering whether this is a syndrome only found in captive animals-we can confirm that this pelvic deformity associated with floppy tail can also be found in wild crested geckos
The causes of this syndrome appear to be two-fold
The bones that make up the pelvic girdle are so thin that even a slight calcium deficiency can lead them to bend if subjected to pressure
In addition a long relatively heavy tail can,depending on the geckos position,exert pressure that can cause the thin zygapophyses that interconnect the vertebrae to bend or break at the base of the tail
Possibly a genetic factor involving a weakened pelvic girdle noticeable by a marked depression between the ilial bones on the upper surface of the pelvic area ,may contribute to the propensity for floppy tail
It is worth knowing that a mid dorsal depression of the pelvic area is common in a significant percentage of Rhacodactylus both in the wild and in captivity"
The more that I read on the function of their tails -to me it seems that they are most needed in infant to juvie stages and when they become adult size -there is less of a need for the prehensile attribute of this appendage and also a larger size may deemphasize the need for dropping their tails as a distraction for escape from predators
There has to be a reason that their tails are not regenerated as in other species of geckos and that so many adults are found "tailless" in the wild
just my 2 cents
Sandy
PS-I love my new book
