Autotomy, Tail Regeneration and Jumping ability in Cape Dwarf Geckos (Lygodactylus capensis) (Gekkonidae)

Abstract

Many studies have examined the effect of caudal autotomy on speed and behaviour of lizards escaping over horizontal surfaces, but there have been few studies on lizards escaping over vertical surfaces and, in particular, species that jump between surfaces. We examined jumping by the Cape dwarf gecko (Lygodactylus capensis) in terms of individuals' varying states of tail autotomy and regeneration. Although longer jumps were less likely to be successful (i.e. the animal would not successfully grip the surface and fell to the ground), there was no difference in the distance over which animals with full and partial tails would attempt to jump. Both recently autotomized individuals and individuals with intact tails successfully jumped up to nine times their body length (snout-vent length). The jumping ability of L. capensis was therefore clearly not negatively impaired by tail loss, presumably because the geckos are using their hind legs to propel their jump. Their tails may, however, be important to control their landing as well as their locomotion on vertical surfaces. The high observed frequency of tail loss, coupled with rapid and complete regeneration (including the scansorial tail tip), suggests that caudal autotomy is an important survival tactic in this species.

The Impact of Tail Loss on Stability during Jumping in Green Anoles (Anolis carolinensis)

“…Second, typical measures of jump performance, including takeoff velocity (mean p cm/s before tail loss vs. 124 ‫ע‬ 14 cm/s after tail loss) and jump distance (mean p 124 ‫ע‬ 21 cm/s before tail loss vs. cm/s after tail loss), were 21 ‫ע‬ 3 2 1 ‫ע‬ 5 not affected by autotomy. Maintaining jump distance despite tail loss has also recently been shown in the Cape dwarf gecko Lygodactylus capensis (Fleming and Bateman 2012). Finally, individuals varied with respect to their in-air stability during jumping after tail loss.…”

Telling Tails: Selective Pressures Acting on Investment in Lizard Tails

“…Although loss of even an unspecialized tail incurs costs for most lizards studied (Bateman and Fleming 2009), if the tail performs a specialized function that significantly increases survivorship (e.g., increases mobility when climbing, jumping, etc. ; Brown et al 1995;Medger et al 2008;Fleming et al 2009;Gillis et al 2009;Fleming and Bateman 2012), then, even if it regenerates to full function, loss of the tail can compromise survival while it is growing back. We therefore predict more caudal autotomy and longer tails for species that have unspecialized tails.…”

Re-regeneration to reduce negative effects associated with tail loss in lizards

“…Losing a tail comes with costs, although these are less severe than being killed by a predator. These costs, whether they be to locomotion 12,31,32 , anti-predation behaviour 33,34 or even to social status 35 , can be minimised through regeneration of the tail. Here, we have presented unequivocal evidence, through micro CT, that further regeneration of tail tissue is possible if a lizard loses part of the regenerated tail, something has only been anecdotal before 9,23,24 .…”