‘ The evolution of a leaf-shaped tail seems to be a remarkably good survival strategy ....’
blends in perfectly with the lichens and mosses which encrust the trees or boulders upon which the lizards rest , and the dappled patterns of shadows cast by foliage . Secondly , the irregular contrasting markings serve to break-up the outline of the animals ; obliterating their form in a type of camouflage known as disruptive colouration . This strategy has been adopted by the military to camouflage soldiers , vehicles and hides ( and is now also very much in fashion as ‘ army print ’). Leaf-tailed geckos ’ bodies are rugose , with numerous small projections , and this adds authenticity to the creation of a lichenencrusted appearance . These lizards therefore appear to utilise two different categories of camouflage : crypsis , which consists of avoiding detection through matching the background and disrupting their outline ; and mimicry , in that they masquerade as inanimate objects such as bark ( without necessarily blending into the general background ). Leaf-tailed geckos are nocturnal ; they go about their business foraging , feeding , mating and doing whatever else geckos do under the cover of darkness . During the day they must rest , and potentially this can leave them exposed to predators . Thanks to their superb camouflage , they can successfully bluff diurnal predators such as birds , which rely primarily upon vision to detect prey items .
Like most other geckos , leaf-tails can also undergo caudal autotomy , or ‘ drop ’ their tails when seized by a predator . Once ‘ disengaged ’ the tail will continue to writhe , producing a distraction which will often afford the gecko an opportunity to scurry away . Tails are important for balance , and fortunately can be regenerated , however , regenerated tails tend to be somewhat different in both colour and pattern , and lack tubercles , having a distinctive smooth scalation . This disparity renders geckos with regrown tails less inconspicuous than those with original tails . Judging by the high incidence of leaf-tailed geckos with regenerated tails , it appears that despite their camouflage , they are nevertheless subject to substantial predation attempts : a study involving 92 P . platurus geckos found that 61 % of females and 79 % of males had regenerated tails – figures similar to those reported for other carphodactyline geckos . For P . platurus at least , many of
‘ The evolution of a leaf-shaped tail seems to be a remarkably good survival strategy ....’
these tail casualties are likely to be the result of cats , which are a major threat to native wildlife in Australia , in both urban and rural areas . Consequently , it is imperative that if people choose to have cats , they keep their pets indoors , or confine them to cat runs ( this is also beneficial to the felines themselves , since it is common for cats to be injured or killed on the roads ).
The evolution of a leaf-shaped or leaf-like tail in geckos seems to be a remarkably good survival strategy , as another lineage has independently developed this adaptation , in a case of convergent evolution . The scientist who came up with the generic name for the leaf-tailed geckos of Madagascar decided to go with a descriptive moniker , dubbing them Uroplatus , meaning ‘ flat tail ’ in Latin . Some are like their Australian counterparts , and appear to mimic moss rather than leaves , whilst others have evolved body shapes , colours and patterns that take the leaf masquerade to extremes . The most famous species , the Satanic
Leaf-tailed Gecko ( U . phantasticus ) even has leaf-like vein patterns running across its body , along with indentations in its tail that convincingly imitate parts of leaves that have rotted away - since , on the ground , dead dry leaves are seldom in perfect form !
Like most other geckos , Australia ’ s leaf-tails are nocturnal , with large eyes adapted to low-light conditions . They are sit-and-wait predators , and remain motionless while a prey item approaches , before lunging swiftly when it is within reach . They are not fussy eaters , and will consume a wide range of invertebrates , including chilopods ( millipedes and centipedes ), moths , crickets and beetles , although they do have a predilection for larger-bodied prey , such as spiders and cockroaches . They have even been reported to consume other smaller geckos , like the velvet gecko , Oedura lesueurii .
Reproduction is typically highly seasonal , with female leaf-tails undergoing vitellogenesis and ovulation in spring , and oviposition occurring in summer . Clutches generally consist of two oval-shaped eggs . Leaf-tailed geckos ( like lizards in general ) are terrible parents , and leave the eggs to develop unaided , so the baby geckos must start life from day one fending for themselves . However , the eggs are usually concealed in a small excavation that the female backfills with her hind legs . Female P . platurus have also been observed ( both in captivity and the wild ) rolling their eggs about in soil . The parchment-like shells are initially quite sticky , and thus soil particles adhere to the eggs , resulting in another form of camouflage ; this time as a product of instinctive behaviour rather than inherent form .
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