Page 57 - Reptiles & Dinosaurs (Britannica Illustrated Science Library)
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52 LIZARDS AND CROCODILES




 Geckos                                                           Scaly Eyes

                                                                  Unlike most lizards, geckos do not
                                                                  have movable eyelids. Their eyes
 eckos are a group of small, slender lizard species that live mostly  are covered with a transparent
 in tropical and subtropical regions and on many islands in the   membrane that they shed
                                                                  periodically, along with the rest of
 G oceans. Some species live in deserts, and many have burrows or  their skin.
 make their homes in rock crevices. They are nocturnal and can flee  A gecko's skin
 from their predators by voluntarily shedding their tails. Geckos are  is covered with
 the only lizards whose males produce sounds to attract females and  tiny scales.  Using its long, sticky
 to defend their territory. These agile climbers can walk on smooth  tongue, the gecko
                                                                  cleans the membrane
 vertical surfaces or even upside down by using tiny hairs on their feet  over its eyes and
 that let them stick to anything they touch.                      keeps it free of dust.

                                                                  Geckos cannot blink.
                                                                  They have only a fixed
 Leaf-Tailed Gecko  1,050                                         lens, with an iris that
                                                                  enlarges in darkness.
 When hanging by its tail, it looks exactly
 like a leaf, which gave rise to its common  SPECIES ARE IN                       Toes with Suckers
 name. Male geckos can produce sounds  THE GECKO FAMILY                           A gecko's feet end in toes surrounded by smooth
 similar to vocalized calls. In this species,                                     membranes. They have 20 to 23 adhesive pads
 they are especially loud and high-pitched.                                       on the underside of the fourth toe. Geckos can
                                                                                  climb directly upward and cling to smooth
                                                                                  surfaces, because each toe has a disc with
                                                                                  tightly packed concave areas that act as suckers.




 10 inches (25 cm)
 LEAF-TAILED GECKO  The texture of
             its skin helps it
 Scientific name  Uroplatus henkeli
 Its tail is  to blend into its
 Family  Gekkonidae  autotomic,  environment.
 Habitat  Trees  meaning that the
 gecko can shed                                                                  SETAE             SPATULAE
 Range  Madagascar, Africa  it, allowing the                                     Geckos have tiny  Each seta ends in up
 Diet  Carnivorous (insects)  reptile to double                                  filaments on the ends of  to 1,000 microscopic
 its speed.                                                                      their toes called setae.  hairs called spatulae.

 Flight of the Gecko                                                             Claw
 Its muscular legs
 The Kuhl's flying gecko lives in trees in  are those of a
 Southeast Asia. Unlike flying lizards, it  great climber.
 glides with its webbed feet. When it is
 not “flying,” it spends most of its time  A Rare Phenomenon
 hanging head down in the trees, ready             2 million                  Rows of
 for a rapid takeoff.  Scientists have explained the gecko's                  Setae
                 capacity to cling (which even enables them  THE NUMBER OF HAIRS
                 to climb glass and never get it dirty)  (SETAE) ON A GECKO'S
                 through electrostatic principles and even  FEET
                 microphysics.










 Spreading Its Limbs  Arching Its Back  Toes Backward  Touch Down   Tiny Pieces  Raising the Palm
 A  B                           and Support
 The membranes between  The membranes along its  When walking, it  generate the same  at a 30° angle
 its toes are used as wings  sides and flat tail help it to  moves them this way  The spatulae are very  force that draws  breaks this
 for gliding.  regulate its fall.  up to 15 times per  close to each other  molecules together.  attractive force.
                 second.        and to the surface.
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