Page 80 - Fish and Amphibians (Britannica Illustrated Science Library)
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76 AMPHIBIANS                                                                                                                                                                                          FISH AND AMPHIBIANS  77




          A Very Peculiar Tail                                                                                                                                      EYE
                                                                                                                                                                    Large and bulging,
                                                                                                                                                                    with a dark-brown iris
                                                                                                                                                                                                  Tongue pad
                he salamander is an animal of the order Urodela that needs damp places to survive. It lives
                in a very limited range of areas, and it is highly sensitive to modifications in its natural                                                                                                  The tongue
          T habitat. Unlike frogs and toads, the salamander keeps its tail when it reaches                                                                                                                    muscles retract.
          adulthood. The tail makes up nearly half the length of its body. Salamanders,
          especially adults, are completely nocturnal. Their movements are slow
          when they walk or crawl along the ground. During the day they stay
          hidden under rocks, in underground burrows, and on tree trunks.
                                                                                                                                                                                                              Outer section
                                                                                                                                                                                                              of the tongue

                                        HUMIDITY
                      COMMON            is necessary for                                                                                                                                                         Retractor
                      SALAMANDER        breathing                                                                                                                                                                muscles
                      Salamandra        through the skin.
                      salamandra
                                                                                                                                                                                                         Feeding Habits
          Habitat     Europe
                                                                                                                                                                                                         CWith its long tongue, the salamander can trap
          Order       Urodela
                                                                                                                                                                                                         its prey in a flash and quickly gulp it down. These
          Family      Salamandridae                                                                                                                                                                      carnivorous animals use mainly sight and smell to
                                                                                                                                                                                                         hunt. Because they are not very active,
                                                                                                                                                                                                         salamanders need relatively small amounts of
               7-11 inches                                                                                                                                                                               food. If they obtain more food than necessary,
               (18-28 cm)
                                                                                                                                                                                                         they store it as fat for lean times.


          Reproduction may
          occur in spring,
          depending on the
          habitat and the
          species.
                                                                                                                               Life Cycle
                                                                                                                               There are three stages to the life cycle: egg, larva,                        ITALIAN
           Anatomy                                                                                                             and adult. The eggs vary in size depending on the                            SALAMANDER
                                                                                                                               species. Larvae have feathery external gills.
           The head is narrow, with the mouth and                                                                              Metamorphosis lasts until adulthood, when
           eyes smaller than those of frogs and                                          SKIN                                  the salamander loses its gills and
           toads. However, in comparison with frogs  HEAD                                On the back and sides, the            switches to breathing with                                                  Defense
           and toads, the salamander's body is  Its head is smaller than                 skin is smooth and shiny.             lungs.                                            1  EGG
           longer, but its feet are similar in size and  those of frogs and toads        On the throat and belly,                                                                  Hatches into            The Italian spectacled salamander has two ways
                                                                                         the yellow spots are
           length. The salamander walks slowly,  because of the loss of                  duller and less numerous.                                                                 a larva                 of avoiding its enemies. It plays dead, or it curls
           never reaching great speeds, and its  bony structures and the                                                                                                                                   its tail forward. Other species defend themselves
           limbs are at a right angle to the body.  presence of cartilage.                                                                                                                                 by using a toxic substance produced by glands or
                                                                                                                                                                                                           by breaking off the tail, which continues to move
              TAIL                                                                                                                                                                                         on its own and confuses the predator.
              The salamander has
              a tail, unlike frogs
              and toads, which                                                                                                                                                            2  BIRTH
              lose their tails on                                                                                                                                                           The larva is born
              reaching adulthood.                                                                                                                        55 years                           with feathery
                                                                                                                                  ADULT                                                     external gills.
                                                                                                                               3
                                                                                                                                  Metamorphosis
                                                                                                                                  is completed;            LIFE SPAN OF SOME SPECIES
                                                                                                                                  the salamander
                                                                                                                                  reaches sexual
                           BODY
                                                                                                                                  maturity.
                           Long, with 16 to 22
                           thoracic vertebrae,                                                                                                                                                                          LARGE ALPINE
                           each one with a                                                                                                                                                                              SALAMANDER
                           pair of ribs.                                                                                                                                                                                Salamandra lanzai
                                                                             FEET                                                                                            LARVA                     38               is known for having
                                                                             Salamanders have four toes                                         CHANGE                       Metamorphosis begins;
                                                                             on each foot. The salamander                                       The body grows longer;                          months                  the longest gestational
                                                                             pushes its body forward by                                         the salamander begins        the salamander loses                       period of all animals,
                                                                             pressing against the ground.                                                                    its gills and switches                     even longer than that
                                                                                                                                                to breathe through the
                                                                                                                                                skin and lungs.              to breathing air.      GESTATIONAL PERIOD  of elephants.
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