Page 25 - Amphibian

DELICATE FINGERS
Surinam toads from eastern and northern parts of
South America spend their entire lives in water.
They have long, thin, tubular fingers, which
they use for catching and manipulating prey
toward the mouth when feeding. The tips of
the fingers are star-shaped and have a cluster
of smooth, fine filaments arranged in
branched pairs. The fingers themselves are (1) Vertical pupil of
covered in tiny spines which help the adult to red-eyed tree frog
grip slimy prey, like fish. The star-shaped tips
are only fully developed in adults and are
different in related species.

TEMPERATURE CONTROL
Amphibians rapidly lose body water by
evaporation in hot or dry conditions. They (2) Heart-shaped pupil of
can sense temperature levels and Oriental fire-bellied toad
sudden dryness through their skin,
and they control their body
temperature by basking in the sun if
too cold or retreating into the shade if
too hot. This painted reed frog from
South Africa is reducing the area of
its body surface exposed to the sun
by tucking in its front and hind legs. PERFECT PUPILS
Eye color and pupil shape are very
variable in frogs: (1) vertical, catlike for night vision
or quick response to rapidly changing light (3) Horizontal pupil
conditions; (2) heart-shaped; (3) horizontal, the of Asian tree toad
more common pupil for normal daylight vision;
and (4) round – newts and salamanders also
have round pupils.

Ear of
American
bullfrog
(4) Round pupil
of Madagascan
tomato frog

BIG EARS
Hearing is one of

the most important
senses in frogs. The size
of and distance between
the ears are related to the
wavelength and frequency of
the sound of the male’s call.
THE SWEET SMELL OF LOVE
Newts have an elaborate courtship
behaviour, during which the male
releases chemicals called “pheromones”
from the bulbous cloacal gland at
the base of his tail. He uses his
tail to waft these secretions
towards the female.

23