Page 56 - Amphibian

DISAPPEARING ACT
The Spanish spadefoot toad gets Earth movers
its name from the black, horny
“spades” on its feet, which it uses
to dig feet first into sand or soft
earth. It can shuffle its feet
alternately to dig vertical burrows. Life on the surface is full of danger for amphi-
bians – of being eaten by predators, of drying out
(especially in the sun), and of starvation if too
much energy is spent chasing too little food.
Spade foot
Camouflage helps reduce the risk of being seen by
UNDERCOVER AGENT predators; hiding under cover reduces water loss;
1 This Asian bullfrog is and keeping still helps limit weight loss. Most
fairly typical in its habit
of moving backward amphibians can dig into leaf litter or into the
into cover.
Hiding reduces upper layers of the soil, and so solve all three
the likelihood problems at once. Some go one step further and
of being eaten or of
drying out, but most of dig way in, leaving just the head showing or
all it is a means of disappearing from sight altogether. They may
increasing the camouflage
effect while lying burrow to avoid cold or heat. Amphibian burrows
in wait for may be simple short tunnels under logs or rocks,
passing food.
or a vertical shaft filled with loose earth, ending in
an open chamber. More complex tunnels can be
over 25 ft (8 m) long, with separate chambers,
entrances, and exits, to keep out snakes, shrews,
and rats. Burrowers and nonburrowers alike use
ready-made burrows, and share their underground
homes with other animals (pp. 58–59).

GOING …
3The frog continues to bed itself into
the litter, helping to cover its shape. It GOING …
may pause at times to see how 4The back legs
comfortable it is. have disappeared.
Now the front legs
push back and forth
in the leaf litter,
making small pieces
of leaves move over
the body.

MOVING BACK
2 The color pattern on the frog’s back is very
similar to that of the mosses and leaf litter of its
surroundings. A shuffling movement of the back
feet takes it backward, down into the litter.

ODD TOAD OUT
This burrowing toad
from Mexico is a feet-first Most of the
burrower, like the spadefoot toad (above), frog is still
but it is so different from all other frogs and visible
toads that it has been placed in a family on its own.

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