Page 41 - Amphibian

Tadpole’s tail is
longer than Four newly
its body hatched
tadpoles
Tail of
tadpole

Gills

Tadpole Mouth JUST HATCHED
Tail still swims by 3After hatching, the tadpole feeds on
very long wriggling the remaining yolk in its gut. Its tail,
its long tail mouth, and external gills are poorly
developed. The tadpole attaches itself
to weeds, using two adhesive organs
behind its mouth and above its belly.
At seven to ten days, it begins to feed
on algae and swim actively.
FROM SIX TO
5NINE WEEKS
Between six and nine
weeks, the hind legs Underside of
appear as short buds. Coiled gut four-week-
At six weeks, the body old tadpole
becomes longer and the head
region becomes more distinct as the
tadpole grows older. In this tadpole,
the hind legs are functional and aid the
tail in propelling the tadpole forward. Its
diet may now include dead insects – even
dead tadpoles – as well as plants. The
bulges in the body are produced by the
developing front legs, which
emerge elbow-first through
openings in the body wall.

Half-tadpole, half-frog,
between six and nine weeks

AFTER NINE-WEEKS-OLD Row
6The tadpole now looks more like a miniature of tiny
frog with a long tail. The scars around the front legs Hind leg teeth
show where they emerged through the body wall. helps propel
The tail is gradually absorbed, and the froglets tadpole
begin to gather around the edges of the pond. forward AT FOUR WEEKS
4The external gills become
covered by skin, then
Bulge where gradually disappear, and are
front leg replaced by internal gills. The
will start tadpoles feed by using rows of
to form tiny teeth to rasp away at
plants or algae-covered
surfaces. This scraping
produces a “soup” of vegetable
Head starting particles which are trapped in
to take shape the mouth. The oxygenated,
food-laden water enters the
mouth and, after processing,
leaves by the spiracle. Four-
week-old tadpoles have a long,
coiled gut to extract as much
nourishment as possible from
their poor diet. They are
active social animals and
sometimes school
like fish.
Tail gradually
growing shorter
Front leg
now fully Tadpole between nine
formed and twelve weeks of age

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