Resting on a blade of tall grass. Fraser's Hill, Peninsular
Malaysia.
Clinging to the whitewashed wall of a colonial-era bungalow.
Fraser's Hill, Peninsular Malaysia.
Family : MICROHYLIDAE
Species : Metaphrynella pollicaris
Size (snout to vent) : Female 4.1 cm, Male 3.4 cm
References : H3, H4
Links :
Tree-hole frogs exploit resonance effects |
This small, microhylid
frog is more often heard than seen : the Treehole Frog adds its distinctive
call to the night-time sounds of Peninsular Malaysia's hill resorts such as
Fraser's Hill, Cameron Highlands or Maxwell Hill.
Males call from the inside of water-filled tree holes, particularly
favouring the interior of thick bamboo stems if available. Studies show they
are able to adjust the pitch of their simple piping call to
match the acoustic properties of their chosen hole, and the amount of water
with which it is filled, thus achieving a resonance which carries
their call a long distance. Thus, they 'play' their tree hole like a
woodwind musical instrument. On active nights, when males are
desperately trying to attract a female to their hole to mate, the overall
effect is of an evening chorus of random, but melodic 'peeps' and 'whoops'
from all directions in the forest.
Mating takes place inside the tree hole, where the eggs soon hatch to
tadpoles, which in turn metamorphose to young froglets. When ready, these
emerge as young adults from their confinement, presumably to go in search of
their own hole.
The Treehole Frog is attractively patterned with vague banding and mottled
patches of light brown, orange-brown, dark brown, fawn and cream. The head
is sometimes of darker brown. Its skin surface is rough.
Metaphrynella pollicaris is restricted to montane areas of Peninsular
Malaysia up to around 2000 metres elevation. A closely-related species, the
Bornean Treehole Frog Metaphrynella sundana, occurs in Borneo.
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