Download Protective coloration of young leaves in certain

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NOTE
Protective Coloration of Young Leaves in Certain Malaysian Palms
In Malaysia, understory palms play an important role. Some
(Calamus, Daemonorops)
may eventually leave
( Oncosperma,
Orania). Still others remain permanently as comparatively short understory plants (Arenga hookeri, Nenga
macrocarpa, Pinanga spp., lguanura geonomaeformis, etc.). Most of the last-mentioned species are unarmed,
the understory by climbing; others grow up to assume a position very close to canopy level
lacking spines or thorns. I have noticed on many occasions that the young developing leaves of some species
of the last category, particularly
Iguanura
and
Pinanga,
are dull-colored because of the presence of both an­
thocyanins and chlorophyll, the reddish and green tints combining to form a dull brown. This color from a
distance strikingly mimics the drab color of dying or w ithered dead leaves. Such new leaves fail to show dam­
age from animal predation (at least in intact environments). For animals which rely on eyesight for the rec­
ognition of suitable food plants, these palms may apppear unsuitable, being comprised only of "dead" and
adult leaves. Is it possible that the young leaf coloration is adaptive in this regard, and therefore that the red
pigment is playing at least a dual, perhaps a triple, role-as a lignin precursor, as a photosynthesis enhancer,
and as a "dead-leaf color" mimic in conjunction with the green chlorophyll?
Benjamin C. Stone
Department of Botany
University of Malaya
Kuala Lumpur, Malaysia
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