Harmless nectar source or deadly trap:Nepenthespitchers are activated by rain, condensation and nectar

Proceedings of the Royal Society B: Biological Sciences - Tập 275 Số 1632 - Trang 259-265 - 2008
Ulrike Bauer1,2, Holger F. Bohn1,3, Walter Federle1
1Department of Zoology, University of CambridgeDowning Street, Cambridge CB2 3EJ, UK
2Ulrike Bauer Google Scholar Find this author on PubMed
3Holger F Bohn Google Scholar Find this author on PubMed

Tóm tắt

The leaves ofNepenthespitcher plants are specialized pitfall traps which capture and digest arthropod prey. In many species, insects become trapped by ‘aquaplaning’ on the wet pitcher rim (peristome). Here we investigate the ecological implications of this capture mechanism inNepenthes rafflesianavar.typica. We combine meteorological data and continuous field measurements of peristome wetness using electrical conductance with experimental assessments of the pitchers' capture efficiency. Our results demonstrate that pitchers can be highly effective traps with capture rates as high as 80% but completely ineffective at other times. These dramatic changes are due to the wetting condition of the peristome. Variation of peristome wetness and capture efficiency was perfectly synchronous, and caused by rain, condensation and nectar secreted from peristome nectaries. The presence of nectar on the peristome increased surface wetness mainly indirectly by its hygroscopic properties. Experiments confirmed that pitchers with removed peristome nectaries remained generally drier and captured prey less efficiently than untreated controls. This role of nectar in prey capture represents a novel function of plant nectar. We propose that the intermittent and unpredictable activation ofNepenthespitcher traps facilitates ant recruitment and constitutes a strategy to maximize prey capture.

Từ khóa


Tài liệu tham khảo

Barbosa P. & Castellanos I. (eds) 2005 Ecology of predator–prey interactions Oxford UK: Oxford University Press.

10.1073/pnas.0405885101

10.2307/2425436

10.1021/ie50152a012

10.1017/S0266467400009160

Clarke C& Wong K.M Nepenthes of Borneo. 1997 Kota Kinabalu Malaysia:Natural History Publications.

10.1674/0003-0031(2000)144[0123:DVOSAI]2.0.CO;2

Driver P& Humphries N Protean behavior: the biology of unpredictability. 1988 Oxford UK:Oxford University Press.

Elias T.S, 1983, The biology of nectaries, 174

10.1016/S0169-5347(01)02269-8

10.1046/j.1469-8137.2002.00530.x

10.1242/jeb.01939

Herrera C. M. & Pellmyr O. (eds) 2002 Plant–animal interactions: an evolutionary approach Oxford UK: Blackwell Science Ltd.

Hölldobler B& Wilson E.O The ants. 1990 Cambridge MA:Belknap Press.

Jebb M, 1991, An account of Nepenthes in New Guinea, Sci. New Guinea, 17, 7

Jebb M, 1997, A skeletal revision of Nepenthes (Nepenthaceae), Blumea, 42, 1

Juniper B.E, 1962, How pitcher plants trap insects, New Sci, 13, 75

Juniper B.E Robins R.J& Joel D.M The carnivorous plants. 1989 London UK; San Diego CA:Academic Press.

10.1007/s704-002-8211-5

Knoll F, 1914, Über die Ursache des Ausgleitens der Insektenbeine an wachsbedeckten Pflanzenteilen, Jahr. Wiss. Bot, 54, 448

Krebs J.R& Davies N.B Behavioural ecology: an evolutionary approach. 1997 Oxford UK:Blackwell.

Lloyd F.E, 1942, Chronica botanica

10.1016/S0367-2530(17)30030-0

Merbach M.A, 2007, Why a carnivorous plant cooperates with an ant—selective defense against pitcher-destroying weevils in the myrmecophytic pitcher plant Nepenthes bicalcarata Hook. F, Ecotropica, 13, 45

10.2307/2261474

10.1006/anbo.1999.0857

10.2307/2656921

10.2307/2389076

10.1126/science.236.4804.964

Tan H. T. W. (ed.) 1997 A guide to the carnivorous plants of Singapore Singapore: Singapore Science Centre.

Wäckers F. L. van Rijn P. C. J. & Bruin J. (eds) 2005 Plant-provided food for carnivorous insects: protective mutualism and its applications Cambridge UK: Cambridge University Press.

Thông tin
Thông tin xuất bản

Proceedings of the Royal Society B: Biological Sciences

Tập 275 Số 1632

259-265

Thông tin tác giả