School of Science, Monash University Sunway Campus, Jalan Lagoon Selatan, 46150 Bandar Sunway, Selangor, Malaysia.
New Phytol. 2010 Apr;186(2):461-70. doi: 10.1111/j.1469-8137.2009.03166.x. Epub 2010 Jan 22.
*Three Bornean pitcher plant species, Nepenthes lowii, N. rajah and N. macrophylla, produce modified pitchers that 'capture' tree shrew faeces for nutritional benefit. Tree shrews (Tupaia montana) feed on exudates produced by glands on the inner surfaces of the pitcher lids and defecate into the pitchers. *Here, we tested the hypothesis that pitcher geometry in these species is related to tree shrew body size by comparing the pitcher characteristics with those of five other 'typical' (arthropod-trapping) Nepenthes species. *We found that only pitchers with large orifices and lids that are concave, elongated and oriented approximately at right angles to the orifice capture faeces. The distance from the tree shrews' food source (that is, the lid nectar glands) to the front of the pitcher orifice precisely matches the head plus body length of T. montana in the faeces-trapping species, and is a function of orifice size and the angle of lid reflexion. *Substantial changes to nutrient acquisition strategies in carnivorous plants may occur through simple modifications to trap geometry. This extraordinary plant-animal interaction adds to a growing body of evidence that Nepenthes represents a candidate model for adaptive radiation with regard to nitrogen sequestration strategies.
三种婆罗洲猪笼草物种，Nepenthes lowii、N. rajah 和 N. macrophylla，会产生改良的猪笼，以获取树鼩粪便中的营养物质。树鼩（Tupaia montana）以猪笼盖内表面腺体分泌的渗出物为食，并将粪便排入猪笼中。在这里，我们通过比较这些物种的猪笼特征与其他五种“典型”（捕食节肢动物）猪笼草物种，检验了这些物种的猪笼几何形状与树鼩体型相关的假说。我们发现，只有具有大开口和凹形、拉长且大致垂直于开口方向的盖子的猪笼才能捕获粪便。从树鼩的食物来源（即盖子上的蜜腺）到猪笼口前缘的距离与粪便陷阱物种中 T. montana 的头加身体长度精确匹配，这是开口大小和盖子反射角度的函数。通过对陷阱几何形状的简单修改，食虫植物的营养获取策略可能会发生重大变化。这种非凡的植物-动物相互作用增加了越来越多的证据，表明猪笼草在氮固定策略方面代表了适应性辐射的候选模型。
