Ehleringer J R, Ullmann I, Lange O L, Farquhar G D, Cowan I R, Schulze E-D, Ziegler H
Department of Biology, University of Utah, 84112, Salt Lake City, UT, USA.
Lehrstuhl für Botanik II der Universität, Mittlerer Dallenbergweg 64, D-8700, Würzburg, Federal Republic of Germany.
Oecologia. 1986 Sep;70(2):234-237. doi: 10.1007/BF00379245.
Leaves from many misletoe species in Australia strongly resemble those of their hosts. This cryptic mimicry has been hypothesized to be a means of reducing the likelihood of mistletoe herbivory by vertebrates. Leaf Kjeldahl nitrogen contents (a measure of reduced nitrogen and thus amines, amino acids and protein levels) of mistletoes and their hosts were measured on 48 mimetic and nonmimetic host-parasite pairs to evaluate hypotheses concerning the significance of crysis versus noncrypsis. The hypothesis that mistletoes mimicking host leaves should have higher leaf nitrogen levels than their hosts is supported; they may be gaining a selective advantage through crypsis (reduced herbivory). The second hypothesis that mistletoes which do not mimic their hosts should have lower leaf nitrogen levels than their hosts is also supported; they may be gaining a selective advantage through noncrypsis (reduced herbivory resulting from visual advertisement of their reduced nutritional status).
澳大利亚许多槲寄生物种的叶子与它们的寄主植物的叶子极为相似。这种隐秘拟态被认为是一种降低脊椎动物取食槲寄生可能性的手段。对48对具有拟态和非拟态关系的寄主 - 寄生植物组合，测量了槲寄生及其寄主的叶片凯氏氮含量（一种衡量还原态氮，进而反映胺、氨基酸和蛋白质水平的指标），以评估有关拟态与非拟态意义的假说。槲寄生模仿寄主叶片应比寄主具有更高叶片氮含量这一假说得到了支持；它们可能通过拟态（减少被取食）获得了选择优势。槲寄生不模仿寄主时应比寄主具有更低叶片氮含量这第二个假说也得到了支持；它们可能通过非拟态（因营养状况降低的视觉展示而减少被取食）获得了选择优势。
