 A classic symbiotic relationship is found in lichens, which are made of tightly integrated fungi and photosynthesizing microbes (algae, cyanobacteria or both). Although the contributing organisms reproduce separately, they form similarly organized units of lichen, generation after generation. Benefits are often thought to accrue for both partners, and are cashed out as higher reproductive fitness (Honegger 1998; however, cf. Hyvärinen et al. 2002). Many other symbioses are intimate and persistent, but more obviously manipulate at least one of the partners in the arrangement. A curious example is the bacterium Wolbachia in insects. This bacterium is obligately part of the insect reproductive process. It can “feminize” insect embryos and kill males to ensure its own reproduction (Werren et al. 2008). But despite Wolbachia hijacking the insect for its own reproductive requirements, there are variable fitness benefits for its host (e.g., Fry et al. 2004). In some host-symbiont systems, Wolbachia and the insect can benefit, despite the manipulation of the latter by the former.