Rolf Hoekstra in News and Views (“Why sex is good” Nature 434, 571; 2005) surely overstates the contribution of sexual reproduction to the aesthetic appeal of nature. He assumes that complex organisms similar to flowering plants, insects and peacocks would evolve, but that without sex the world would be drab and colourless. However, asexually reproducing plants would probably still take advantage of animals for spore dispersal, producing fruits or other rewards (advertised by special structures) as ‘payment’. Indeed it is likely that our colour vision developed in order to detect ripe fruits, which have little to do with sex and a lot to do with seed dispersal.
Similarly, although it is true that many gaudy avian displays are aimed at mate attraction, there are many brightly coloured animals whose decoration serves as a threat or warning. Colonial bees, wasps and many butterflies and moths all bear distinctive and colourful markings discouraging interference.
Sexual reproduction, in maintaining genetic heterogeneity within a population, is clearly a major mechanism by which species survive catastrophes and adapt to the subsequent conditions. However, the pro-sex lobby always seems to downplay the importance of asexual reproduction to evolution in stable environments. Apomictic organisms (not strictly asexual of course), such as dandelions, can develop localized populations accumulating mutations that render them distinct from other members of their clade. This kind of diversification is rarely seen in sexually reproducing populations unless they are subjected to selective pressure.
Sex is good, but it ain't everything.