| selective flower abortion maintains moth cooperation in a newly discovered pollination mutualism. | the evolutionary stability of mutualisms is enhanced when partners possess mechanisms to prevent overexploitation by one another. in obligate pollination-seed consumption mutualisms, selective abortion of flowers containing excessive eggs represents one such mechanism, but empirical tests have long been limited to the yucca-yucca moth mutualism. we present evidence for selective abortion in the recently discovered mutualism between glochidion trees and epicephala moths. in glochidion acuminatum, ... | 2010 | 20113331 |
| host-associated divergence and incipient speciation in the yucca moth prodoxus coloradensis (lepidoptera: prodoxidae) on three species of host plants. | a wide range of evolutionary processes have been implicated in the diversification of yuccas and yucca moths, which exhibit ecological relationships that extend from obligate plant-pollinator mutualisms to commensalist herbivory. prodoxus coloradensis (lepidoptera: prodoxidae) is a yucca moth, which feeds on the flowering stalks of three yucca species as larvae, but does not provide pollination service. to test for evidence of host-associated speciation, we examined the genetic structure of p. c ... | 2010 | 20010961 |
| repeated independent evolution of obligate pollination mutualism in the phyllantheae-epicephala association. | the well-known fig-fig wasp and yucca-yucca moth mutualisms are classic examples of obligate mutualisms that have been shaped by millions of years of coevolution. pollination systems involving obligate seed parasites are only expected to evolve under rare circumstances where their positive effects are not swamped by abundant co-pollinators and heavy costs resulting from seed destruction. here, we show that, in phyllantheae, specialization to pollination by epicephala moths evolved at least five ... | 2009 | 18948251 |
| pattern and timing of diversification in yucca (agavaceae): specialized pollination does not escalate rates of diversification. | the yucca-yucca moth interaction is one of the most well-known and remarkable obligate pollination mutualisms, and is an important study system for understanding coevolution. previous research suggests that specialist pollinators can promote rapid diversification in plants, and theoretical work has predicted that obligate pollination mutualism promotes cospeciation between plants and their pollinators, resulting in contemporaneous, parallel diversification. however, a lack of information about t ... | 2008 | 18048283 |
| coevolution and divergence in the joshua tree/yucca moth mutualism. | theory suggests that coevolution drives diversification in obligate pollination mutualism, but it has been difficult to disentangle the effects of coevolution from other factors. we test the hypothesis that differential selection by two sister species of pollinating yucca moths (tegeticula spp.) drove divergence between two varieties of the joshua tree (yucca brevifolia) by comparing measures of differentiation in floral and vegetative features. we show that floral features associated with polli ... | 2008 | 18462130 |
| assessment of the diversity and species specificity of the mutualistic association between epicephala moths and glochidion trees. | the obligate mutualisms between flowering plants and their seed-parasitic pollinators constitute fascinating examples of interspecific mutualisms, which are often characterized by high levels of species diversity and reciprocal species specificity. the diversification in these mutualisms has been thought to occur through simultaneous speciation of the partners, mediated by tight reciprocal adaptation; however, recent studies cast doubt over this general view. in this study, we examine the divers ... | 2006 | 17032258 |
| chemistry and geographic variation of floral scent in yucca filamentosa (agavaceae). | we identified volatiles from the floral headspace of yucca filamentosa using gas chromatography and mass spectrometry and analyzed floral scent composition and variation among populations pollinated by different yucca moth species. twenty-one scent compounds were repeatedly identified and most could be categorized into two major classes: (1) homoterpenes derived from the sesquiterpene alcohol nerolidol and (2) long chain aliphatic hydrocarbons. two biosynthetic pathways are thus responsible for ... | 2005 | 21646079 |
| mutualism favours higher host specificity than does antagonism in plant-herbivore interaction. | coevolved mutualisms often exhibit high levels of partner specificity. obligate pollination mutualisms, such as the fig-fig wasp and yucca-yucca moth systems, represent remarkable examples of such highly species-specific associations; however, the evolutionary processes underlying these patterns are poorly understood. the prevailing hypothesis suggests that the high degree of specificity in pollinating seed parasites is the fortuitous result of specialization in their ancestors because these ins ... | 2010 | 20427340 |
| the influence of interaction type and feeding location on the phylogeographic structure of the yucca moth community associated with hesperoyucca whipplei. | the interactions between herbivorous insects and their host plants have been central in generating diversification in both groups. we used a community of four yucca moth species, monophagous on the host plant hesperoyucca whipplei (agavaceae), to examine how the type of interaction and where insects feed within a plant influence phylogeographic structure of herbivorous insects. these four species included two fruit-feeders, one mutualistic and one commensalistic, and two commensalistic stalk-fee ... | 2007 | 17116409 |
| patterns of speciation in the yucca moths: parallel species radiations within the tegeticula yuccasella species complex. | the interaction between yuccas and yucca moths has been central to understanding the origin and loss of obligate mutualism and mutualism reversal. previous systematic research using mtdna sequence data and characters associated with genitalic morphology revealed that a widespread pollinator species in the genus tegeticula was in fact a complex of pollinator species that differed in host use and the placement of eggs into yucca flowers. within this mutualistic clade two nonpollinating "cheater" s ... | 2006 | 16684719 |
| limiting cheaters in mutualism: evidence from hybridization between mutualist and cheater yucca moths. | mutualisms are balanced antagonistic interactions where both species gain a net benefit. because mutualisms generate resources, they can be exploited by individuals that reap the benefits of the interaction without paying any cost. the presence of such 'cheaters' may have important consequences, yet we are only beginning to understand how cheaters evolve from mutualists and how their evolution may be curtailed within mutualistic lineages. the yucca-yucca moth pollination mutualism is an excellen ... | 2005 | 16191630 |
| patterns of genetic structure among populations of an oligophagous pollinating yucca moth (tegeticula yuccasella). | plant-insect associations have served as models for investigations of coevolution and the influence of biotic interactions on diversification. the pollination association between yuccas and yucca moths is a classic example of an obligate mutualism often suggested to have been affected by coevolution. recent work has shown high host specificity in pollinating yucca moths, and here we use tegeticula yuccasella, the species with the widest diet breadth, to ask how host specificity and isolation by ... | 2004 | 15073228 |
| cospeciation analysis of an obligate pollination mutualism: have glochidion trees (euphorbiaceae) and pollinating epicephala moths (gracillariidae) diversified in parallel? | species-specific obligate pollination mutualism between glochidion trees (euphorbiaceae) and epicephala moths (gracillariidae) involves a large number of interacting species and resembles the classically known fig-fig wasp and yucca-yucca moth associations. to assess the extent of parallel cladogenesis in glochidion-epicephala association, we reconstruct phylogenetic relationships of 18 species of glochidion using nuclear ribosomal dna sequences (internal and external transcribed spacers) and th ... | 2004 | 15562685 |
| examining genetic structure in a bogus yucca moth: a sequential approach to phylogeography. | understanding the phylogeography of a species requires not only elucidating patterns of genetic structure among populations, but also identifying the possible evolutionary events creating that structure. the use of a single phylogeographic test or analysis, however, usually provides a picture of genetic structure without revealing the possible underlying evolutionary causes. we used current analytical techniques in a sequential approach to examine genetic structure and its underlying causes in t ... | 2002 | 12353756 |
| testing the out-of-florida hypothesis on the origin of cheating in the yucca-yucca moth mutualism. | mutualistic interactions can be exploited by cheaters that take the rewards offered by mutualists without providing services in return. the evolution of cheater species from mutualist ancestors is thought to be possible under particular ecological conditions. here we provide a test of the first explicit model of the transition from mutualism to antagonism. we used the obligate pollination mutualism between yuccas and yucca moths to examine the origins of a nonpollinating cheater moth, tegeticula ... | 2004 | 15562689 |
| phylogeographic structure in the bogus yucca moth prodoxus quinquepunctellus (prodoxidae): comparisons with coexisting pollinator yucca moths. | the pollination mutualism between yucca moths and yuccas highlights the potential importance of host plant specificity in insect diversification. historically, one pollinator moth species, tegeticula yuccasella, was believed to pollinate most yuccas. recent phylogenetic studies have revealed that it is a complex of at least 13 distinct species, eight of which are specific to one yucca species. moths in the closely related genus prodoxus also specialize on yuccas, but they do not pollinate and th ... | 2001 | 11603942 |
| phylogeography of the yucca moth tegeticula maculata: the role of historical biogeography in reconciling high genetic structure with limited speciation. | tegeticula maculata is one of the most ancient and morphologically variable lineages within the yucca moths, yet has apparently undergone little diversification in comparison with much younger yucca moth lineages that have rapidly diversified. a phylogeographic approach was used to determine the number of independent lineages within t. maculata and to examine whether these patterns corresponded with morphological differences between its subspecies maculata and extranea. phylogenetic analysis of ... | 2001 | 11380881 |
| multiple occurrences of mutualism in the yucca moth lineage. | the complex mutualism between yuccas and the moths that pollinate their flowers is regarded as one of the most obvious cases of coevolution. studies of related genera show that at least two of the critical behavioral and life history traits suggested to have resulted from coevolved mutualism in yucca moths are plesiomorphic to the family. another trait, oviposition into flowers, has evolved repeatedly within the family. one species with these traits, greya politella, feeds on and pollinates plan ... | 1992 | 11607287 |
| characterizing the interaction between the bogus yucca moth and yuccas: do bogus yucca moths impact yucca reproductive success? | yucca moths are most well known for their obligate pollination mutualism with yuccas, where pollinator moths provide yuccas with pollen and, in exchange, the moth larvae feed on a subset of the developing yucca seeds. the pollinators, however, comprise only two of the three genera of yucca moths. members of the third genus, prodoxus, are the "bogus yucca moths" and are sister to the pollinator moths. adult prodoxus lack the specialized mouthparts used for pollination and the larvae feed on plant ... | 2004 | 15170561 |
| effect of pollinator-inflicted ovule damage on floral abscission in the yucca-yucca moth mutualism: the role of mechanical and chemical factors. | the long-term persistence of obligate mutualisms (over 40 mya in both fig/fig wasps and yucca/yucca moths) raises the question of how one species limits exploitation by the other species, even though there is selection pressure on individuals to maximize fitness. in the case of yuccas, moths serve as the plant's only pollinator, but eggs laid by the moths before pollination hatch into larvae that consume seeds. previous studies have shown that flowers with high egg loads are more likely to absci ... | 2003 | 12756527 |
| pollen dispersal in yucca filamentosa (agavaceae): the paradox of self-pollination behavior by tegeticula yuccasella (prodoxidae). | we investigated pollen dispersal in an obligate pollination mutualism between yucca filamentosa and tegeticula yuccasella. yucca moths are the only documented pollinator of yuccas, and moth larvae feed solely on developing yucca seeds. the quality of pollination by a female moth affects larval survival because flowers receiving small amounts of pollen or self-pollen have a high abscission probability, and larvae die in abscised flowers. we tested the prediction that yucca moths primarily perform ... | 2000 | 10811791 |
| forty million years of mutualism: evidence for eocene origin of the yucca-yucca moth association. | the obligate mutualism between yuccas and yucca moths is a major model system for the study of coevolving species interactions. exploration of the processes that have generated current diversity and associations within this mutualism requires robust phylogenies and timelines for both moths and yuccas. here we establish a molecular clock for the moths based on mtdna and use it to estimate the time of major life history events within the yucca moths. colonization of yuccas had occurred by 41.5 +/- ... | 1999 | 10430916 |
| how to become a yucca moth: minimal trait evolution needed to establish the obligate pollination mutualism. | the origins of obligate pollination mutualisms, such as the classic yucca-yucca moth association, appear to require extensive trait evolution and specialization. to understand the extent to which traits truly evolved as part of establishing the mutualistic relationship, rather than being preadaptations, we used an expanded phylogenetic estimate with improved sampling of deeply-diverged groups to perform the first formal reconstruction of trait evolution in pollinating yucca moths and their non-p ... | 2010 | 20730026 |
| economic contract theory tests models of mutualism. | although mutualisms are common in all ecological communities and have played key roles in the diversification of life, our current understanding of the evolution of cooperation applies mostly to social behavior within a species. a central question is whether mutualisms persist because hosts have evolved costly punishment of cheaters. here, we use the economic theory of employment contracts to formulate and distinguish between two mechanisms that have been proposed to prevent cheating in host-sym ... | 2010 | 20733067 |
| non-mutualistic yucca moths and their evolutionary consequences. | interspecific mutualisms are regarded as having evolved from antagonistic or commensalistic interactions, with most mutualisms remaining facultative but some having coevolved into obligate reciprocal dependency. underlying mutualism is an intrinsic conflict between the parties, in that each is under selection for increased exploitation of the other. theoretical models suggest that this conflict is a source of evolutionary instability, and that evolution of 'cheating' by one party may lead to rec ... | 1996 | 8600388 |
| distinguishing mechanisms for the evolution of co-operation. | the existence of co-operation between species has been cast as a problem to the selfish-gene view of evolution: why does co-operation persist, when it would seem that individual selection should favor the unco-operative individual who exploits the co-operative tendencies of its partner and gives nothing in return? the recent literature has emphasized one type of model as underlying the evolution and stability of interspecific co-operation, which we term the "partner-fidelity" model, and which is ... | 1991 | 1881147 |
| genetic diversity and population structure of yucca filamentosa (agavaceae). | using 19 allozyme loci we studied genetic diversity in 18 populations of yucca filamentosa (agavaceae) from the southeastern united states. of the 19 loci surveyed, 17 (89.5%) were polymorphic in at least one of the populations sampled. there was considerable variation among populations in the percentage of polymorphic loci (range = 31.6-84.2%, mean = 67.6%). similar heterogeneity among populations was observed for mean number of alleles per polymorphic locus (range = 2.0-3.0; mean = 2.48) and m ... | 1998 | 21684917 |
| evolution of obligate pollination mutualism in new caledonian phyllanthus (euphorbiaceae). | about half a dozen obligate pollination mutualisms between plants and their seed-consuming pollinators are currently recognized, including fig-fig wasp, yucca-yucca moth, and the recently discovered glochidion tree-epicephala moth mutualisms. a common principle among these interactions is that the pollinators consume only a limited amount of the seed crop within a developing fruit (or fig in the case of fig-fig wasp mutualism), thereby ensuring a net benefit to plant reproduction. a novel obliga ... | 2004 | 21653396 |
| Comparative phylogeography of a coevolved community: concerted population expansions in Joshua trees and four yucca moths. | Comparative phylogeographic studies have had mixed success in identifying common phylogeographic patterns among co-distributed organisms. Whereas some have found broadly similar patterns across a diverse array of taxa, others have found that the histories of different species are more idiosyncratic than congruent. The variation in the results of comparative phylogeographic studies could indicate that the extent to which sympatrically-distributed organisms share common biogeographic histories var ... | 2011 | 22028785 |
| multiple origins of the yucca-yucca moth association. | the association of species of yucca and their pollinating moths is considered one of the two classic cases of obligate mutualism between floral hosts and their pollinators. the system involves the active collection of pollen by females of two prodoxid moth genera and the subsequent purposeful placement of the pollen on conspecific stigmas of species of yucca. yuccas essentially depend on the moths for pollination and the moths require yucca ovaries for oviposition. because of the specificity inv ... | 1995 | 7624333 |
| the extension of the yucca moth. | | 1925 | 17800234 |
| benefit and cost curves for typical pollination mutualisms. | mutualisms provide benefits to interacting species, but they also involve costs. if costs come to exceed benefits as population density or the frequency of encounters between species increases, the interaction will no longer be mutualistic. thus curves that represent benefits and costs as functions of interaction frequency are important tools for predicting when a mutualism will tip over into antagonism. currently, most of what we know about benefit and cost curves in pollination mutualisms come ... | 2010 | 20503861 |
| geographic isolation trumps coevolution as a driver of yucca and yucca moth diversification. | coevolution is thought to be especially important in diversification of obligate mutualistic interactions such as the one between yuccas and pollinating yucca moths. we took a three-step approach to examine if plant and pollinator speciation events were likely driven by coevolution. first, we tested whether there has been co-speciation between yuccas and pollinator yucca moths in the genus tegeticula (prodoxidae). second, we tested whether co-speciation also occurred between yuccas and commensal ... | 2011 | 22178365 |
| economic game theory for mutualism and cooperation. | we review recent work at the interface of economic game theory and evolutionary biology that provides new insights into the evolution of partner choice, host sanctions, partner fidelity feedback and public goods. (1) the theory of games with asymmetrical information shows that the right incentives allow hosts to screen-out parasites and screen-in mutualists, explaining successful partner choice in the absence of signalling. applications range from ant-plants to microbiomes. (2) contract theory d ... | 2011 | 22011186 |