Matching Items (3)
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Description
Persistent cooperation between unrelated conspecifics rarely occurs in mature eusocial insect societies. In this dissertation, I present evidence of non-kin cooperation in the Nearctic honey ant Myrmecocystus mendax. Using microsatellite markers, I show that mature colonies in the Sierra Ancha Mountain of central Arizona contain multiple unrelated matrilines, an observation

Persistent cooperation between unrelated conspecifics rarely occurs in mature eusocial insect societies. In this dissertation, I present evidence of non-kin cooperation in the Nearctic honey ant Myrmecocystus mendax. Using microsatellite markers, I show that mature colonies in the Sierra Ancha Mountain of central Arizona contain multiple unrelated matrilines, an observation that is consistent with primary polygyny. In contrast, similar analyses suggest that colonies in the Chiricahua Mountains of southeastern Arizona are primarily monogynous. These interpretations are consistent with field and laboratory observations. Whereas cooperative colony founding was observed frequently among groups of Sierra Ancha foundresses, founding in the Chiricahua population was restricted to individual foundresses. Furthermore, Sierra Ancha foundresses successfully established incipient laboratory colonies without undergoing queen culling following emergence of the first workers. Multi-queen laboratory Sierra Ancha colonies also produced more workers and repletes than haplometrotic colonies, and when brood raiding was induced between colonies, queens of those with more workers had a higher survival probability.

Microsatellite analyses of additional locations within the M. mendax range suggest that polygyny is also present in some other populations, especially in central-northern Arizona, albeit at lower frequencies than that in the Sierra Anchas. In addition, analyses of multiple types of genetic data, including microsatellites, the mitochondrial barcoding region, and over 2000 nuclear ultra-conserved elements indicate that M. mendax populations within the southwestern U.S. and northwestern Mexico are geographically structured, with strong support for the existence of two or more divergent clades as well as isolation-by-distance within clades. This structure is further shown to correlate with variation in queen number and hair length, a diagnostic taxonomic feature used to distinguish honey ant species.

Together, these findings suggest that regional ecological pressures (e.g. colony density , climate) may have acted on colony founding and social strategy to select for increasing workforce size and, along with genetic drift, have driven geographically isolated M. mendax populations to differentiate genetically and morphologically. The presence of colony fusion in the laboratory and life history traits in honey ant that are influenced by colony size, including repletism, brood raiding, and tournament, support this evolutionary scenario.
ContributorsEriksson, Ti (Author) / Gadau, Jürgen (Thesis advisor) / Taylor, Jay (Thesis advisor) / Fewell, Jennifer (Committee member) / Hӧlldobler, Bert (Committee member) / Johnson, Robert (Committee member) / Pratt, Stephen (Committee member) / Arizona State University (Publisher)
Created2018
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Description

Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with

Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with similar data for eusocial Hymenoptera, to better identify commonalities and differences in achieving this significant transition. We show an expansion of genes related to male fertility, with upregulated gene expression in male reproductive individuals reflecting the profound differences in mating biology relative to the Hymenoptera. For several chemoreceptor families, we show divergent numbers of genes, which may correspond to the more claustral lifestyle of these termites. We also show similarities in the number and expression of genes related to caste determination mechanisms. Finally, patterns of DNA methylation and alternative splicing support a hypothesized epigenetic regulation of caste differentiation.

ContributorsTerrapon, Nicolas (Author) / Li, Cai (Author) / Robertson, Hugh M. (Author) / Ji, Lu (Author) / Meng, Xuehong (Author) / Booth, Warren (Author) / Chen, Zhensheng (Author) / Childers, Christopher P. (Author) / Glastad, Karl M. (Author) / Gokhale, Kaustubh (Author) / Gowin, Johannes (Author) / Gronenberg, Wulfila (Author) / Hermansen, Russell A. (Author) / Hu, Haofu (Author) / Hunt, Brendan G. (Author) / Huylmans, Ann Kathrin (Author) / Khalil, Sayed M. S. (Author) / Mitchell, Robert D. (Author) / Munoz-Torres, Monica C. (Author) / Mustard, Julie (Author) / Pan, Hailin (Author) / Reese, Justin T. (Author) / Scharf, Michael E. (Author) / Sun, Fengming (Author) / Vogel, Heiko (Author) / Xiao, Jin (Author) / Yang, Wei (Author) / Yang, Zhikai (Author) / Yang, Zuoquan (Author) / Zhou, Jiajian (Author) / Zhu, Jiwei (Author) / Brent, Colin S. (Author) / Elsik, Christine G. (Author) / Goodisman, Michael A. D. (Author) / Liberles, David A. (Author) / Roe, R. Michael (Author) / Vargo, Edward L. (Author) / Vilcinskas, Andreas (Author) / Wang, Jun (Author) / Bornberg-Bauer, Erich (Author) / Korb, Judith (Author) / Zhang, Guojie (Author) / Liebig, Juergen (Author) / College of Liberal Arts and Sciences (Contributor)
Created2014-05-20
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Description

A central goal of biology is to uncover the genetic basis for the origin of new phenotypes. A particularly effective approach is to examine the genomic architecture of species that have secondarily lost a phenotype with respect to their close relatives. In the eusocial Hymenoptera, queens and workers have divergent

A central goal of biology is to uncover the genetic basis for the origin of new phenotypes. A particularly effective approach is to examine the genomic architecture of species that have secondarily lost a phenotype with respect to their close relatives. In the eusocial Hymenoptera, queens and workers have divergent phenotypes that may be produced via either expression of alternative sets of caste-specific genes and pathways or differences in expression patterns of a shared set of multifunctional genes. To distinguish between these two hypotheses, we investigated how secondary loss of the worker phenotype in workerless ant social parasites impacted genome evolution across two independent origins of social parasitism in the ant genera Pogonomyrmex and Vollenhovia. We sequenced the genomes of three social parasites and their most-closely related eusocial host species and compared gene losses in social parasites with gene expression differences between host queens and workers. Virtually all annotated genes were expressed to some degree in both castes of the host, with most shifting in queen-worker bias across developmental stages. As a result, despite >1 My of divergence from the last common ancestor that had workers, the social parasites showed strikingly little evidence of gene loss, damaging mutations, or shifts in selection regime resulting from loss of the worker caste. This suggests that regulatory changes within a multifunctional genome, rather than sequence differences, have played a predominant role in the evolution of social parasitism, and perhaps also in the many gains and losses of phenotypes in the social insects.

ContributorsSmith, Chris R. (Author) / Helms Cahan, Sara (Author) / Kemena, Carsten (Author) / Brady, Sean G. (Author) / Yang, Wei (Author) / Bornberg-Bauer, Erich (Author) / Eriksson, Ti (Author) / Gadau, Juergen (Author) / Helmkampf, Martin (Author) / Gotzek, Dietrich (Author) / Okamoto Miyakawa, Misato (Author) / Suarez, Andrew V. (Author) / Mikheyev, Alexander (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-07-29