Parasitoids play a fundamental role in the regulation of herbivore pests in natural settings. Flower resources can be used to provide natural enemies with suitable food sources that are otherwise lacking in modern agro-ecosystems, in order to enhance biological pest control. However, the introduction of flower resources can also enhance the fitness of the pests. This thesis investigated the potential of floral resources in enhancing the biological control of the cabbage moth Mamestra brassicae (L.) (Lepidoptera: Noctuidae) by its main parasitoid Microplitis mediator (Haliday) (Hymenoptera: Braconidae). A thorough review of available data showed that most parasitoids strongly depend on adult feeding for survival and that some flower species are selective, i.e. they only enhance the fitness of the parasitoids and not the pests. I performed laboratory experiments to identify selective flower species that enhance the fitness of M mediator, without benefiting its host, M brassicae. Longevity and parasitization rates by M mediator increased significantly with Centaurea cyanus, Fagopyrum esculentum and Vicia sativa. Longevity and fecundity of the pest were not affected by the plant species tested. I further studied the ability of M mediator to locate extrafloral nectar of C. cyanus. Female M mediator showed an innate attraction to olfactory cues of floral but not extrafloral nectar of C. cyanus. The most promising plant identified, C. cyanus, was assessed with regard to its effect on parasitization rates of M brassicae and crop yield in a two-year large-scale replicated field experiment. Parasitization rates of M brassicae significantly increased in the treatment with C. cyanus, resulting in a significant increase in the marketable cabbage weight in this treatment in 2009. These results emphasize the importance of plant screening in identifying selective plant species and underline the potential of flowering companion plants as new habitats, resulting in an increase in the success of biological control programs.

Paenibacillus larvae is the causative agent of American foulbrood (AFB), a damaging disease of honey bees (Apis mellifera) with a global distribution. AFB infects the honey bee larvae through spore-contaminated larval food and once infected the larvae will die within twelve days. AFB infection leads to the eventual death of the honey bee colony. In many countries the best control method is thought to be the destruction of the colony, to destroy the hardy, infectious spores. Therefore infection nearly always leads to the death of the colony. In the UK cases of the disease have decreased in recent years due to statutory control methods, however sporadic outbreaks occur each year. Many advances have been made in our knowledge of the mechanisms of infection by P. larvae in recent years however, a high resolution, standardised method of strain typing is required to track disease spread and understand outbreak sources. This thesis describes the development of the first multilocus sequence typing (MLST) scheme for P. larvae. MLST is the gold standard for pathogenic bacteria typing. It is based on the sequencing of sections of 6-10 housekeeping genes. MLST is standardised, as primer and allele sequences can be made available for other researchers. The new MLST scheme was used to describe previously undetectable patterns of distribution at a global level as well as at a national level. Humans and bees are implicated in the movement of the disease over different spatial scales. Using the MLST scheme a diverse group of isolates were selected for whole genome sequencing. For the first time multiple genomes were compared within and between genotypes. The ability of the MLST scheme to describe relationships amongst sequence types (STs) was tested by comparing phylogenies based on core genes and MLST sequences. I describe the discovery of seven plasmids in four STs previously unknown to harbour plasmids.

The detection and control of American Foulbrood (AFB) is made more challenging due to a lack of evidence regarding the virulence mechanisms employed by this honeybee pathogen. Whilst incidence of this pathogen within the UK has recently declined, ~100 colonies were identified as infected with AFB in 2011 (to end of September), so AFB should still be considered a serious threat to honeybee health. It is known that within the species many phenotypes exist, and the infection caused by the phenotypes differs greatly. This PhD thesis presents several advances towards a greater understanding of the intra-specific differences occurring within the species. Chapter 2 evaluates the use of 16S rRNA sequencing as a method of Paenibacillus larvae identification, as well as exploring the use of this ribosomal subunit for differentiation of the species. The sequencing of two housekeeping (purH and PyrE) genes assesses the potential of a Multi Locus Sequence Typing (MLST) method, as a means of subspecies differentiation. Chapter 3 assesses what can be inferred from use of Enterobacterial Repetitive Intergenic Consensus (ERIC) sequence fingerprinting, with regards to prior knowledge genetic differences. Lateral Flow Devices (LFDs), a commonly used diagnostic tool, are tested to ensure P. larvae isolates representing all 4 ERIC types are detected. In Chapter 4 an in-vitro honeybee rearing method is employed to observe the correlation between proteolytic activity of isolates and in-vitro virulence. The method is applied to a wider range of reference isolates, to observe the intra-species differences existing. The ability to produce large numbers of viable spores is explored as a potential difference existing between ERIC types I and IV. Whole genome shotgun sequencing is used in chapter 5 to perform comparative genomic studies on 4 P. larvae isolates also utilising 646 contigs from a previous sequencing project. The possible presence of plasmid DNA is explored, through GC content analysis. The genetic basis of a sporulation phenotypic difference is examined by BLAST analysis of orthologous genes. In Chapter 6 the findings of this thesis are discussed in more detail, and potential areas of further study are identified.

[許兆理]. / 手稿複寫本. / 論文(碩士) -- 香港中文大學. / Shou gao fu xie ben. / [Xu Zhaoli]. / Lun wen (shuo shi) -- xiang gang zhong wen da xue. / Chapter 第一章 --- 序論 --- p.1 / Chapter 第二章 --- 惠能的歷史淵源 --- p.23 / Chapter 一 --- 達摩及其二入四行的學說 --- p.24 / Chapter 二 --- 慧可和僧粲以及楞伽宗之得名 --- p.28 / Chapter 三 --- 道信的師承及其開始重般若 --- p.32 / Chapter 四 --- 弘忍和神秀惠能的關係及本章的結論 --- p.34 / Chapter 第三章 --- 從即度禪法和天臺止觀說到惠能的定慧不于義 --- p.37 / Chapter 一 --- 印度禪法的種類及其安點 --- p.38 / Chapter 二 --- 天台止觀的特色 --- p.47 / Chapter 三 --- 惠能的定慧不二義 --- p.54 / Chapter 第四章 --- 從般若宗的思想說到惠能的般若義 --- p.59 / Chapter 一 --- 般若宗思想通論 --- p.60 / Chapter 二 --- 六家七宗的般若學的偏差 --- p.63 / Chapter 三 --- 僧肇般若學的特色 --- p.68 / Chapter 四 --- 惠能和般若宗的關係 --- p.72 / Chapter 五 --- 由相非到相即 --- p.74 / Chapter 六 --- 惠能對般若自性的體會 --- p.76 / Chapter 七 --- 實踐般若自性的重要 --- p.80 / Chapter 第五章 --- 從大般涅槃經、竺道生和諸家的佛性論說到惠能的自性義 --- p.82 / Chapter 一 --- 大般涅槃經的主要思想 --- p.83 / Chapter 二 --- 竺道生在佛性論方面的成就 --- p.93 / Chapter 三 --- 竺道生以後諸家的佛性論 --- p.96 / Chapter 四 --- 從佛性到自性以及「自性」詞之意義的轉變 --- p.99 / Chapter 五 --- 從惠能悟道的語言以論他對「自性」的體會 --- p.102 / Chapter 六 --- 乘歸一、自性三身佛和自性淨土 --- p.106 / Chapter 第六章 --- 從佛教的漸修及竺道生的頓悟說到惠能的頓悟義 --- p.110 / Chapter 一 --- 佛教的漸修方法 --- p.111 / Chapter 二 --- 竺道生的頓悟說 --- p.114 / Chapter 三 --- 惠能對頓教的重視 --- p.118 / Chapter 四 --- 頓悟就是般若自性的呈現 --- p.120 / Chapter 五 --- 頓悟是（自覺）逆覺的工夫 --- p.122 / Chapter 六 --- 頓悟不假文字 --- p.124 / Chapter 七 --- 頓悟即自悟 --- p.126 / Chapter 八 --- 頓悟與漸修的分別 --- p.129 / Chapter 第七章 --- 惠能以後禪宗的發展和惠能的關係 --- p.134 / Chapter 一 --- 神會和惠能 --- p.135 / Chapter 二 --- 即心即佛 --- p.140 / Chapter 三 --- 佛法不離日常生活 --- p.142 / Chapter 四 --- 文學語言的運用 --- p.144 / Chapter 五 --- 棒喝的宗風 --- p.147 / Chapter 六 --- 無意義的對答語句 --- p.150 / Chapter 第八章 --- 惠能與儒家言心性義的比較 --- p.154 / Chapter 一 --- 何以要比較惠能和儒家之心性義 --- p.155 / Chapter 二 --- 心即是性 --- p.157 / Chapter 三 --- 成聖成佛的先天根據 --- p.159 / Chapter 四 --- 意志之絶對自由 --- p.160 / Chapter 五 --- 般若心興仁心的分別 --- p.161 / Chapter 六 --- 惠能思想的限度 --- p.163

The PhD work aligns technological opportunities with self-selecting motivated participants, investigating their desire to monitor wildlife within their custody. It used an ethnographic and user- centred design approach with amateur beekeepers. The work built reciprocal interest in data which users could gather from self-assembled monitoring tools. This PhD explores the relationship between Open Design and Citizen Science, testing it ‘in-the-wild’ through the Bee Lab kit. The development of the kit and territory research was carried out in close collaboration with a local beekeeping community based in the South East of England. The work engaged with the British Beekeepers Association (BBKA), a Citizen Science stakeholder and technology provider Technology Will Save Us (TWSU), informing the project at each stage. The PhD territory was highlighted in scoping design workshops with the public (Phillips. R, Baurley. S, Silve. S) and developed into: cultural probes deployed nationally investigating beekeepers’ ‘making’ activities (Phillips. R, Baurley. S, Silve. S 2013b), ethnographic studies identifying beekeepers’ product creations and re-appropriations for beekeeping praxis, participatory design workshops establishing lay users’ ‘technologically enabled conversations with bees’ (Phillips. R, Ford. Y, Sadler. K, Silve. S, Baurley. S 2013), technology kit assembly workshops testing kit design and competence of lay users (Phillips, Blum et al. 2014), and mental models of creating instructional content (Phillips, Robert., Lockton, Dan., Baurley, Sharon & Silve, Sarah 2013). The Bee Lab Kit: activities engaging motivated lay users in the use of open technologies for CS activities Page 2 of 265 The creation of a repeatable Open Design/Citizen Science model based upon the live testing from the Bee Lab project appendix (O) Open Design Standards (paper pending publication) appendix (K) The project worked with Citizen Science Vendors, Sussex Wildlife Trust and Cornell Laboratory of Ornithology, ascertaining the framing of Open Design/Citizen Science projects through a design toolkit. The design toolkit invention and testing was carried out with conservation organisations (Phillips, R & Baurley, S 2014) and technology kit deployment ‘in-the-wild’ with end users (Phillips, R., Blum, J., Brown, M. & Baurley, S 2014). Finally, the work identified the motivations of the individual stakeholders within the project.

Bees provide important and economically valuable pollination services to agriculture and other ecosystems. Recent global honeybee declines have been attributed to pesticides, which can ultimately affect the overall functioning and survival of a colony. Various routes of exposure include contaminated beeswax, pollen and nectar. This thesis presents work which examines the presence, accumulation and levels of pesticides found within a number of honeybee related matrices and bumblebee bodies, with four main aims to this study. Firstly, determine which pesticides are contained within beeswax from around the UK. Secondly, monitor which pesticides accumulate in beeswax over a two year period. Thirdly, measure residual neonicotinoid levels in oilseed rape (OSR) nectar and pollen samples. Finally, quantify the levels of thiamethoxam and metabolite clothianidin in bumblebees, following feeding trial exposure, as part of a collaborative study. Analysis was conducted using gas chromatography–mass spectrometry (GC-MS) and quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LC/MS), utilising the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method. Bumblebee samples were extracted using a refined in-house procedure. Results evidenced apiculturally applied chemical treatments to be most likely found in beeswax samples whilst tau-Fluvalinate was most persistent and likely to accumulate in the hive, including foundation wax not exposed to such treatment. Varied levels of neonicotinoids were identified in hand-collected OSR nectar samples; and there require a greater level of analysis, to further understand the implications of these results on UK bees. No quantifiable levels were detected in pollen. Bumblebee analysis determined possible levels of exposure to thiamethoxam during feeding. This thesis provides the first known attempt of identifying pesticide presence and accumulation within UK beeswax, in addition to the levels within UK OSR nectar and pollen. The findings may have wider implications on the beekeeping community. Also presented are various methodologies suitable for future research.

Urban densification and a rise in human population call for greater investigation into how the urban-rural gradient can influence bees and their pollination services. This thesis aimed to further current knowledge by: (i) sampling bee assemblages along the urban-rural gradient in Birmingham, UK; (ii) increasing documentation of bee traits associated with pollen carryover; (iii) incorporating a trait-based analysis to bee assemblage change along the urban-rural gradient; (iv) testing whether the pollination services along the same gradient varied between land-use types and (v) investigating the provisioning and reproductive success of bees in the urban environment. This thesis supports previous evidence of species-specific variation by urbanisation and shows how trait composition and trait diversity are influenced by bee assemblage change along the urban-rural gradient. However, this recorded assemblage and trait variation appeared not to alter seed-set in Campanula glomerata between urban and rural areas. I also found that nutritional quality could play an important role in provisioning rate in the solitary bee \(Osmia\) \(bicornis\), with greater offspring produced in sites where more protein was found in provisioned pollen in urban areas. Furthermore, the inter-specific variation in pilosity (which could have an important role to play in pollen carryover and subsequent pollination) can be explained by body size and species’ pollen transport adaptation. From this work, I suggest trait based analysis could be a common framework for future studies to measure bee assemblage change between urban and rural areas. Moreover, this research builds on previous work which suggests that particular traits affect pollen transport and subsequent pollination, and that further detailed study could give clues as to how changing bee assemblages could influence pollination.

The honey bee, Apis mellifera, is important both ecologically and economically. Pests and diseases are arguably the greatest current challenge faced by honey bees and beekeeping. This PhD thesis is focused on honey bee disease control including natural resistance by means of hygienic behaviour. It contains eleven independent experiments, ten on honey bee pests and diseases and their control and resistance, and one on stingless bees. Each is written as a separate chapter, Chapters 4 and 14 of this thesis. Chapter 4: How effective is Apistan® at killing varroa? This shows that Apistan is not very effective at killing varroa, presumably because of resistance. It also shows that a single Apistan treatment resulted in the next treatment being significantly less effective, indicating strong selection for resistance. Chapter 5: Towards integrated control of varroa: comparing application methods and doses of oxalic acid on the mortality of phoretic Varroa destructor mites and their honey bee hosts. This shows that oxalic acid can be highly effective at killing varroa mites under beekeeping conditions in broodless hives in winter. However, varroa mortality is affected by application method and dose. In addition, bee and colony mortality and colony performance are also affected by application method and dose. The results of this chapter shows that sublimation is the best method, in that it gives greater varroa mortality at lower doses, and results in no harm to the colonies. In fact, colonies treated via sublimation had significantly more brood in spring that controls, and lower winter mortality, although this difference was not significant. Chapter 6: Towards integrated control of varroa: varroa mortality from treating broodless winter colonies twice with oxalic acid via sublimation. This shows that two treatments of 2.25 g oxalic acid via sublimation at an interval of 2 weeks in broodless honey bee colonies in winter result in greater varroa mortality than a single treatment, 99.6% vs. 97%. Making a second oxalic acid treatment was not harmful as the performance (frames of brood, queen and colony survival) of the twice-treated colonies over the next 4 months was not significantly different to the once-treated control colonies. Chapter 7: Towards integrated control of varroa: Efficacy of early spring trapping in drone brood. This indicates that trapping in drone brood in spring is probably not sufficiently effective to be able to control varroa populations on its own. It shows that trapping varroa in capped drone cells in early spring is not highly effective at controlling varroa. The first and second test frames of drone foundation removed 44% and 48% of the varroa, respectively. Chapter 8: Towards integrated control of varroa: Monitoring honey bee brood rearing in winter and the proportion of varroa in small patches of sealed cells. This shows that December is the month with the least brood. However, winter reduction in brood rearing varied among years and even in December some colonies still had sealed brood. Although the amounts of sealed brood were low, even a small patch of c. 500-600 sealed cells could contain 14% of the varroa in a colony. This will halve the duration of control provided by an oxalic acid treatment. Chapter 9: Towards integrated control of varroa: effect of variation in hygienic behaviour among honey bee colonies on mite population increase and deformed wing virus incidence. This shows clearly that hygienic behaviour reduces the one-year population growth of varroa in honey bee colonies by more than 50% and reduces the levels of deformed wing virus by more than 1000 times. Chapter 10: Hygienic behaviour saves the lives of honey bee colonies. This shows that hygienic behaviour saves the lives of honey bee colonies with shrivelled wings, a visible symptom of deformed wing virus that is considered a predictor of colony death. Over one year, only 2 of 11 colonies requeened with a non-hygienic queen survived, versus 13 of 15 requeened with a hygienic queen. Chapter 11: Hygienic behaviour by non-hygienic honey bee colonies: all colonies remove dead brood from open cells. This shows that all honey bee colonies are highly hygienic in response to dead or diseased brood in open cells. All larvae killed by freezing with liquid nitrogen and larvae with chalkbrood disease were removed. This was true even for colonies with low levels of removal of dead brood from sealed cells, which would be considered as non-hygienic colonies. Chapter 12: Removal of larvae infected by different strains of chalk brood and other fungi by hygienic and non-hygienic bee colonies. This shows that hygienic and non-hygienic honey bee colonies are highly hygienic in response to diseased larvae killed with different strains of fungus in open cells. Chapter 13: Hygienic behaviour in Brazilian stingless bees. This shows that the three stingless bee species studied (Melipona scutellaris, Scaptotrigona depilis, Tetragonisca angustula) all have high levels of hygienic behaviour, quantified as the removal of freeze-killed brood, in comparison to the honey bee Apis mellifera. In S. depilis there was considerable variation in hygienic behaviour among colonies, and hygienic colonies removed more brood affected by a naturally-occurring disease which we discovered and for which the causative agent remains to be identified. Chapter 14: First record of small hive beetle, Aethina tumida Murray, in South America. This reports the discovery of adult small hive beetles, Aethina tumida, in honey bee, Apis mellifera, hives in an apiary in Brazil, in March 2015. This is the first record for South America of this honey bee pest.

Las abejas sin aguijón (tribu Meliponini) son un grupo de insectos sociales de la subfamilia Apinae formado por 42 géneros y un elevado número de especies, alrededor de 500, en las áreas tropicales. Dentro de su distribución, el área Neotropical es la que alberga una mayor diversidad y número de especies. Estos insectos tienen un papel muy importante como polinizadores generalistas tanto de la flora silvestre como en cultivos de gran importancia económica. Según numerosos estudios hay evidencias que apuntan a un declive mundial de las abejas y esto se acentúa más en las abejas sin aguijón por su particular biología y su distribución en zonas más amenazadas. En esta tesis nos hemos centrado en las tres especies del género Scaptotrigona que se encuentran distribuidas en México y el norte de Guatemala. Este género tiene una elevada diversidad de especies con 22 especies descritas y evidencias de especies crípticas. Para tratar de esclarecer el estado taxonómico de las especies S. mexicana, S. pectoralis y S. hellwegeri hemos utilizado marcadores morfométricos y moleculares para definir los taxones proclives a ser conservados. Se tomaron muestras de un total de 121 colonias (19 S. hellwegeri, 67 S. mexicana y 35 S. pectoralis) a través de su distribución, tanto de colonias salvajes como manejadas. Se utilizaron de una a seis obreras por colonia para detectar la variación de la forma del ala, mientras que un obrera por colonia se genotipo con siete loci de microsatélites polimórficos. En el primer capítulo, la técnica del código de barras genético (DNA barcoding) se ha utilizado con éxito para caracterizar e identificar la biodiversidad de manera rápida y fiable. Este método sugirió la existencia de especies crípticas dentro de S. mexicana y corroboró relaciones filogenéticas corroboradas previamente entre las tres especies. En el segundo capítulo, basándonos en evidencias previas de la alta diversidad subyacente en las especies de Scaptotrigona, analizamos dos especies, S. mexicana y S. pectoralis, tanto con la morfometría geométrica como con microsatélites para comprobar la existencia de, al menos, dos especies en S. mexicana, y para investigar el estado de la especie S. pectoralis. Ambas técnicas mostraron diferencias entre las poblaciones de S. mexicana de la costa del Pacífico (Sm1) y las del Atlántico (Sm2) pero no se observó diferenciación en las poblaciones de S. pectoralis. Estos resultados revelaron una diferenciación de dos unidades evolutivas en S. mexicana, lo que sugiere la necesidad de una revisión taxonómica y el desarrollo de actividades de manejo y conservación para preservar dicha diversidad. En el último capítulo se testó la delimitación de especies mediante marcadores moleculares a través de la realización de análisis (árboles filogenéticos y límites de especies dentro de un enfoque de coalescencia bayesiano) para confirmar el soporte de las especies putativas. Primero, se obtuvieron dos hipótesis diferentes con cuatro y seis especies. Posteriormente, la validación de dichas hipótesis de especies mediante un análisis objetivo que reduce el sesgo introducido por el investigador, respaldó un escenario con cuatro especies donde se confirma que S. mexicana es un complejo de dos especies (Sm1 y Sm2) distribuidas a lo largo de las costas del Pacífico y del Atlántico respectivamente. Por ello, se recomienda el manejo de ambas especies de manera separada evitando el intercambio de colonias para conservar ambos taxones. Por otro lado, S. pectoralis y S. hellwegeri se confirmaron como especies únicas pero con signos de diferenciación entre sus poblaciones. Esta tesis ha explorado el patrón de diferenciación dentro de las especies S. hellwegeri, S. mexicana y S. pectoralis distribuidas en México y en el norte de Guatemala. Nuestros resultados de la morfología geométrica y de los análisis moleculares apuntaron hacia la existencia de linajes crípticos dentro de estas especies. El género Scaptotrigona es más diverso de lo esperado, pero aún existen muchos aspectos sobre su diversidad, distribución y biología por estudiar. Esta tesis ha de mostrado el impacto que el manejo tiene en la diversidad de estas especies. Por ello, recomendamos el establecimiento de programas para la conservación de la biodiversidad de las abejas nativas de México y para mejorar la práctica ancestral de la meliponicultura (manejo de las abejas sin aguijón). / Stingless bees (tribe Meliponini) are a group of social insects of the subfamily Apinae with 42 genera and a high number of species, around 500 distributes in the Tropical areas. Within its distribution, the Neotropical area holds the highest diversity. These insects play a key role as generalist pollinators of both wild flora and high economic valuable tropical crops. According to several studies there are evidences pointing to a worldwide decline of bees what is specially accentuated in stingless bees due to their particular biology and their distribution in threaten areas. In this thesis, we have focused on three species from the genus Scaptotrigona distributed in Mexico and northern Guatemala. This genus holds a high diversity with 24 described species and evidences of cryptic species. In order to clarify the taxonomic status of the species S. mexicana, S. pectoralis and S. hellwegeri we have used geometric morphometrics and molecular approaches to define the taxa prone to be conserved. A total of 121 colonies (19 S. hellwegeri, 67 S. mexicana and 35 S. pectoralis) were sampled across their distribution either from wild or managed colonies. From one to six workers per colony were used to screen for wing shape variation, whereas one worker per colony was genotyped with seven polymorphic microsatellite loci. In the first chapter, the DNA barcoding technique has been successfully used to characterize and identify the Scaptotrigona biodiversity in a fast a reliable way. This method suggested the existence of cryptic species within S. mexicana and corroborated previous phylogenetic relationships among the three species. In the second chapter, based on previous evidence of high divergence within Scaptotrigona species, we analyze two species S. mexicana and S. pectoralis with both geometric morphometrics and molecular (microsatellite) methods in order to test the existence of at least two species within S. mexicana, and investigate the species status of S. pectoralis. We found differences with both tools within S. mexicana from Pacific (Sm1) and Atlantic (Sm2) coasts but no differentiation within S. pectoralis. Our results revealed the profile of differentiation of two taxa with S. mexicana, suggesting the need of future taxonomic revisions and activities for management and conservation. In the last chapter, we tested species delimitation through molecular markers by performing further analyses (phylogenetic trees and species discovery with a Bayesian coalescent framework) to confirm the support of the putative species. First, we obtained two different hypotheses of four and six species. After that, the validation of the species hypothesis through an objective analysis that reduces the investigator-driven bias, proposed a four species scenario confirming that S. mexicana is a complex of two species (Sm1 and Sm2) with different distribution (along the Pacific and the Atlantic coasts respectively). We highly recommend to manage them separately avoiding colony exchange in order to conserve both taxa. On the other hand, S. pectoralis and S. hellwegeri remained as on species each but with signs of population differentiation. This thesis has explored the profile of differentiation within the species S. hellwegeri, S. mexicana and S. pectoralis distributed in Mexico and northern Guatemala. Our results of the geometric morphometrics and molecular analyses have pointed the existence of cryptic lineages within this species. The genus Scaptotrigona is more diverse than expected, but different aspects of its diversity, distribution and biology remain to be studied. Furthermore, this work has shown the impact of the management on these bees. Therefore, we recommend establishing programs to conserve the biodiversity of Mexican stingless bees to improve and help the ancient practice of the meliponiculture.

Over the past century there have been substantial declines in farmland biodiversity as a result of the intensification of agricultural practice. Concerns over these declines have led to the development of agri-environment schemes designed to mitigate the effects of intensive agriculture and to benefit biodiversity. Prior to commencing this thesis it was not clear if flower-rich, pollinator-focused agri-environment schemes had a population level impact on wild bees on farmland. Whilst previous work has shown that the creation of flower-rich habitat can provide suitable foraging resources for bumblebees, little was known about the impact of this management on bumblebee population sizes and even less on whether these resources were used by and benefited solitary bees. This thesis compares bee populations between farms with and without flower-rich, pollinator focused agri-environment schemes in Hampshire and West Sussex, UK. Using genetic techniques to estimate colony density, and hence population size, farms implementing targeted schemes had a significantly higher density of bumblebee nests for the four species studied (212 nests/km2 against 112 nests/km2). However, there was no difference in the species richness of bees between these different farm types. When assessing pollen use by solitary bees, flowering plants sown as part of pollinator-focused agri-environment schemes were not widely used, representing 27% of pollen foraging observations and 23% of pollen collected by volume. Only 35% of solitary bee species were found to use sown plants for pollen to a meaningful extent, with most pollen collected from plants persisting in the wider environment. The creation of flower-rich habitat significantly increased resource availability, but did not increase resource diversity. These results indicate that if diverse bee populations are to be maintained on farmland then agri-environment schemes must be developed that effectively increase the number of flowering plant species present at the farm scale.