Evolution Of Bees Research Articles

Quantitative pollen requirements of solitary bees: Implications for bee conservation and the evolution of bee–flower relationships

Knowledge about the quantitative pollen requirements of solitary bees is crucial for the preservation of endangered bee species and the understanding of the evolution of bee–flower relationships. We estimate the number of flowers required to rear a single larva for 41 European bee species (i) by comparing the pollen content of brood cells with the pollen quantity contained in the flowers of the bees’ host plants and (ii) by deducing the pollen requirements from a regression model describing the relationship between the average bee dry body mass and the average brood cell pollen content. The flower requirements of the bee species examined vary by three orders of magnitude. Depending on both bee species and host plant, from seven to 1100 flowers or from 0.9 to 4.5 flower heads are needed to rear a single larva. As only about 40% of the pollen contained in a flower was found to be available to a single female bee, these minimal figures have to be multiplied by a factor of approximately 2.5 to obtain a realistic estimate of bee flower requirements. The amount of pollen lost from flowers for bee nutrition is surprisingly high. We hypothesize that the recent decline of many bee species may have its main cause in a food shortage provoked by a decrease in flower diversity and quantity following habitat destruction and modern agricultural practices. The substantial pollen losses to bees as documented in this study support earlier findings on floral adaptations against excessive pollen harvesting by bees.

Mitochondrial tRNA gene translocations in highly eusocial bees

Mitochondrial gene rearrangement events, especially involving tRNA genes, have been described more frequently as more complete mitochondrial genome sequences are becoming available. In the present work, we analyzed mitochondrial tRNA gene rearrangements between two bee species belonging to the tribes Apini and Meliponini within the "corbiculate Apidae". Eleven tRNA genes are in different genome positions or strands. The molecular events responsible for each translocation are explained. Considering the high number of rearrangements observed, the data presented here contradict the general rule of high gene order conservation among closely related organisms, and also represent a powerful molecular tool to help solve questions about phylogeny and evolution in bees.

Roles of hierarchical and metabolic regulation in the allometric scaling of metabolism in Panamanian orchid bees

Assessment of the relative importance of variation in enzyme concentration [E] and metabolic regulation in accounting for interspecific variation in metabolic rates is an unrealized area of research. Towards this end, we used metabolic flux rates during hovering and enzymatic flux capacities (V(max) values, equal to [E]xk(cat), where k(cat) is catalytic efficiency) in flight muscles measured in vitro from 14 orchid bee species ranging in body mass from 47 to 1065 mg. Previous studies revealed that, across orchid bee species, wingbeat frequencies and metabolic rates decline in parallel with increasing body mass. V(max) values at some enzymatic steps in pathways of energy metabolism decline with increasing mass while, at most other steps, V(max) values are mass-independent. We quantified the relative importance of ;hierarchical regulation' (alteration in V(max), indicative of alteration in [E]) and ;metabolic regulation' (resulting from variation in substrate, product or modulator concentrations) in accounting for interspecific variation in flux across species. In addition, we applied the method of phylogenetically independent contrasts to remove the potentially confounding effects of phylogenetic relationships among species. In the evolution of orchid bees, hierarchical regulation completely accounts for allometric variation in flux rates at the hexokinase step while, at other reactions, variation in flux is completely accounted for by metabolic regulation. The predominant role played by metabolic regulation is examined at the phosphoglucoisomerase step using the Haldane relationship. We find that extremely small variation in the concentration ratio of [product]/[substrate] is enough to cause the observed interspecific variation in net flux at this reaction in glycolysis.

Phylogeny, historical biogeography, and character evolution in bumble bees ( Bombus: Apidae) based on simultaneous analysis of three nuclear gene sequences

Phylogeny, historical biogeography, and character evolution in bumble bees ( Bombus: Apidae) based on simultaneous analysis of three nuclear gene sequences

Evidence from multiple gene sequences indicates that termites evolved from wood-feeding cockroaches.

Despite more than half a century of research, the evolutionary origin of termites remains unresolved [1] [2] [3]. A clear picture of termite ancestry is crucial for understanding how these insects evolved eusociality, particularly because they lack the haplodiploid genetic system associated with eusocial evolution in bees, ants, wasps and thrips [4] [5]. Termites, together with cockroaches and praying mantids, constitute the order Dictyoptera, which has been the focus of numerous conflicting phylogenetic studies in recent decades [6] [7] [8] [9] [10] [11] [12]. With the aim of settling the debate over the sister-group of termites, we have determined the sequences of genes encoding 18S ribosomal RNA, mitochondrial cytochrome oxidase subunit II (COII) and endogenous endo-beta-1, 4-glucanase (EG) from a diverse range of dictyopterans. Maximum parsimony and likelihood analyses of these sequences revealed strong support for a clade consisting of termites and subsocial, wood-feeding cockroaches of the genus Cryptocercus. This clade is nested within a larger cockroach clade, implicating wood-feeding cockroaches as an evolutionary intermediate between primitive non-social taxa and eusocial termites.

Phylogeographical autocorrelation of phenotypic evolution in honey bees (Apis mellifera L.).

The analysis of phenotypic divergence among local populations within a species has been traditionally performed in a spatial context, although advances in genetic analysis using mtDNA have permitted a simultaneous evaluation of geographical and historical patterns of variation, so-called phylogeographical analysis. In this paper, we combine these two dimensions of variation (geographical space and phylogenetic history) to evaluate patterns of phenotypic evolution in honey bees (Apis mellifera L.). Data on 39 phenotypic traits, derived from 417 colonies grouped into 14 subspecies, were analysed using autocorrelation methods. Mantel tests indicated that the relationship between phenotypic divergence, estimated by Euclidean distances among subspecies' morphological centroids, was significant both when compared to geographical distance (r=0.371; P < 0.01) and to genetic distance (estimated as sequence divergence (%) in a mtDNA region encompassing part of the NADH dehydrogenase subunit 2 and isoleucine transfer RNA (r=0.329; P < 0.01)). For the analysis of each trait, the effects of the geographical co-ordinates (latitude and longitude of subspecies geographical range) and of the phylogenetic patterns (defined by eigenvectors of the genetic distance matrix) on phenotypic variation were simultaneously analysed using an extension of a recently developed model, called Phylogenetic Eigenvector Regression (PVR). In general terms, the partial regression slopes indicated that the variation in the characters traditionally associated with adaptive processes, such as body and wing size, were better explained by geographical position. However, characters usually thought to be neutral, such as wing venation angle, were more associated with phylogeny. This is expected because PVR can be interpreted as a partition model, in which adaptive variation tends to be independent of phylogeny (and, in this case, associated with geography). In addition, the first principal component derived from the expected values of the model for each trait, which can be interpreted as the phenotypic variation predicted by phylogeny, is more structured in a north-south cline than are the original data, supporting an adaptive interpretation. The phylogeographical autocorrelation analyses performed in this study show that different traits are more related to one of the two dimensions of variation (geography and phylogeny), and these patterns can furnish insights into the nature of phenotypic evolution in these organisms.

Phylogeographical autocorrelation of phenotypic evolution in honey bees (Apis mellifera L.)

The analysis of phenotypic divergence among local populations within a species has been traditionally performed in a spatial context, although advances in genetic analysis using mtDNA have permitted a simultaneous evaluation of geographical and historical patterns of variation, so-called phylogeographical analysis. In this paper, we combine these two dimensions of variation (geographical space and phylogenetic history) to evaluate patterns of phenotypic evolution in honey bees (Apis mellifera L.). Data on 39 phenotypic traits, derived from 417 colonies grouped into 14 subspecies, were analysed using autocorrelation methods. Mantel tests indicated that the relationship between phenotypic divergence, estimated by Euclidean distances among subspecies’ morphological centroids, was significant both when compared to geographical distance (r=0.371; P< 0.01) and to genetic distance (estimated as sequence divergence (%) in a mtDNA region encompassing part of the NADH dehydrogenase subunit 2 and isoleucine transfer RNA (r=0.329; P< 0.01)). For the analysis of each trait, the effects of the geographical co-ordinates (latitude and longitude of subspecies geographical range) and of the phylogenetic patterns (defined by eigenvectors of the genetic distance matrix) on phenotypic variation were simultaneously analysed using an extension of a recently developed model, called Phylogenetic Eigenvector Regression (PVR). In general terms, the partial regression slopes indicated that the variation in the characters traditionally associated with adaptive processes, such as body and wing size, were better explained by geographical position. However, characters usually thought to be neutral, such as wing venation angle, were more associated with phylogeny. This is expected because PVR can be interpreted as a partition model, in which adaptive variation tends to be independent of phylogeny (and, in this case, associated with geography). In addition, the first principal component derived from the expected values of the model for each trait, which can be interpreted as the phenotypic variation predicted by phylogeny, is more structured in a north–south cline than are the original data, supporting an adaptive interpretation. The phylogeographical autocorrelation analyses performed in this study show that different traits are more related to one of the two dimensions of variation (geography and phylogeny), and these patterns can furnish insights into the nature of phenotypic evolution in these organisms.

Phylogeny and Behavior in Honey Bees (Hymenoptera: Apidae)

Methods for distinguishing phylogenetic signal from noise are employed to resolve conflicting phylogenies produced by 3 separate morphological and molecular data sets for the 6 species of the honey bee genus Apis . Morphological data from larvae are employed for the 1st time. The results support the phylogeny produced by separate analyses of the morphological and mitochondrial 16s ribosomal DNA (rDNA) data sets, and contradict the result produced by the mitochondrial COII data set. Additionally, these results support previous conclusions that 16s rDNA sequence data are more informative for species-level rather than tribal-level relationships in the corbiculate bees. Resolution of Apis phylogeny permits for the 1st time unambiguous reconstruction of the ancestral states for several important behavioral characters in honey bee evolution.

Pollen in Bee‐Flower Relations Some Considerations on Melittophily*

Abstract:Pollen and nectar are usually lumped together as floral rewards for pollinating bees, but they play totally different roles for flowers and bees (Table 1), as well as in the relationship between them. While flowers are specialized for certain pollinators via nectar, bees specialize on certain flowers via pollen. While flowers need pollen as a prerequisite for pollination, it is the essential larval food in bees. Thus, there is a strong competition between them for pollen. Foraging for pollen must be divided into three phases: uptake in the flower, reloading into and homeward transport within a carrying container. Bees have specializations for transport but hardly any for pollen uptake ‐ and thus for pollination. Bees actively harvesting pollen usually do not pollinate. This only happens as a consequence of contamination of the bee by pollen. From these data a scenario is provided for the evolution of bees and bee flowers. Specialized bee flowers are often characterized by their ability to hide pollen from the bees and at the same time use them as optimal pollinators. If the relationship of bees and flowers is mutualistic at all it is best described as a balanced mutual exploitation.

Population Genetics, Diploid Males, and Limits to Social Evolution of Euglossine Bees

Population Genetics, Diploid Males, and Limits to Social Evolution of Euglossine Bees

Morphological Specializations in Central European Bees for the Uptake of Pollen from Flowers with Anthers Hidden in Narrow Corolla Tubes (Hymenoptera: Apoidea)

13 species of the Central European bee fauna belonging to 4 familiae and 5 genera were found to have evolved stout, curved bristles either on the tarsomera of pedes-I [P-I-ta] or on the proboscis which serve to extract pollen from plants having their anthers enclosed in narrow flower tubes, viz representatives of the Boraginaceae and Primulaceae. Pollen from narrow-tubed flowers plays an important role in the larval nourishment of these bees. The development of hooked bristles on the P-I-ta of one bee species is accompanied by a distinct elongation of the pedes-I which is interpreted as an additional adaptation to anthers concealed in deep corolla tubes. A literature survey reveals that morphological specializations enabling female bees to collect pollen efficiently at narrow-tubed flowers are widespread and must have evolved many times during bee evolution. The currently known morphological specializations of bees for the uptake of pollen from flowers are reviewed.

Biology of the stingless beePlebeia remota (Holmberg): observations and evolutionary implications

The genusPlebeia has a special significance for the study of social evolution of stingless bees: morphologically primitive, its species display a wealth of behavioural evolution, especially with respect to the oviposition process. We comparePlebeia remota with the few other members of the genus studied so far. Related to its subtropical geographical range, brood production is seasonal (there is no brood in the colony in colder months), and adult workers occur as summer and winter bees. The nest is in tree cavities, and the involucrum is absent or restricted to the winter period. Brood cells are arranged in horizontal combs, and new cells are built completely synchronously. Each series consists of up to 50 cells, their number being mainly dependent on colony size. Construction speed is remarkably constant, allowing 4–6 batches per 24 hours. Cell building and provisioning are activities of a small group of specialized workers. The oviposition cycle follows the classical subdivisions for stingless bees. During the patrolling phase a worker may “offer” a trophic egg in a most remarkable way: while retreating backward from the queen she bends the abdomen under thorax and head, and lays an egg on the comb. This egg is eaten by the queen or a worker. The provisioning, oviposition and operculation of all cells occur simultaneously, each cell is provisioned by 4–9 workers. Localization of a cell by the queen may be facilitated by its characteristic guard, which “defends” the cell against the approaching queen. The degree of synchronization within a batch is very high: the duration per cell lasts 420–950 sec, the batch of up till 50 cells needs only 557–1160 sec. Operculation is done by a worker that was not involved in the previous steps. Males are generally produced by the queen. Several male producing cycles per year occur. In orphan colonies laying workers give rise to males, and in queenright colonies workers may occasionally reproduce as well. Division of labour follows the general pattern for stingless bees; however, cell building and provisioning are activities of a specialized group of workers.

Replacing the terms 'primitive' and 'advanced': new modifiers for the term 'eusocial'

The comparative method relies not only on a good understanding of the phylogenetic relationships among taxa, but also on consistent terminology for describing phenotypes. Clear and consistent terminology allows similar phenotypes to be described and phylogenetically analyzed in different organisms, whereas inconsistent terminology is a major impediment to comparisons, even for taxonomically restricted groups such as bees. Here, I propose that the usefulness of social terminology can be judged by its value in phylogenetic trait-mapping aimed at uncovering evolutionary transitions between solitary and social behavior. I propose a four-step approach to evaluate and update social terminology, in which definitions are first updated based on recent behavioral studies (step 1), mapped onto a phylogeny (step 2), evaluated for their utility in the trait-mapping exercise (step 3), and then, if necessary, revised (step 4). To demonstrate the approach, I define four terms important for understanding social evolution in bees (solitary, social, eusocial, and hypersocial) and map them onto a very recent phylogeny of Apidae. This not only illustrates an objective method for evaluating social terminology, but also provides novel inferences about social evolution in Apidae, including support for a parasocial origin of eusociality and at least two Major Evolutionary Transitions to hypersociality.

The oldest fossil bee: Apoid history, evolutionary stasis, and antiquity of social behavior

Trigona prisca, a stingless honey bee (Apidae; Meliponinae), is reported from Cretaceous New Jersey amber (96-74 million years before present). This is about twice the age of the oldest previously known fossil bee, although Trigona is one of the most derived bee genera. T. prisca is closely similar to modern neotropical species. Most of bee evolution probably occurred during the approximately 50 million years between the beginning of the Cretaceous when flowering plants (on which bees depend) appeared and the time of T. prisca. Since then, in this phyletic line of Meliponinae, there has been almost no morphological evolution. Since the fossil is a worker, social organization had arisen by its time.

Advances in Cytology and Genetics of Bees

Seven previous papers have reviewed the genetics, cytology, and evolution of bees (33, 37, 41, 59, 60, 63, 64). As is the case in every field of science good progress in bee genetics is being made, not only by those whose contributions deal directly with bees but also by those whose interest is in other Hymenoptera (15, 26, 69) and whose studies have an indirect but important impact on our understanding of the genetics of bees.

POLLINATION BIOLOGY OF NEMOPHILA MENZIESII (HYDROPHYLLACEAE) WITH COMMENTS ON THE EVOLUTION OF OLIGOLECTIC BEES.

The interaction between plants and extremely diverse habitats and environmental conditions of California has resulted in rapid evolution in many plant groups. A small number of studies suggest that evolution in many of these groups has been accompanied and perhaps paralleled by evolution in particular groups of bees (Linsley and MacSwain, 1957, 1959; Linsley et al., 1963a, 1963b; 1964; Thorp, 1969). The interaction between these bees and their pollen plants is oligolectic. An oligolectic relationship is defined by Linsley and MacSwain (1957, 1958) as one . . in which the individual members of the population, throughout its range and in the presence of other pollen sources, consistently and regularly collect pollen from but a single plant species or from a group of similar or related plant species, turning to other sources, if at all, only when there is a local shortage or absence of that pollen. Oligolectic relationships may be nonselective or co-evolved. Included in the first class are Andrena linsleyi Timberlake, which collects pollen of Oenothera deltoides Torr. and Frem. in the morning after sphinx-moths have pollinated the flowers (Linsley et al., 1963; Gregory, 1964), and Andrena nemophilae Ribble which is discussed below. Such a bee must adapt to the evolutionary vicissitudes of the flower and its pollinator(s). The second class includes those bees which are pollinators of the host plant. Thus they may influence the evolution of the plant as well as being influenced by the plant. This group of bees and their pollen plants are of particular interest to the student of pollination biology and evolution. Although a number of studies have dealt with oligolectic bees, the basis of the relationship remains an enigma. The flight period of most oligolectic bees is short and the adult bee's only previous contact with a particular pollen source is the pollen and nectar it consumed as a larva. Three explanations have been suggested to explain oligolecty. First, it is genetically controlled (Thorp, 1969). Second, a preimaginal conditioning from the pollen and nectar that the larva consumes (Linsley, 1958). Third, some combination of the above, i.e., genetical control modified by conditioning (Thorp, 1969). In this paper my objectives are (1) to present a broad picture of the plant Nemophila menziesii H. and A. s.l. and its pollinators and (2) to re-examine particular questions concerning evolution within oligolectic bees. Specifically, I discuss the distribution, floral behavior and breeding system of the plant, Nemophila as a bee plant, the oligolectic Nemophila bees, the role of polylectic bees in pollination, and fly pollination. In the final section I discuss host plant recognition and evolution in oligolectic bees

Karyotypic Evolution of Bees and Corresponding Taxonomic Implications

Karyotypic Evolution of Bees and Corresponding Taxonomic Implications

The ecology of solitary bees

Bees play an important and necessary role in the pollination of agricultural crops grown for fruit and seed and of forage and browse plants important in range management for production of both livestock and game animals. Nearly 20,000 different kinds of bees are now known, some, like the imported honey bee, the bumble bees, and the stingless bees of the tropics, are social and live together in colonies subject to manipulation and movement from place to place. However, by far the majority of bees are solitary, living in burrows in the ground, in wood, or in plant stems, where they store pollen and nectar as food for their young. Many of these take pollen only from certain kinds of plants and are very efficient pollinators of these. Others, like the honey bee, visit a wide variety of pollen plants, both native and introduced. Although management procedures have been developed for certain crops in certain areas which permit the effective use of honey bees for increased production through better pollination, these are not universally applicable to our agriculture as a whole. For certain crops, both cultivated and wild, supplemental pollination is necessary. The development of management procedures which will permit increased utilization of native solitary bees and perhaps lead to the importation of foreign species native to the areas in which our agricultural crops originated, requires a detailed knowledge of the ecology, or environmental relationships, of these bees. This article is intended to review as briefly as possible, the current status of our knowledge of the subject and to indicate published papers in which various aspects may be pursued further. Prominence has been given to publications of the last fifteen years and to those which are most comprehensive and include references to earlier literature. Factors which appear to have had an influence in the economy, evolution, and survival of solitary bees have been especially emphasized.

THE EVOLUTION OF CUCKOO BEES AND WASPS

Journal Article THE EVOLUTION OF CUCKOO BEES AND WASPS Get access O. W. Richards O. W. Richards Search for other works by this author on: Oxford Academic Google Scholar Proceedings Linnean Society London, Volume 161, Issue 1, July 1949, Pages 40–41, https://doi.org/10.1111/j.1095-8312.1949.tb00537.x Published: 09 April 2009