Michael Philip Schwarz

Michael Philip Schwarz
Flinders University · School of Biological Sciences

About

188
Publications
26,033
Reads
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Introduction
My research career began with (lame) attempts to assess kin selection and sex ratio theories. Along the way I got interested in molecular phylogenetics and comparative approaches, and then historical biogeography and phylogeography. I maintain these interests, but am now also exploring rates of adaptive evolution and how these relate (or don't) to effective population size. My heroes are Motoo Kimura, Tomoko Ohta, John Gillespie and Lawrence Krauss. oh, and Frank Zappa and Hakon Samuelsen.
Additional affiliations
March 1993 - December 2010
Flinders University

Publications

Publications (188)
Article
To understand the earliest stages of social evolution, we need to identify species that are undergoing the initial steps into sociality. Amphylaeus morosus is the only unambiguously known social species in the bee family Colletidae and represents an independent origin of sociality within the Apoidea. This allows us to investigate the selective fact...
Article
The benefits of living in groups drive the evolution of sociality, and these benefits could vary across a life-cycle. However, there may be experimental problems in linking group size at one time in a life-cycle to benefits that only become apparent later on when group size has changed, leading to what we call "temporal dissonance". In the only kno...
Article
Mitochondrial heteroplasmy is the occurrence of more than one type of mitochondrial DNA within a single individual. Although generally reported to occur in a small subset of individuals within a species, there are some instances of widespread heteroplasmy across entire populations. Amphylaeus morosus is an Australian native bee species in the diver...
Article
Full-text available
Adaptive evolutionary theory argues that organisms with larger effective population size (N e) should have higher rates of adaptive evolution and therefore greater capacity to win evolutionary arm races. However, in some certain cases, species with much smaller N e may be able to survive besides their opponents for an extensive evolutionary time. N...
Article
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Understanding how nest parasites contribute to brood mortality rates in host species is an important step towards uncovering the potential implications for host behaviour. This can be especially important for understanding the evolution of social living, where defence against parasites is often posited as a major benefit of cooperative nesting. Onl...
Preprint
Adaptive evolutionary theory argues that organisms with larger effective population size (Ne) should have higher rates of adaptive evolution and therefore greater capacity to win evolutionary arm races. However, in some certain cases species with much smaller Ne may be able to survive beside their opponents for an extensive evolutionary time. Neutr...
Article
There is substantial debate about the relative roles of climate change and human activities on biodiversity and species demographies over the Holocene. In some cases, these two factors can be resolved using fossil data, but for many taxa such data are not available. Inferring historical demographies of taxa has become common, but the methodologies...
Article
Full-text available
The period of the Last Glacial Maximum (LGM) is characterised by severe cooling and extreme aridity in Australia. Australian temperate-adapted bees experienced entirely new conditions over the LGM; however, few studies focused on the response of these key pollinators and their dependent plants to the LGM in Australia. In this study, we investigated...
Article
Full-text available
Super-generalism is a pollinator trait where species obtain floral resources from a very wide range of plant species. Theoretical and empirical studies suggest that on islands with low pollinator diversity, such pollinators should evolve to exploit a very wide range of floral morphologies. Super-generalism has implications not only for securing pol...
Article
Anthropogenic climate change and invasive species are two of the greatest threats to biodiversity, affecting the survival, fitness and distribution of many species around the globe. Invasive species are often expected to have broad thermal tolerances, be highly plastic, or have high adaptive potential when faced with novel environments. Tropical is...
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Low-light adapted bees are substantially understudied components of the bee fauna, particularly in Aus-tralia. Whilst several species in Australia are thought to be adapted to low-light conditions, explicit records of these taxa actually foraging at twilight or night are absent from the scientific literature. We present the first observations of Au...
Article
Gasteruption is an easily recognized genus of wasps whose larvae are predator-inquilines in the nests of cavity-nesting solitary bees (Apidae, Colletidae, Halictidae and Megachilidae), with some records for solitary wasps as hosts (Crabronidae, Vespidae and Sphecidae). There is conflicting information about the biology and host associations for the...
Article
The ability to express different phenotypes can help define species distributions by allowing access to, and exploitation of, new environments. Social insects employ two markedly different reproductive strategies with contrasting cost/benefit characteristics: independent colony foundation (ICF), which is associated with high dispersal range and hig...
Article
Full-text available
Gasteruptiidae Ashmead is an easily recognised family of wasps with circa 589 described species worldwide. Although well characterised by traditional taxonomy, multiple authors have commented on the extreme morphological uniformity of the group, making species-level identification difficult. This problem is enhanced by the lack of molecular data an...
Article
Island biogeography explores how biodiversity in island ecosystems arises and is maintained. The topographical complexity of islands can drive speciation by providing a diversity of niches that promote adaptive radiation and speciation. However, recent studies have argued that phylogenetic niche conservatism, combined with topographical complexity...
Article
The halictine bee genus Homalictus (Apoidea: Halictidae) is distrib- uted broadly across south east Asia, Indonesia, Australia and the archipelagos of the Pacific. The group is well represented in the bee faunas of Australia and Papua New Guinea, but Homalictus is parti- cularly important in the Pacific where it plays a keystone pollination role as...
Article
The Gasteruptiidae are an easily recognised family of wasps whose larvae are considered predator-inquilines in the nests of solitary bees and wasps. There has been minimal molecular research on the family and as a result little understanding of the evolutionary relationships within the group. We present the first molecular phylogeny focused on Gast...
Article
The genus Homalictus Cockerell has not been taxonomically reviewed in the Fijian archipelago for 40 years. Here we redescribe the four known species and describe nine new ones, bringing the number of endemic Homalictus in Fiji to 13 species. We provide identifications keys to all species. Most of the species diversity (11 species) have their distri...
Article
A new mutillid wasp, Ephutomorpha tyla Hearn, Williams & Parslow sp. nov., is described from adult female and male specimens from the Dandenong Ranges in Victoria, Australia. Adult mutillids were repeatedly found in nests of the hylaeine bee Amphylaeus morosus (Smith, 1879) (Hylaeinae) and reared from host nest cells. This represents the first reco...
Article
Full-text available
In isolated islands with low pollinator diversity, it has been suggested that native pollinators should evolve into super-generalists that could facilitate the spread of exotic plant species that might otherwise rely on specialist pollinators. Consequently, in the absence of exotic pollinators isolated islands may still be particularly vulnerable t...
Article
In isolated islands with low pollinator diversity, it has been suggested that native pollinators should evolve into super-generalists that could facilitate the spread of exotic plant species that might otherwise rely on specialist pollinators. Consequently, in the absence of exotic pollinators isolated islands may still be particularly vulnerable t...
Article
Palaeoclimatic events and biogeographical processes since the mid-Tertiary have played an important role in shaping the evolution and distribution of Australian fauna. However, their impacts on fauna in southern and arid zone regions of Australia are not well understood. Here we investigate the phylogeography of an Australian scincid lizard, Tiliqu...
Article
• Species distribution modelling (SDM) has been applied to multiple bee species to examine how they may respond to future climate change. Those studies indicate a variety of likely responses to a warming climate. No SDM approaches, however, have been undertaken for arid‐adapted bees, despite their enormous diversity in xeric habitats. • We applied...
Article
Parasitoid wasps of the subfamily Hyptiogastrinae (Gasteruptiidae) are known to lay eggs in the nests of solitary bees and wasps. Their larvae are considered predator-inquilines, consuming the host’s eggs and larvae and then the nest provisions. Pseudofoenus extraneus is endemic to Fiji, and the only member of the subfamily Hyptiogastrinae known to...
Article
The Australian buzz pollinating bee Amegilla pulchra (Anthophorini) is now widespread in Fiji and represents a potentially major change to plant‐pollinator networks. The introduction of a buzz pollinator into the Fijian ecosystem, which has no native buzz pollinators, may have especially important consequences because many pan‐tropical weed species...
Article
A new Gasteruption Latreille species, G. tomanivi, is described from Viti Levu, Fiji. The new species is the first record of the genus for Fiji and can be distinguished from other Oceanian Gasteruption species by the length of the mesosoma and the large malar space compared with the length of the pedicel. DNA Barcode (mtDNA—COI) sequence is provide...
Article
The taxonomic status of lineages within the Australian allodapine bees has been unstable over the last six decades, with multiple changes in generic and subgeneric assignments. This is unhelpful given the continuing attention to these bees for understanding social evolution and biogeography. The Australian genus Exoneurella (Michener, 1963 Hymenopt...
Article
The success of invading plants in island ecosystems has often been inferred to result from 'invader complexes', where cointroduced plants and their specialist pollinators can reciprocally enhance each other's spread. However, it has also been suggested that in islands with low pollinator diversity, those pollinators should evolve into super-general...
Article
The comparison of social systems, particularly in closely related taxa, can be highly valuable to the understanding of social evolution. While much research has focused on the formation of hierarchies and eusocial organisation, it needs to be remembered that not all social systems are necessarily based on hierarchies. The allodapine bee Exoneurella...
Article
Colletidae is a predominantly southern hemisphere bee family with a Late Cretaceous origin and with an inferred ancestral region covering late Gondwanan South America, Antarctica and Australia. One highly diverse colletid subfamily, Euryglossinae, is entirely restricted to Australia and the strictly Afrotropical subfamily Scrapterinae has been infe...
Article
Facultatively social species exhibit varying degrees of reproductive skew that provide valuable insights into the possible evolutionary forces shaping the origins of obligate eusocial colony organisation, wherein the majority of individuals (workers) forgo direct reproduction. Here we report aspects of the nesting biology of a semi-arid population...
Article
The ability of plants to colonize new habitats is influenced by their dependence on effective pollinators. This can be very important for plants that require specialized pollinators, especially when they disperse to islands that have low pollinator diversity. One form of specialization involves plants that require buzz-pollination, where bees must...
Article
Full-text available
Obligate social parasites of Hymenoptera, known as inquilines, have received enormous attention due to the elaborate adaptations they exhibit for exploiting their hosts, and because they have frequently been used to infer sympatric speciation. Their population biology can be difficult to infer as they are both rare and difficult to extract from hos...
Conference Paper
Full-text available
Earlier studies suggested that organisms with low population size have reduced fitness to handle ecological stress and struggle with their enemies and consequently end up with extinction. However, different studies discovered direct contradicts to this matter. Previous studies in our lab found Allodapine parasite bees as an obvious instance. These...
Article
Island plant–pollinator networks are typically simpler than their continental counterparts and this can make them less resilient to disturbance from exotic species. French Polynesia has a very low diversity of bees, but their status as either native or introduced species has been largely speculative. We combine previous studies with new DNA sequenc...
Article
Full-text available
Recent studies suggest an alarming decline in pollinators across many regions of the world due to multiple factors. One potential factor is climate change, which poses both direct and indirect threats to pollinator popula- tions. To help ameliorate the impact of declining populations on the func- tion of ecological and agricultural systems, there i...
Article
Full-text available
The small carpenter bees, genus Ceratina, are highly diverse, globally distributed, and comprise the sole genus in the tribe Ceratinini. Despite the diversity of the subgenus Neoceratina in the Oriental and Indo- Malayan region, Ceratina (Neoceratina) australensis is the only ceratinine species in Australia. We examine the biogeography and demograp...
Article
Full-text available
Abstract Social parasitism in insects has raised major questions in evolutionary biology, firstly in terms of adaptations that parasites use to circumvent host defenses and, secondly, in terms of whether social parasites have arisen via allopatric or sympatric speciation. Here we raise a third and major evolutionary issue: a priori considerations s...
Article
There has been considerable debate surrounding the evolution of eusociality, which has recently increased in vigor with regard to what actually constitutes eusociality. Surprisingly, there has been little discussion on terminologies for describing social systems that are more-or-less egalitarian, yet such societies form an obvious contrast to eusoc...
Article
Full-text available
Communal behaviour is a form of social behaviour where two or more females nest together and have no reproductive hierarchies. Communal behaviour has often been regarded as an evolutionary ‘stepping stone’ to more complex forms of sociality involving castes, as well as a social form derived from solitary behaviour with no further evolution towards...
Article
Full-text available
How sociality evolves and is maintained remains a key question in evolutionary biology. Most studies to date have focused on insects, birds, and mammals but data from a wider range of taxonomic groups are essential to identify general patterns and processes. The extent of social behaviour among squamate reptiles is under-appreciated, yet they are a...
Article
During the last 150 years, incursions of non-native species have been prevalent throughout the South West Pacific. The allodapine bee, Braunsapis puangensis (Cockerell) (Xylocopinae: Allodapini), was introduced to Fiji between 1965 and 2003, most likely from India. Until very recently, little was known about its dispersal ability and subsequent geo...
Conference Paper
Eusociality is a complex form of social behaviour with colonies comprised of distinct queen and worker castes. Most of the evolutionary origins of this behaviour have been obscured by time, with all extant taxa in those groups displaying eusociality without the original transitional forms. In the Australian Allodapini, however, there is only one kn...
Article
Full-text available
The evolution of social behaviour from solitary antecedents has traditionally been attributed to inclusive fitness benefits. Direct fitness components account for individuals' lifetime reproductive success through the production of offspring. In contrast, indirect fitness components account for the transmission of genes via aiding relatives and may...
Article
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AimInequality between rates of forward and backward dispersal is one mechanism that will produce regional differences in biotic composition. Any such differences will affect ecosystem assembly. Thus, it is important to understand why unequal dispersal rates might occur. Recent studies have indicated strong differences between forward and backward d...
Article
Full-text available
When examining how the ecosystems of remote islands have developed, it is important to know the timing of when various elements arrived and whether they then diversified. Our understanding of the histories behind the biodiverse south west Pacific (SWP) archipelagos is limited, and further impeded by the complex geological histories of this region....
Article
Full-text available
Morphology-based studies have suggested a very depauperate bee fauna for islands in the South West Pacific, and recent genetic studies since have indicated an even smaller endemic fauna with many bee species in this region resulting from human-aided dispersal. These introduced species have the potential to both disrupt native pollinator suites as w...
Article
Full-text available
The impacts of glacial cycles on the geographical distribution and size of populations have been explored for numerous terrestrial and marine taxa. However, most studies have focused on high latitudes, with only a few focused on the response of biota to the last glacial maximum (LGM) in equatorial regions. Here, we examine how population sizes of k...
Article
Full-text available
The islands of the south west Pacific (SWP) are highly biodiverse, yet records of their bee fauna suggest a region depauperate of a key pollinator suite. Studies of the bees of Fiji based on molecular data have revealed a recent origin with the majority of species having arrived since the last glacial maximum or introduced since human colonization....
Article
Full-text available
Circle-tube experiments have been widely used to both examine nestmate recognition in social and solitary insects, as well as to characterise interactions in terms of agonism, cooperation, and avoidance. Despite their use in studies of halictid bees, carpenter bees, adrenid bees, and wasps, they have never been used to explore social interactions i...
Article
Full-text available
Bees and eudicot plants both arose in the mid-late Cretaceous, and their co-evolutionary relationships have often been assumed as an important element in the rise of flowering plants. Given the near-complete dependence of bees on eudicots we would expect that major extinction events affecting the latter would have also impacted bees. However, given...
Article
Full-text available
INTRODUCTION: Australia has the most unusual bee fauna in the world (Michener 1965), but the nesting biology and behaviour of our bees has been studied for only a very small proportion of species. The only Australian native bees that live in hives are the stingless bees (tribe Meliponini) and these are restricted to the northern half of Australia....
Article
The evolutionary origins of social parasitism are very unevenly distributed among ants, bees and wasps, but social parasite lineages are frequently close relatives of their host lineages. Two explanations for these relationships have been proposed: (1) initially, social species are more likely to become parasitic on relatively closely related socia...
Article
Although bees form a key pollinator suite for flowering plants, very few studies have examined the evolutionary radiation of non-domesticated bees over human time-scales. This is surprising given the importance of bees for crop pollination and the effect of humans in transforming ecosystems via agriculture. In the Pacific, where the bee fauna appea...
Article
Full-text available
Abstract Bees are key pollinators in almost all terrestrial ecosystems, and can have major roles in agricultural production. Records of bees in the south west pacific (SWP) indicate a very low diversity, with the Fijian bee fauna one of the least diverse, despite an otherwise rich biota. Megachilid bees represent a large proportion of the bee fauna...
Article
Full-text available
Bees are key pollinators in almost all terrestrial ecosystems, and can have major roles in agricultural production. Records of bees in the south west pacific (SWP) indicate a very low diversity, with the Fijian bee fauna one of the least diverse, despite an otherwise rich biota. Megachilid bees represent a large proportion of the bee fauna for almo...
Data
Phytophagous insects that specialise on broadly distributed plant groups are exposed to host‐species diversity gradients. The gall‐inducing thrips genus Kladothrips (Froggatt) that specialise on Australian Acacia Mill. (Mimosoideae: Leguminosae, subgenus Phyllodineae DC.) is expected to exhibit variation in host range that is dependent on host ecol...
Data
Full-text available
The diversification of gall-inducing Australian Kladothrips (Insecta: Thysanoptera) on Acacia has produced a pair of sister-clades, each of which includes a suite of lineages that utilize virtually the same set of 15 closely related host plant species. This pattern of parallel insect-host plant radiation may be driven by cospeciation, host-shifting...
Conference Paper
Full-text available
The bee tribe Allodapini is unique in the large number of times that social parasitism has evolved within it – more times than all other bees and wasps combined. These multiple origins provide unrivalled material for understanding co-speciation between hosts and social parasites, as well as exploring speciation mechanisms per se and deeper issues o...
Article
Hylaeus is the only globally distributed colletid bee genus, with subgeneric and species-level diversity highest in Australia. We used one mitochondrial and two nuclear genes to reconstruct a phylogeny using Bayesian analyses of this genus based on species from Australia, Asia, Africa, Europe, Hawai'i, the New World and New Zealand. Our results con...
Article
Understanding how social species differentially allocate reproduction within groups is a major problem in evolutionary biology. A key issue is whether relatedness among nestmates can be assessed by group members and then used to determine levels of skew. Several studies have shown a relationship between skew and relatedness, but this might indicate...
Article
Full-text available
The origin of sterile worker castes, resulting in eusociality, represents one of the major evolutionary transitions in the history of life. Understanding how eusociality has evolved is therefore an important issue for understanding life on earth. Here we show that in the large bee subfamily Xylocopinae, a simple form of sociality was present in the...
Data
Consensus phylogeny obtained from the BayesPhylogenies analysis, along with posterior probabilities for all nodes. (DOCX)
Data
Genbank accession numbers and social status and references for this status for Xylocopinae species in our study. (DOC)
Data
Chronogram obtained from a penalised likelihood transformation of the consensus phylogram obtained from a MrBayes analysis. (DOC)