Jeff Ollerton

University of Northampton | UN · Faculty of Arts, Science and Technology

Animal pollination is a vital ecological process in both natural and agricultural ecosystems. Economic valuation studies have demonstrated that pollination services may underpin a significant proportion of global crop market outputs. However these assessments are probably under-estimates because they have rarely included nonfood crops, for which ve...

Background and aims: Modularity is a ubiquitous and important structural property of ecological networks which describes the relative strengths of sets of interacting species and gives insights into the dynamics of ecological communities. However, this has rarely been studied in species-rich, tropical plant-pollinator networks. Working in a biodiv...

The apparent reduction of solitary and primitively eusocial bees populations has remained a huge concern over the past few decades and urbanisation is considered as one of the factors affecting bees at different scales depending on bee guild. As urbanisation is increasing globally it necessitates more research to understand the complex community dy...

Pollinators are fundamental to maintaining both biodiversity and agricultural productivity, but habitat destruction, loss of flower resources, and increased use of pesticides are causing declines in their abundance and diversity. Using historical records, we assessed the rate of extinction of bee and flower-visiting wasp species in Britain from the...

Plant‐pollinator interactions exist along a continuum from complete specialisation to highly generalised, that may vary in time and space. A long‐held assumption is that large bees are usually the most effective pollinators of generalist plants. We tested this by studying the relative importance of different groups of pollinators of Knautia arvensi...

Communicating results and ideas to a wider audience has been an important, but challenging component of scientists working in an academic environment. Particularly in recent decades, various social media platforms have become increasingly important to facilitate this. In addition, many scientists have used blogging platforms to communicate and disc...

Many studies seeking to understand the success of biological invasions focus on species’ escape from negative interactions, such as damage from herbivores, pathogens, or predators in their introduced range (enemy release). However, much less work has been done to assess the possibility that introduced species might shed mutualists such as pollinato...

The East African lowland honey bee ( Apis mellifera scutellata ) is reported as an aggressive subspecies of the Western honey bee, but few studies have investigated the impact of its aggressiveness on other insect pollinators. Observations of flower visitors to Vachellia ( Acacia ) etbaica and interactions between honey bees and other insects were...

The chequered skipper butterfly Carterocephalus palaemon was reintroduced to Fineshade Wood, England in 2018 as part of a Butterfly Conservation-led project following several years of planning. From 2019–2022, the population was sampled each May–June by the lead author, timed count volunteers, Butterfly Conservation staff, and casual observers. A n...

Plant-pollinator interactions play a vital role in the maintenance of biodiversity and ecosystem function. Geographical variation in environmental factors can influence the diversity of pollinators and thus, affect the structure of pollination networks. Given the current global climate change, understanding the variation of pollination network stru...

The WorldFAIR Case Study on Agricultural Biodiversity (WP10) addresses the challenges of advancing interoperability and mobilising plant-pollinator interactions data for reuse. Previous efforts, reported in Deliverable 10.1 - from our discovery phase - provided an overview of projects, best practices, tools, and examples for creating, managing and...

Meeting ambitions such as the Global Biodiversity Framework 2030 targets will require multiple conservation mechanisms that benefit the widest possible range of habitats and species. Using England as a case study, here we evaluate the likely impact of a novel and ambitious ecological compensation policy, Biodiversity Net Gain (BNG), on terrestrial...

Animal pollination is important for more than 75% of agricultural crops, including coffee, whose productivity can increase with adequate pollination. Bees, including many solitary species, are diverse pollinators, with around 85% of them considered more effective than honeybees in pollen transfer. We assessed the coffee plantation and its surroundi...

COMING LATER THIS YEAR: Most people are familiar with hummingbirds and the balletic ways in which they feed on flowers. But did you know that these kinds of relationships first evolved at least 50 million years ago? And that nowadays at least 64 families of birds include species that act as pollinators, for tens of thousands of different plants? N...

Solitary and primitively eusocial bees, an important group of pollinators, have declined in the past few decades. In view of the recent focus on safeguarding pollinating insects, it is vital to understand the basic ecology of species for their conservation, for example their phenologies. We observed the flight periods of solitary and primitively eu...

A new species of Lygistorrhina (Lygistorrhina) Skuse, 1890, Lygistorrhina woodi sp. nov., is described. The specimen was dissected from an alcohol-preserved flower of Ceropegia aristolochioides ssp. deflersiana Bruyns (Apocynaceae, Asclepiadoideae, Ceropegieae) stored in the Kew herbarium. This is the first occurrence of the lygistorrhine gnats in...

Insect pollinator biodiversity is changing rapidly, with potential consequences for the provision of crop pollination. However, the role of land use–climate interactions in pollinator biodiversity changes, as well as consequent economic effects via changes in crop pollination, remains poorly understood. We present a global assessment of the interac...

When a plant is introduced to a new ecosystem it may escape from some of its coevolved herbivores. Reduced herbivore damage, and the ability of introduced plants to allocate resources from defence to growth and reproduction can increase the success of introduced species. This mechanism is known as enemy release and is known to occur in some species...

Although pollination is an essential ecosystem service that sustains life on Earth, data on this vital process is largely scattered or unavailable, limiting our understanding of the current state of pollinators and hindering effective actions for their conservation and sustainable management. In addition to the well-known challenges of biodiversity...

Bees provide important ecological services, and many species are threatened globally, yet our knowledge of wild bee ecology and evolution is limited. While evolving from carnivorous ancestors, bees had to develop strategies for coping with limitations imposed on them by a plant‐based diet, with nectar providing energy and essential amino acids and...

When a plant is introduced to a new ecosystem it may escape from some of its coevolved herbivores. Reduced herbivore damage, and the ability of introduced plants to allocate resources from defence to growth and reproduction can increase the success of introduced species. This mechanism is known as enemy release and is known to occur in some species...

Pollination is the process that ensures the reproduction, survival, and evolution of plants through time, which is essential for sustaining life in ecosystems. Different external pollen vectors can carry grains to the female reproductive organs, such as wind, water, animals, or a mixture of these. Unlike today, gymnosperms dominated the land surfac...

Abstract. Inferring insect pollination from compression fossils and amber inclusions is difficult because of a lack of consensus on defining an insect pollinator and the challenge of recognizing this ecological relationship in deep time. We propose a conceptual definition for such insects and an operational classification into pollinator or presume...

Identifying large-scale patterns of variation in pollinator dependence (PD) in crops is important from both basic and applied perspectives. Evidence from wild plants indicates that this variation can be structured latitudinally. Individuals from populations at high latitudes may be more selfed and less dependent on pollinators due to higher environ...

Plant-pollinator studies are increasingly using network analysis to investigate the structure and function of such communities. However, many areas of high diversity largely remained unexplored in this way. Our study describes a plant-pollinator meta-network from an overlooked biodiversity hotspot, the Kashmir Himalaya, where we specifically invest...

Introduced species often benefit from escaping their enemies when they are transported to a new range, an idea commonly expressed as the enemy release hypothesis. However, species might shed mutualists as well as enemies when they colonize a new range. Loss of mutualists might reduce the success of introduced populations, or even cause failure to e...

Bipartite networks of flowering plants and their visitors (potential pollinators) are increasingly being used in studies of the structure and function of these ecological interactions. Whilst they hold much promise in understanding the ecology of plant–pollinator networks and how this may be altered by environmental perturbations, like land-use cha...

Food system resilience has multiple dimensions. We draw on food system and resilience concepts and review resilience framings of different communities. We present four questions to frame food system resilience (Resilience of what? Resilience to what? Resilience from whose perspective? Resilience for how long?) and three approaches to enhancing resi...

Food system resilience has multiple dimensions. We draw on food system and resilience concepts and review resilience framings of different communities. We present four questions to frame food system resilience (Resilience of what? Resilience to what? Resilience from whose perspective? Resilience for how long?) and three approaches to enhancing resi...

Biodiversity is declining through human activities and urbanisation is often seen as a particular concern. Urban settings, however, provide diverse microclimatic conditions for plants and pollinating insects, and therefore may be significant habitats for the conservation of solitary and primitively eusocial bees, a major group of pollinators. This...

Determining when animal populations have experienced stress in the past is fundamental to understanding how risk factors drive contemporary and future species' responses to environmental change. For insects, quantifying stress and associating it with environmental factors has been challenging due to a paucity of time‐series data and because detecta...

Insect declines are a global issue with significant ecological and economic ramifications. Yet, we have a poor understanding of the genomic impact these losses can have. Genome‐wide data from historical specimens have the potential to provide baselines of population genetic measures to study population change, with natural history collections repre...

The sexual reproduction of seed plants involves the transfer of male gametes—in pollen—to their female gametes. In flowering plants (angiosperms), this is performed with the stigma of flowers, whereas the gymnosperms (such as conifers and cycads) produce a diversity of structures on their reproductive axes to accomplish the same task. This transfer...

During the main COVID-19 global pandemic lockdown period of 2020 an impromptu set of pollination ecologists came together via social media and personal contacts to carry out standardised surveys of the flower visits and plants in gardens. The surveys involved 67 rural, suburban and urban gardens, of various sizes, ranging from 61.18° North in Norwa...

Aim Aggregated species occurrence data are increasingly accessible through public databases for the analysis of temporal trends in the geographic distributions of species. However, biases in these data present challenges for statistical inference. We assessed potential biases in data available through GBIF on the occurrences of four flower‐visiting...

Biotic interactions are said to be more specialized in the tropics, and this was also proposed for the pollination systems of columnar cacti from North America. However, this has not yet been tested for a wider set of cactus species. Here, we use the available information about pollination in the Cactaceae to explore the geographic patterns of this...

The chequered skipper butterfly Carterocephalus palaemon (Pallas, 1771) was declared extinct in England in 1976 after suffering a precipitous decline in range and abundance during the 20th Century. By searching and collating museum and other records, we show how a deeper understanding of this decline can be achieved, thus furthering conservation ob...

Pollinator declines have prompted efforts to assess how land‐use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape‐scale data and technical expertise. In expert workshops, 3 straightforward methods (desk‐based method, field surve...

Since Darwin, very long and narrow floral tubes have been known to represent the main floral morphological feature for specialized long‐tongued hawkmoth pollination. However, specialization may be driven by other contrivances instead of floral tube morphology. Asclepiads are plants with a complex floral morphology where primary hawkmoth pollination...

Aim: Aggregated species occurrence data are increasingly accessible through public databases for the analysis of temporal trends in species’ distributions. However, biases in these data present challenges for robust statistical inference. We assessed potential biases in data available through GBIF on the occurrences of four flower-visiting taxa: be...

Heterospecific pollen deposition (HPD) is ubiquitous across plant communities, especially for generalized species which use a diversity of pollinators, and may have negative effects on plant reproduction. However, it is unclear whether temporal changes in the co-flowering community result in changes in HPD patterns. Moreover, community-level studie...

Urbanisation is a prominent and increasing form of land-use change, with the potential to disrupt the interactions between pollinators such as bees and the flowering plants that they visit. This in turn may cause cascading local extinctions and have consequences for pollination services. Network approaches go beyond simple metrics of abundance and...

In the last decade there has been a massive rise in the number of animals being sold via online classified websites, with herpetofauna (reptiles and amphibians) being no exception. In response to growing concerns regarding irresponsible advertising, the Pet Advertising Advisory Group (PAAG) was established to ensure animals are sold legally and eth...

The European honeybee Apis mellifera is a highly successful, abundant species and has been introduced into habitats across the globe. As a supergeneralist species, the European honeybee has the potential to disrupt pollination networks, especially in Australia, whose flora and fauna have co-evolved for millions of years. The role of honeybees in po...

Pollinating species are in decline globally, with land use an important driver. However, most of the evidence on which these claims are made is patchy, based on studies with low taxonomic and geographic representativeness. Here, we model the effect of land-use type and intensity on global pollinator biodiversity, using a local-scale database coveri...

Pollinators have a critical, but largely unappreciated, role to play when it comes to climate change, says Jeff Ollerton

A unique and personal insight into the ecology and evolution of pollinators, their relationships with flowers, and their conservation in a rapidly changing world. The pollination of flowers by insects, birds and other animals is a fundamentally important ecological function that supports both the natural world and human society. Without pollinators...

Patterns in ecology are the products of current factors interacting with history. Nevertheless, few studies have attempted to disentangle the contribution of historical and current factors, such as climate change and pollinator identity and behavior, on plant reproduction. Here, we attempted to separate the relative importance of current and histor...

A unique and personal insight into the ecology and evolution of pollinators, their relationships with flowers, and their conservation in a rapidly changing world. The pollination of flowers by insects, birds and other animals is a fundamentally important ecological function that supports both the natural world and human society. Without pollinator...

PREMISE: Species of Apocynaceae are pollinated by a diverse assemblage of animals. Here we report the frst record of specialized cockroach pollination in the family, involving an endangered climbing vine species, Vincetoxicum hainanense in China. Experiments were designed to provide direct proof of cockroach pollination and compare the effectiveness...

Ecological network theory hypothesizes that the structuring of species interactions can convey stability to the system. Investigating how these structures react to species loss is fundamental for understanding network disassembly or their robustness. However, this topic has mainly been studied in‐silico so far. Here, in an experimental manipulation...

In recent years the herpetological trade has become increasingly accessible to pet owners. What was once a specialist hobby between a network of keepers has now become mainstream, with reptiles and amphibians often found in general pet shops and online. Animal welfare legalisation has struggled to keep up with this rapid growth, and we have little...

For more than a century there has been a fascination with the surprisingly rapid rise and early diversity of flowering plants (angiosperms). Darwin described the seemingly explosive diversification of angiosperms as an “abominable mystery,” and debates continue about the origin and processes driving angiosperm speciation. Dating the origin of angio...

Ecological network theory hypothesizes a link between structure and stability, but this has mainly been investigated in-silico. In an experimental manipulation, we sequentially removed four generalist plants from real plant-pollinator networks and explored the effects on, and drivers of, species and interaction extinctions, network structure and in...

Insect pollinators face a number of well-documented threats that challenge their survival at an individual and community level. The effect of extreme events on pollinator assemblages has received little attention to date, partly due to a lack of consensus on what constitutes extreme, but also because robust pre-event data is often lacking. Here, th...

Societal Impact Statement Plant–pollinator relationships are fundamentally important for the conservation of the terrestrial biodiversity that rural communities in low‐income countries rely upon. In Nepal, a country that is biologically rich but economically poor, Rhododendron forests provide a range of ecosystem services that are under threat from...

Species extinctions undermine ecosystem functioning, with the loss of a small subset of functionally important species having a disproportionate impact. However, little is known about the effects of species loss on plant-pollinator interactions. We addressed this issue in a field experiment by removing the plant species with the highest visitation...

Background and Aims Large clades of angiosperms are often characterized by diverse interactions with pol-linators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of speci...