THE EFFECTS OF ENVIRONMENTAL FLUCTUATIONS ON RUNNING WATER ECOSYSTEMS Guy Woodward and Samraat Pawar have just published a multi- authored paper in Philosophical Transactions of the Royal Society B on effects of climatic fluctuations and extreme events (droughts, floods, heatwaves, cold spells) on ecosystems in riverine landscapes — i.e., the river network, the floodplain and the flow catchment. Most climate change research in freshwaters has been focused on the more gradual effects of a warming trend, rather than the severe spikes and troughs in temperature and water availability that are widely predicted to accompany it, and which may be far more important in shaping ecological responses. Our understanding of the impacts of environmental fluctuations on this very important class of ecosystems, upon which a significant proportion of the human population depends across the world, is therefore currently very limited. Above: Grey heron. Photo: Guy Woodward The authors develop a new theoretical and conceptual framework for better predicting impacts of environmental change on these ecosystems, by studying the effects first at the level of individuals and then “scaling” them up through pair-wise species interactions in local food webs, to multiple dynamically changing food webs connected by species exchanges between them. They also review current empirical data on the impacts of environmental change on riverine ecosystems, and identify key areas for future empirical and theoretical work. Philosophical Transactions of the Royal Society B 371:20150274 (2016). Prof. Guy Woodward and Dr Samraat Pawar Contact: [email protected]; [email protected]PROTECTING AN ECOSYSTEM SERVICE: APPROACHES TO UNDERSTANDING AND MITIGATING THREATS TO WILD INSECT POLLINATORS Insect pollination constitutes an ecosystem service of global importance, providing significant economic and aesthetic benefits as well as cultural value to human society, alongside vital ecological processes in terrestrial ecosystems. It is therefore important to understand how insect pollinator populations and communities respond to rapidly changing environments if we are to maintain healthy and effective pollinator services. Dr Richard Gill was awarded NERC and BBSRC funding to hold a 2-day workshop meeting to bring together leading academics, Continued on page 3 Silwood Park News SCIENCE FOR THE LIVING PLANET June 2016, Volume 1, Issue 2 Department of Life Sciences, Faculty of Natural Sciences FISH DIVERSITY RECEIVES A BOOST WHEN SPECIES EVOLVE LIVE BIRTHS Most fish lay eggs, but some species have evolved the ability to give birth to live young, a strategy known as viviparity. By analysing the family tree of the Cyprinodontiformes group of fish, which includes many aquarium species such as guppies, mollies and killifish, PhD student Andrew Helmstetter discovered that the evolution of viviparity led to a rash of new species. Above: Two males belonging to the annual killifish genus Nothobranchius. In the wild these fish are found in seasonal pools across Africa. Photo: Andrew Bogott. The research team, led by Professor Vincent Savolainen from Imperial, believe viviparity is beneficial because it allows pregnant fish to travel with their young and find new areas to colonise. Once settled in a new area, away from others of the same species, these fish pioneers can become separate species of their own. The team were surprised to find that a second birth strategy they investigated did not fare so well. Some fish in the same group have evolved a strategy known as annualism – an annual life cycle. Some species of killifish have evolved to take advantage of seasonal ponds, laying their eggs in the wet season. When the ponds dry out, the eggs remain dormant until the rains return and they hatch. The researchers thought this would lead to many new species as it allows killifish to find new areas to colonise that are separated from other fish of the same species. However, the evolution of annualism was not followed by a surge in diversification as expected. This is the first large study of reproductive strategies and diversity in fish. Nature Communications 7:11271 (2016). Prof. Vincent Savolainen Contact: [email protected]ALSO IN THIS ISSUE: - A message from the Deputy Head of Department - New Grants - Long term ecological experiments - Imperial Festival 2016 - CT scanning bee brains 1 SILWOOD PARK NEWS VOLUME 1: ISSUE 2 JUNE 2016 www.imperial.ac.uk/visit/campuses/silwood-park/
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THE EFFECTS OF ENVIRONMENTAL FLUCTUATIONS ON RUNNING WATER ECOSYSTEMS
Guy Woodward and Samraat Pawar have just published a multi-authored paper in Philosophical Transactions of the Royal Society B on effects of climatic fluctuations and extreme events (droughts, floods, heatwaves, cold spells) on ecosystems in riverine landscapes — i.e., the river network, the floodplain and the flow catchment.
Most climate change research in freshwaters has been focused on the more gradual effects of a warming trend, rather than the severe spikes and troughs in temperature and water availability that are widely predicted to accompany it, and which may be far more important in shaping ecological responses.
Our understanding of the impacts of environmental fluctuations on this very important class of ecosystems, upon which a significant proportion of the human population depends across the world, is therefore currently very limited.
Above: Grey heron. Photo: Guy Woodward
The authors develop a new theoretical and conceptual framework for better predicting impacts of environmental change on these ecosystems, by studying the effects first at the level of individuals and then “scaling” them up through pair-wise species interactions in local food webs, to multiple dynamically changing food webs connected by species exchanges between them. They also review current empirical data on the impacts of environmental change on riverine ecosystems, and identify key areas for future empirical and theoretical work. Philosophical Transactions of the Royal Society B 371:20150274 (2016).
PROTECTING AN ECOSYSTEM SERVICE: APPROACHES TO UNDERSTANDING AND MITIGATING THREATS TO WILD INSECT POLLINATORS
Insect pollination constitutes an ecosystem service of global importance, providing significant economic and aesthetic benefits as well as cultural value to human society, alongside vital ecological processes in terrestrial ecosystems. It is therefore important to understand how insect pollinator populations and communities respond to rapidly changing environments if we are to maintain healthy and effective pollinator services.
Dr Richard Gill was awarded NERC and BBSRC funding to hold a 2-day workshop meeting to bring together leading academics,
Continued on page 3
Si lwood Park NewsSCIENCE FOR THE L IV ING PLANET
June 2016, Volume 1, Issue 2Department of L i fe Sc iences, Facul ty of Natura l Sc iences
FISH DIVERSITY RECEIVES A BOOST WHEN SPECIES EVOLVE LIVE BIRTHS
Most fish lay eggs, but some species have evolved the ability to give birth to live young, a strategy known as viviparity. By analysing the family tree of the Cyprinodontiformes group of fish, which includes many aquarium species such as guppies, mollies and killifish, PhD student Andrew Helmstetter discovered that the evolution of viviparity led to a rash of new species.
Above: Two males belonging to the annual killifish genus Nothobranchius. In the wild these fish are found in seasonal pools across Africa. Photo: Andrew Bogott.
The research team, led by Professor Vincent Savolainen from Imperial, believe viviparity is beneficial because it allows pregnant fish to travel with their young and find new areas to colonise. Once settled in a new area, away from others of the same species, these fish pioneers can become separate species of their own.
The team were surprised to find that a second birth strategy they investigated did not fare so well. Some fish in the same group have evolved a strategy known as annualism – an annual life cycle. Some species of killifish have evolved to take advantage of seasonal ponds, laying their eggs in the wet season. When the ponds dry out, the eggs remain dormant until the rains return and they hatch.
The researchers thought this would lead to many new species as it allows killifish to find new areas to colonise that are separated from other fish of the same species. However, the evolution of annualism was not followed by a surge in diversification as expected. This is the first large study of reproductive strategies and diversity in fish. Nature Communications 7:11271 (2016).
1 SILWOOD PARK NEWS VOLUME 1: ISSUE 2 JUNE 2016 www.imperial.ac.uk/visit/campuses/silwood-park/
SILWOOD PARK LONG-TERM STUDIES
Long-term studies have been central to understanding fundamental ecological processes that influence the structure and dynamic of natural and agricultural ecosystems. They are also a powerful tool to assess the effects of the environmental changes produced by human activities and to help find solutions to mitigate their impact on the ecosystem and society.
Silwood Park hosts eleven active long-term field studies, some of which have been run for decades. They are helping to test a broad range of hypotheses that explain the impact of agrochemicals and alteration of grazers-plant interactions in plant and microbial communities, the effect of climate change on the assembly of natural communities and ecosystem function, and the effect of complex species interactions and habitat structure in population dynamics and animal behaviour.
The long-term experiments working group at Silwood Park has created a data repository to safeguard ecological data collected in the grounds of Silwood Park for its preservation and use in research and teaching. A website now linked to Silwood Research also explains the questions that motivated the creation of each study, describing in detail their experimental design and data available, and listing the publications they have produced.
The Long-term experiment pages also contain maps and pictures to help identify the studies on the ground. We anticipate that this initiative will stimulate the use of the experiments and the invaluable data they have produced to ask new questions and motivate new research collaborations. We also expect that this will help highlight the value and potential of the experimental research at Silwood Park contributing to obtain support for the long-term preservation of field studies. http://www.imperial.ac.uk/visit/campuses/silwood-park/research/
Below: a nest box from the long-term study of blue tits breeding ecology, Mann’s Copse, Silwood Park. Photo: Catalina Estrada.
A MESSAGE FROM THE DEPUTY HEAD OF LIFE SCIENCES (SILWOOD PARK)
As I step down from Deputy Head of Department (DHoD) for Silwood Park, it is time to reflect on a busy four years.
We have seen a 34% increase in the number of academic staff, including 18 new appointments and increased number of female academics. We have re-organised the support staff and welcome here Dr Catalina Estrada, our ecological analyst and facility manager, and Dr Alba Yebes, the new genomic analyst and laboratory manager. Research volume and numbers of masters students have both increased by a third. We have seen significant investments in our research infrastructure, including over £1.8M to develop a microbial ecology suite, Hamilton laboratories, and the newly open Wolfson ecological genomics facility; further funding has been secured for a new building with controlled environment chambers, and possibly outdoor aviaries.
Finally, campus facilities are improving too, from a nursing mother’s room and baby changing facility and a new catering company to the refectory and bar. Of course, there are always challenges ahead, in particular with continuing to improve facilities, quality and levels of delivery for our postgraduate programmes.
As we welcome our new DHoD, Professor Tim Barraclough, I look forward to these exciting developments and thank everybody for their help and hard work; Silwood is in a strong position for its future.
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Above: A photo from the Silwood Park archives taken in May 1959.
If you would like to contribute to the next issue of Silwood Park News, Science for the Living Planet, or if you have any comments about this issue, please contact Victoria Ireton at [email protected]
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(Continued from page 1)industry, practitioners, stakeholders and charities to discuss these issues and provide consultation to the National Pollinator Strategy of England as to where the evidence gaps are.
As a result Dr Gill led the publication of a paper that considered the importance of conserving pollinator diversity to maintain a suite of functional traits and provide a diverse set of pollinator services. They explored how we can better understand and mitigate the factors that threaten insect pollinator richness, placing our discussion within the context of populations in predominantly agricultural landscapes in addition to urban environments. Advances in Ecological Research 54:135 (2016).
Below: Set of environmental stressors which can threaten pollinator communities. Persistently induced stress may lead to pollinator population declines resulting in the composition and stability of pollinator communities to be affected with potential loss of species richness and reduced pollination insurance. Loss of pollinator services
NEW GRANT: ADDITIONAL FUNDING FOR PROJECT ADDRESSING THE NEED FOR INNOVATIVE TOOLS FOR VECTOR CONTROL OF MALARIA
In March this year Austin Burt, Professor of Evolutionary Genetics, at Silwood Park secured a further 3.5 year extension ($34m) to his 2005 initial concept of developing a technology to reduce the population of malaria-transmitting mosquitoes in sub-Saharan Africa and therefore reducing the transmission of the disease. Now known as Target Malaria, the project is an innovative not-for-profit research consortium that since its inception has grown to support over 100 FTE’s, with 4 teams at Imperial and a further 13 different institutes in the US, Europe and Africa, including scientists, stakeholder engagement teams, risk assessment specialists and regulatory experts.
The project’s focus is on reducing the number of female malaria mosquitoes. Only female mosquitoes bite and the number of productive females in a population will usually determine future population size. As a mechanism to reduce the number of female Anopheles gambiae mosquitoes, the teams are investigating the use of genes that produce enzymes (called nucleases) that cut specific sequences of DNA. The concept for these nucleases is based on Homing Endonuclease Genes (HEGs) which are a class of nuclease genes, found in simple single celled organisms, which are capable of copying themselves from one chromosome to another. In principle there are several types of endonuclease that can be re-programmed to act in a similar way to HEGs and we are testing a wide range of these nucleases.
The ultimate goal of all of the strategies is to produce modified malaria mosquitoes that can pass these genes on to a disproportionately
high percentage of their offspring, so the modification is spread throughout the specific population relatively quickly and is effectively “self-sustaining”. This makes the reduction of the malaria mosquito vector population relatively cost effective and simple to implement because the mosquitoes themselves do the work. Two of the main areas we are currently focussing on are biasing the sex ratio of mosquito populations and reducing female fertility.
Target Malaria is funded by a program of the Bill & Melinda Gates Foundation
For more information about our work please visit our website www.targetmalaria.org
Above: Just some of the 100 strong Target Malaria team. Photo: Axel Fassio, Fassio Photography.
NEW GRANT: BIODIVERSITY AND ECOLOGICAL RESEARCH IN BRAZIL
As in other parts of the world with similar soils and climate, the natural vegetation of the Northeast Brazil is a form of deciduous scrub, known locally as Caatinga. Probably because these dry shrublands typically lack the complexity and grandeur of moist tropical forests, this vegetation type has to large extent neglected to date, both in terms of conservation programmes and scientific enquiry.
To address this neglect, the UK Natural Environmental Research Council (NERC) and the São Paulo Research Foundation FAPESP: Fundação de Amparo à Pesquisa do Estado de São Paulo have jointly funded a ca. £2M integrated research program involving both Brazilian and UK researchers. On the UK side this three-year project is to be led by the Silwood Park based Professor Colin Prentice of Imperial College, with the overall objective of developing a functional understanding of biome-wide variations in species distributions, ecosystems fluxes and the development of a long-term conservation plan for this long-neglected biome which interestingly, as well as small trees, shrubs and scattered grasses and herbs also contains less common succulent-type life-forms such as bromeliads and cacti often all growing in the one place.
Above: Semi-arid “sertão” caatinga located near Arcoverde, Pernambuco State, Brazil. Photo: Jon Lloyd.
Other UK partners include University of Reading, University of Leeds and Royal Botanic Gardens Edinburgh. Within Brazil the lead partner institution will be Universidade de São Paulo at Ribeirão Preto, where Professor Jon Lloyd, also of Silwood Park, is to hold an associated “São Paulo Excellence Research Chair” for the duration of the project.
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EXPLORING MINIATURE INSECT BRAINS USING MICRO-CT SCANNING TECHNIQUES
Detailed images of bumblebee brains reveal an accurate picture of brain structures associated with learning and memory. Bumblebee brains have been visualised in unprecedented detail using new techniques in micro-CT imaging, allowing researchers to accurately measure tiny brain structures linked to surprisingly complex memory and learning abilities. Whilst bumblebees have relatively simple brains compared to our own human brain, they are able to perform complex learning tasks, such as remembering the best places to forage for nectar and pollen.
Dr Richard Gill says: “it’s a fantastic way to look inside insect brains. We can look at the brain as it naturally sits in the bee’s head, without the human error of having to extract it.” Given their importance as pollinators for crops and wild flowers, understanding how damage to bees’ brains affects their behaviour can help researchers understand what causes bee brains to malfunction. Until now, scientists studying insect brains had to remove them and slice them up, causing damage to the structures and preventing accurate measurement of their size and shape. However the new study uses non-destructive techniques by applying micro-CT. “The 3D structures can also be explored as you wish – from looking at the whole organ down to each separate structure, piece by piece.”
Above: Image of part of a bumblebee head case created by PhD student Dylan Smith with the image scans produced on a micro CT scanner at the NHM and led by Farah Ahmed.
Dylan Smith, the lead author also from the Department of Life Sciences at Imperial said: “With older techniques, the sizes of these structures could not be accurately measured and compared between bees. The structures are so small that tiny errors in measurement can lead to wrong conclusions. This new technique allows structures to be isolated, examined, and measured in greater detail than ever before.” The team also hope to be able to use the technique to study the effects of trauma on the brains of bees and whether certain influences affect the memory and learning centres, affecting their ability to forage and pollinate effectively.
FUNCTIONAL TRAITS AND THE STRUCTURE OF BIODIVERSITY GRADIENTS
A famous series of studies by Robert MacArthur clarified that variation in species richness across environmental gradients may be associated with an expanded volume or increased packing of ecological niche space. However, the relative importance of these alternative scenarios remains unknown, largely because standardized information on functional traits and their ecological relevance is lacking for major diversity gradients.
Continued on p.5
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Continued from p.3Professor Vincent Savolainen, coI, will contribute to a genetic component of the research. Also involved from Imperial College will be Dr Tania Stathaki (Dept. of Electrical Engineering) who will be working on applying new image analysis techniques for ecosystem canopy cover quantification.
ECOLOGICAL AND METHODOLOGICAL DRIVERS OF SPECIES’ DISTRIBUTION AND PHENOLOGY RESPONSES TO CLIMATE CHANGE
Climate change is shifting species’ distribution and phenology. Ecological traits, such as mobility or reproductive mode, explain variation in observed rates of shift for some taxa. However, estimates of relationships between traitsand climate responses could be influenced by how responses are measured.
We compiled a global data set of 651 published marine species’ responses to climate change, from 47 papers on distribution shifts and 32 papers on phenology change. We assessed the relative importance of two classes of predictors of the rate of change, ecological traits of the responding taxa and methodological approaches for quantifying biological responses. Methodological differences explained 22% of the variation in range shifts, more than the 7.8% of the variation explained by ecological traits. For phenology change, methodological approaches accounted for 4% of the variation in measurements, whereas 8% of the variation was explained by ecological traits. Our ability to predict responses from traits was hindered by poor representation of species from the tropics, where temperature isotherms are moving most rapidly.
Thus, the mean rate of distribution change may be underestimated by this and other global syntheses. of Our analyses indicate that methodological approaches should be explicitly considered when designing, analysing and comparing results among studies. To improve climate impact studies, we recommend that (1) reanalyses of existing time series state how the existing data sets may limit the inferences about possible climate responses; (2) qualitative comparisons of species’ responses across different studies be limited to studies with similar methodological approaches; (3) meta-analyses of climate responses include methodological attributes as covariates; and (4) that new time series be designed to include the detection of early warnings of change or ecologically relevant change. Greater consideration of methodological attributes will improve the accuracy of analyses that seek to quantify the role of climate change in species’ distribution and phenology changes. Global Change Biology 22: 1548 (2016).
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These palms are associated with distinct soil types and have displaced flowering times, representing an ideal candidate for ecological speciation. The researchers generated large amounts of RNA-Seq data from multiple individuals and tissue types collected on the island from each of the two species. They found that differentially expressed loci as well as those with divergent coding sequences between Howea species were associated with known ecological and phenotypic differences, including response to salinity, drought, pH and flowering time. They identified loci with potential dual function in flowering time and soil adaptation, which effect on flowering time was validated by knocking orthologous genes in a model plant species. TThese results indicate that pleiotropy could have favoured the evolution of barrier traits in this system, despite ongoing gene flow. J. Evol. Biol. in press.
SIMILAR BIODIVERSITY OF ECTOMYCORRHIZAL FUNGI IN SET-ASIDE PLANTATIONS AND ANCIENT OLD-GROWTH BROADLEAVED FORESTS
Above: Mycorrhizas of oak with the candy cap mushroom. Photo: Laura Suz.
In parts of the world that have experienced a vast loss of forests, like Britain, where little forest area remains and only 5% of it is ancient, setting-aside plantations of trees offers an opportunity to increase areas that can support the diversity and ecosystem functions that characterize ancient forests. However, this possibility had not been tested. In collaboration with researchers from the University of Southampton, Bournemouth University and the Royal Botanic Gardens, we investigated the value of economically over-mature forests ca. 180 years old vs. stands more than 1,000 years old for root-symbiotic fungi (mycorrhizas) and their mushrooms, a key functional group, in the New Forest. We found that set-aside is an effective option for keeping diversity, particularly for mixed woods with large basal area. Biological Conservation 194:71 (2016).
UNDERSTANDING THE LINK BETWEEN ENERGY AND BIODIVERSITY
The association between species richness and ecosystem energy availability is one of the major geographic trends in biodiversity. It is often explained in terms of energetic con- straints, in line with the idea that coexistence among competing species is limited in low productivity environments. However, it has proven challenging to reject alternative views, including the null hypothesis that species richness has simply had more time to accumulate in productive regions.
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What are the mechanisms linking ecosystem productivity with vertebrate diversity? Evidence from birds suggests that this general relationship can be explained by faster transitions into coexistence, and slower transitions away from coexistence, in closely related species living in high productivity environments. Photo: Joe Tobias.
A team of researchers led by Joseph Tobias (Imperial College London) addressed this issue by combining data on morphological and ecological traits for 523 species of passerine birds distributed across an Andes-to-Amazon elevation gradient. They showed that morphological traits capture substantial variation in species dietary (75%) and foraging niches (60%) when multiple independent trait dimensions are considered. Having established these relationships, they showed that a 14-fold increase in species richness towards the lowlands is associated with both an increased volume and density of functional trait space. A key finding was that increases in volume contribute little to changes in richness, with most (78%) lowland species occurring within the range of trait space occupied at high elevations.
The results suggest that high species richness is mainly associated with a denser occupation of functional trait space, implying an increased specialization or overlap of ecological niches, and supporting the view that niche packing is the dominant trend underlying gradients of increasing biodiversity towards the lowland tropics. Proceedings of the Royal Society B 283:1822 (2015).
Professor Vincent Savolainen has led speciation research on Lord Howe Island for over a decade. In this paper, Savolainen and his team report on ‘speciation genes’ underlying a case of sympatric speciation in island palms.
Below: Lord Howe Island, a natural laboratory for speciation research. Photo: Vincent Savolainen.
Ecological speciation requires divergent selection, reproductive isolation, and a genetic mechanism to link the two. Savolainen examined the role of gene expression and coding sequence evolution in this process using two species of Howea palms that have diverged sympatrically on Lord Howe Island, Australia.
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A recent Silwood publication shed light on this by building a model of speciation and extinction that explicitly incorporates long-term geological processes including the movement of the continents. The work was conducted by masters student Sean Jordan (who studied on the Computational Methods in Ecology and Evolution course) and his supervisors Tim Barraclough and James Rosindell.
The results showed that continental drift alone was unlikely to provide a sufficient explanation for the increase in species diversity, but it may explain the increase in diversity for higher taxa such as families or orders. Philos Trans R Soc Lond B Biol Sci 371 (2016).
SEX DIFFERENCES IN RELATIONSHIPS BETWEEN HABITAT USE AND REPRODUCTIVE PERFORMANCE IN SOAY SHEEP (OVIS ARIES)
It is unusual to know the lifetime reproductive success of a long-lived, free-living animal. It is even more unusual to know this for long-lived, free-living males, because of the difficulty of assigning paternity under field conditions.
The Soay Sheep on St Kilda are one of the few study-systems where such data are available for many hundreds of animals of both sexes over several decades. In addition, the location of every animal is mapped with 100m-resolution on at least 30 occasions each year throughout its life. What makes the St Kilda study system unique is that the flora is also mapped at a resolution of 100m, so every single hectare of the 650ha study-area has a unique set of cover values for every vascular plant species growing in it.
This means that the lifetime reproductive success of each individual animal can be related to the weighted average botanical composition of its home range. This has never been done before. Theory (in the form of the ideal free distribution) predicts that fitness should not vary with spatial location because of the trade-off between habitat quality and intraspecific competition: animals should only leave a higher quality patch when the costs of competition outweigh the benefits of staying. Soay Sheep have not understood this theory properly.
What Charlotte Reagan has discovered is that females from home ranges with higher food quality (which in this case means more Holcus and less Calluna) show higher lifetime reproductive success. In contrast males, who get their reproductive success by chasing down oestrus females over long distances, showed no such relationship between food quality in the home range and lifetime reproductive success.
It is worth noting that different females have rather similar lifetime reproductive successes (between 4 and 8 surviving lambs), but males show massive skew, with most individuals fathering no offspring at all, and others fathering as many as 100 offspring. This is the first study to document small-scale spatial heterogeneity in lifetime fitness measured under field conditions. Ecology Letters 19: 171 (2016).
Below: The remote island of St Kilda is ideal for the study of animals’ population dynamics as there is no possibility of immigration or emigration. The animals distribute themselves across the heterogeneous plant communities in a pattern that does not conform to the ideal free distribution.
A team led by researchers from Imperial College London (Joseph Tobias and Walter Jetz) tackled this question using the phylogenetic relationships and geographic ranges of sister species (pairs of lineages who are each other’s closest extant relatives) to examine the association between energy availability and coexistence across an entire vertebrate class (birds). They showed that the incidence of coexistence among sister species increases with overall species richness and is elevated in more productive ecosystems, even when accounting for differences in the evolutionary time available for coexistence to occur. The results indicate that energy availability promotes species coexistence in closely related lineages, providing a key step toward a more mechanistic understanding of the productivity–richness relationship underlying global gradients in biodiversity.
Below: The 14-fold build-up of species richness across the Andes-Amazon elevational gradient is unevenly distributed across dietary groups, and largely driven by an increase in specialist insectivores
Image: Pigot et al., 2016.
QUANTIFYING THE EFFECTS OF THE BREAK UP OF PANGAEA ON GLOBAL TERRESTRIAL DIVERSIFICATION WITH NEUTRAL THEORY
Aggregated global fossil data appears to show that the number of different species on earth has increased substantially over the last 200 million years. Several possible explanations for this have been suggested. It could be that older fossils are harder to find because they’ve had more time to decay, or that conditions on earth have not always been so suitable for producing fossils as they have been in recent geological time. The more interesting explanation, however, is that the evolutionary ‘speciation’ processes that produce species have sped up, which may be due to the splitting and movement of the continents providing more opportunities for species to form.
Above: The approximate land mass positions at (a) 180, (b) 165, (c) 135, (d) 132, (e) 80, (f) 55, (g) 33 and (h) 12 Million years ago. The graph shows Tetrapod (combined mammal, bird, amphibian and reptile) diversity and change in global average temperature. Image from Jordan et. al. Phil. Trans. R. Soc. B 371: 20150221.
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WELCOME TO OUR NEW STAFF
Dr Catalina Estrada, Dr Estrada has joined us as ecologist analyst and facilities manager. She is responsible for supporting research groups spanning areas ranging from malaria control, working with saving the world’s bees, experiments in our pond mesocosm facility, working with wild and captive birds, and long-term field experiments on the Silwood grounds.
Dr Alba Herraiz Yebes
Dr Herraiz Yebes will join us in September as Genomic Analyst and Laboratory Manager. She will be responsible for research support in genomics, including data management and archiving, development and implementation of standard workflows and bioinformatics pipelines, analysis of high throughput genomic data, and managing the Wolfson Laboratory for Ecological Genomics and associated laboratories.
Dr Morena Mills
Dr Mills will join us in the Autumn as Senior Lecturer in conservation science. She is interested in human-environmental issues, in particular, issues related to the drivers, impacts and sustainability of grassroots, co-managed and top-down conservation initiatives. Much of her research to date has been on how systematic conservation planning can better inform day-to-day resource management decisions.
Dr Matteo Fumagalli
Dr Fumagalli will join us shortly as a Human Frontier Science Program fellow. His research has focuses on developing computational methods to look for signatures of natural selection in genomes and to infer population demographic histories. He analyses large-scale genomic datasets of model and non-model species.
IMMIGRATION IMPAIRS ADAPTATION OF WARMED MICROBIAL COMMUNITIES
Microbial communities are hugely diverse and we still have little understanding of the ecological and evolutionary processes operating in these complex systems in nature. We used field experiments in the Silwood grounds to look at how bacteria communities respond to changing environments - namely temperature. Theory predicts that immigration can either enhance or impair the rate at which species and whole communities adapt to environmental change. We therefore compared responses in microcosms that were either open or closed to immigration of new species. The effects of immigration depended on the warming treatment. In warmed communities, immigration was detrimental to community growth, whereas in ambient communities it was beneficial. This result is explained by colonists coming from a local species pool preadapted to ambient conditions. Loss of metabolic diversity, however, was buffered by immigration in both environments. Communities became ‘locally adapted’ to the experimental conditions over time. This was not because each species was locally adapted but because of changes in species interactions over time. Tracking processes in wild bacterial communities is challenging - our ongoing work tackles this challenge by combining experiments in Silwood’s grounds, mathematical models and high-throughput genomic and metabolomic methods. American Naturalist 87:236 (2016).
Samraat Pawar and Dan Goodman (Department of Electrical and Electronic Engineering) had an exhibition stand at the recently concluded Imperial Festival on the theme of Ecosystem Control and Engineering. The stand’s main attraction was a video game (www.ecobuildergame.org) being developed through a collaboration between the Pawar and Goodman Labs, and live exhibits of trophic interactions contributed by Chris Wilson, and the Woodward, and Bell labs. The stand was a big hit, with over 500 adults and children visitors, most of whom had a go at either watching real predation, building ecosystems though the video game, or both! The group now plan to trial the game as an educational tool in some local schools. The game continues to be developed as an educational and research tool.
Above: Visitors to the Imperial Festival 2016 try out the Ecobuilder video game developed by Dr Pawar and Dr Goodman ‘s labs. Photo: Samraat Pawar.
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MSc and MRes Programmes at Silwood Park
Research
Silwood Park Campus is home to the Department of Life Sciences Evolutionary Biology Theme, the Ecosystems & the Environment Theme and Grand Challenges in Ecosystems & the Environment Initiative.
The Grand Challenges in Ecosystems and the Environment Initia-tive was launched in 2013. Working across scales and combining theory, observation and manipulative experimentation the Grand Challenges Initiative aims to develop fundamental science and design innovative solutions to tackle some of the greatest environmental challenges facing the world.
Other groups active at the Silwood Park Campus include the Centre for Environmental Policy, the Imperial College Reactor Centre and the International Pesticide Application Research Centre.
MSc Conservation ScienceA rapidly growing area of interdisciplinary research, which informs policy decisions regrading the management of the biodiversity and ecosystem services upon which humans depend
MSc and MRes Computational Methods in Ecology and EvolutionIn this unique course, we teach computational methods and biological concepts together, through application of the methods to cutting-edge biological research applications
MSc and MRes Ecology, Evolution and ConservationBroad research training in ecology, evolution and conservation, suitable for a career in applied biology, conservation or as preparation for a PhD
MSc Ecological ApplicationsThis full-time, one-year course provides broad training in the applications of ecological and evolutionary theory and skills to real world problems
MRes Ecosystem and Environmental ChangeA cutting-edge interdisciplinary programme, providing high-level research training in the latest developments in the conservation of ecosystems and the environment
MRes in Tropical Forest EcologyThis course provides students with high-level research training in the latest developments in tropical forest ecology
MSc Taxonomy and BiodiversityRun jointly by Imperial College London and the Natural History Museum in South Kensington, a leading institute in systematics research, where the students will be based.
