The study of interactions and their impacts on communities is a fundamental part of ecology. Much work has been done on measuring the interactions between species and their impacts on relative abundances of species. Progress has been made in understanding of the interactions at the ecological level, but we know that co-evolution is important in shaping the structure of communities in terms of the species that live there and their characteristics. Continue reading
Interactions between plants and pollinators tend to be highly generalized.
In 1980, Janzen published an article titled “When is it coevolution?” where he explained the concept of diffuse coevolution: the idea that evolution of interacting species is shaped by entire communities, rather than simple paired interactions. This idea, though compelling, remains poorly understood, and strong evidence of diffuse coevolution acting on a community is lacking. Perhaps this is because there’s a lack of consensus on what would constitute evidence in support of the concept of diffuse coevolution, or, indeed, coevolution in general (Nuismer et al 2010). Continue reading
©Luísa G. Carvalheiro
Ecological networks represent interactions between different biotic units in an ecosystem and are becoming an increasingly popular tool for describing and illustrating a range of different types of ecological interactions. Food webs – which provide a way to track and quantify the flow of energy and resources in ecosystems – are among the most studied type of ecological networks. These networks usually represent species (nodes) which are connected by pairwise interactions (links) and they play a central role in improving our understanding of ecological and evolutionary dynamics.
Historically, food webs described antagonistic relationships (e.g. plant-herbivore or host-parasitoid networks) but the approach has been developed in recent years to include mutualistic networks (e.g. plant-pollinator networks, phorophyte-epiphyte networks). The development of network ecology, including ever more sophisticated methods to analyse ecological communities, has been driven forward by an enthusiastic community of ecologists, theoreticians and modellers working together to enhance our understanding of how communities interact.
In this blog post, we’ll describe the important role played by female scientists in the development of network ecology, focusing on the contributions by two ground-breaking ecologists and also highlighting contributions from a range of other scientists working in this field. Continue reading
Image from the Canon PowerShot camera with CHDK script ‘Motion Detect Plus’. The thistle flower being visited by ♀ honeybee Apis mellifera L.
Pollinators have fascinated ecologists for decades, and they have traditionally been monitored by on-site human observations. This can be a time-consuming enterprise and – more importantly – species identification and recordings of behaviour have to be registered at the time of observation. This has two complications:
Although on-site human observations have predominated, today’s widespread availability of digital monitoring equipment has enabled unique data on flower visitors to be collected. In my research, I have used a time-efficient automated procedure for monitoring flower-visiting animals – namely foraging bumblebees visiting focal white clovers and honeybees visiting thistles.
To understand how species survive in nature, demographers pair field-collected life history data on survival, growth and reproduction with statistical inference. Demographic approaches have significantly contributed to our understanding of population biology, invasive species dynamics, community ecology, evolutionary biology and much more.
As ecologists begin to ask questions about demography at broader spatial and temporal scales and collect data at higher resolutions, demographic analyses and new statistical methods are likely to shed even more light on important ecological mechanisms.
Midsummer Opuntia cactus in eastern Idaho, USA. © B. Teller.
Traditionally, demographers collect life history data on species in the field under one or more environmental conditions. This approach has significantly improved our understanding of basic biological processes. For example, rosette size is a significant predictor of survival for plants like wild teasel (Werner 1975 – links to all articles are at the end of the post), and desert annual plants hedge their bets against poor years by optimizing germination strategies (Gremer & Venable 2014).
Demographers also include temporal and spatial variability in their models to help make realistic predictions of population dynamics. We now know that temporal variability in carrying capacity dramatically improves population growth rates for perennial grasses and provides a better fit to data than models with varying growth rates because of this (Fowler & Pease 2010). Moreover, spatial heterogeneity and environmental stochasticity have similar consequences for plant populations (Crone 2016). Continue reading
Nick and Charlie are giving a presentation on ‘Biodiversity Indicators from Occurrence Records’ at the BES Annual Meeting on Wednesday 16 December at 13:30 in Moorfoot Hall. Charlie will also be presenting a poster on Tuesday 15 December between 17:00 and 18:30 on ‘Monitoring the UK’s less well-studied species using biological records‘ in the Lennox Suite.
Biodiversity Indicators are some of the most important tools linking ecological data with government policy. Indicators need to summarise large amounts of information in a format that is accessible to politicians and the general public. The primary use of indicators is to monitor progress towards environmental targets. For the UK, a suite of indicators are produced annually which are used to monitor progress towards the Aichi targets of the Convention on Biological Diversity as well as for European Union based commitments. However, this is complicated by the fact that biodiversity policy within the UK is devolved to each of the four nations, so additional indicators have been developed to monitor the commitments of each country.
© Dave Colliers
A range of biodiversity indicators exist within this suite covering the five strategic goals of the Convention; which include addressing the causes of biodiversity loss, reducing pressures on biodiversity and improving status of biodiversity within the UK. Within strategic goal C (improve status of biodiversity by safeguarding ecosystems, species and genetic diversity) there are currently 11 “State” indicators that use species data to monitor progress towards the targets underlying this goal. Most existing species based indicators use abundance data from large scale monitoring schemes with systematic protocols. However, there are other sources of data, such as occurrence records, that can offer an alternative if they are analysed using the appropriate methods. This post will discuss the development of species indicators for occurrence records to complement the current UK species based indicators, specifically relating to the C4b priority species indicator and the D1c pollinators indicator. Continue reading
Below is a press release about the Open Access Methods paper ‘Image calibration and analysis toolbox – a free software suite for objectively measuring reflectance, colour and pattern‘ taken from the University of Exeter:
New camera technology that reveals the world through the eyes of animals has been developed by University of Exeter researchers. The details are published today in the journal Methods in Ecology and Evolution.
Echium angustifolium in Tenerife (Borage family). To us the flowers are a fairly uniform purple, but bees can see two UV absorbent patches at the top of the flower.
The software, which converts digital photos to animal vision, can be used to analyse colours and patterns and is particularly useful for the study of animal and plant signalling, camouflage and animal predation, but could also prove useful for anyone wanting to measure colours accurately and objectively.
The software has already been used by the Sensory Ecology group in a wide range of studies, such as colour change in green shore crabs, tracking human female face colour changes through the ovulation cycle, and determining the aspects of camouflage that protect nightjar clutches from being spotted by potential predators. Continue reading
Below is a press release about the Methods paper ‘High-throughput monitoring of wild bee diversity and abundance via mitogenomics‘ taken from the University of East Anglia:
It may sound counter-intuitive, but crushing up bees into a ‘DNA soup’ could help conservationists understand and even reverse their decline – according to University of East Anglia scientists.
Research published today in the journal Methods in Ecology and Evolution shows that collecting wild bees, extracting their DNA, and directly reading the DNA of the resultant ‘soup’ could finally make large-scale bee monitoring programmes feasible.
©Mibby23 (click image to see original version)
This would allow conservationists to detect where and when bee species are being lost, and importantly, whether conservation interventions are working.
The UK’s National Pollinator Strategy outlines plans for a large-scale bee monitoring programme. Traditional monitoring involves pinning individual bees and identifying them under a microscope. But the number of bees needed to track populations reliably over the whole country makes traditional methods infeasible.
This new research shows how the process could become quicker, cheaper and more accurate. Continue reading
