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The value of bats

cute bats
Apart from being amazingly cute!

Exactly a year ago today I conducted my research on British bats around North and West Yorkshire regarding their habitat selectivity across multiple scales in rural and urban environments. I still can’t believe how fast it’s all gone in the past 10 months! I will be posting up some articles on exactly what I did and how you can also get involved with conserving these fascinating little mammals of ours too, but first I want to tell you WHY bats are so important to us all.

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Just hangin’ around… Pipistrellus pipistrellus (Common Pipistrelle)

Apart from justifying the value of bats in terms of their diverse nature and unique evolutionary history which has lead to the only powered flight seen in mammals (Fenton et al, 1997), bats provide a range of ecosystem services and benefits to both the environment and humans (Altringham, 2011). The Brazilian-free tailed bat provides one of the largest-scale suppressions of insect pests in the world (Kunz, 1989). During their migration northwards each spring, Tadarida brasiliensis forage on cotton bollworms, saving the US economy over $23 billion dollars in terms of preventative damage to cotton and the reduced cost of less pesticide use (Cleveland et al 2006).

tad maps bats

In Asian markets, over 70% of the fruit sold is pollinated or seed dispersed by bats, in particular the Durian fruit which is worth $2 billion (Kasso & Balakrishnan, 2013, Altringham, 2011). The alcoholic beverage, Tequila is derived from the Agave tequilana and is pollinated by the lesser-long-nosed bat, providing a source of income of for many Mexicans (Kunz et al, 2012). Guano is a source of high concentrations of phosphorus and nitrogen, which is one of the primary limiting nutrients of plant life. Deuchamp et al (2009) studied the potential benefits of the ‘pepper shaker-effect,’ a hypothesis where bats flying from nutrient-rich regions to nutrient-poor habitats, redistribute the guano and act as a mobile fertiliser. Several countries sell guano as fertilisers and can be a main source of income in poorer regions (Altringham, 2011).

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The lesser-long-nosed-bat hovering over a cactus flower.

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Ecotourism also boost the economy, for example as seen in Congress Avenue, Texas which generates $12 million annually (Pennisi et al, 2004). Medicine is also derived from the Vampire bat’s salivary enzyme, desmoteplase which acts as an anticoagulant for post-ischemic stroke patients (Furlan et al, 2006). This was initially trialled on mice in 2003, and was found to extend the time required to administer tissue plasminogen activator during the post-stroke period from 3 to 9 hours (Schleuning et al, 2008).

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Molecular structure of desmoteplase.

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Other aspects of bat biology providing benefits to humans include the development of the ©UltraCane, a device that enables the blind to detect oncoming objects. Developed by researchers at the University of Leeds, it was based on the echolocation calls of bats and has helped thousands of visually impaired people (Scheggi et al, 2014).

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The Ultracane

Also mentioned is their value as bioindicators of the overall health of the ecosystem, which can be seen with their importance in ecological networks and high trophic level, if removed, cumulative and rippling effects can be seen lower down trophic cascades (Jones et al, 2009).

I hope you can see how incredible these little mammals are, and stay tuned to find out about the amazing world of bats in future posts!

Check out our Ecosapien video on bats:

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Darwin VS Mendel: Scientist showdown

‘Who has made the greatest contribution to biology, Gregor Mendel or Charles Darwin?’

There is no doubt that the irrefutably intrinsic contributions of both these remarkable scientists enabled future generations of scientists to make further advances in biology which has shaped our lives worldwide; but to what extent does Charles Darwin’s theory of evolution and natural selection or Gregor Mendel’s set of laws of inheritance outweigh each other in terms of importance?

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Charles Darwin (1809-1882) was ‘a man born to explain the astonishing diversity of life and in doing so would revolutionise the way in which we see the world and our place in it.’ Indeed a revolutionary biologist, his pivotal idea was to be inspired on his journey to the Galapagos in 1835 aboard the HMS Beagle. Darwin collected a plethora of different species and meticulously noted minute differences between the species of the Galapagos and the mainland of South America. The evidence suggested that each species had not been independently formed by a creator but had diverged from a smaller group of common ancestors within the major animal kingdoms (Bowler 1983). His ideas of natural selection developed during 1837-1838. The proposed theory stated that in all species limited resources lead to a struggle for existence either between or against other species members, this is known as intraspecific and interspecific competition (Fullick 2008).

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Variation within species influences the success of an organism; therefore species with more advantageous ‘variations’ will live to reproduce and pass on these useful characteristics to their offspring and will better enable it to survive in its particular environment; this is natural selection (we now know that variation in genetic terms means advantageous alleles which occur due to DNA mutations, gene flow and sexual reproduction). This process over time would lead to the elimination of the lesser adapted species and the survival of the better adapted ones and possibly a new species (this is known as evolution, however, Darwin did not directly call his theory this).

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It took 22 years after his voyage to the Galapagos, armed with a wealth of knowledge and a mountain of evidence to publish the world-famous Origin of Species in 1859 (Shanahan 2004). It is clear today that the extent of Darwin’s contribution of his theory of natural selection has greatly contributed to biology. We are now fully aware of the interconnections between species and how we evolved over time. This also lead to the discovery of continental drift, the ‘missing links’ within our earths history through fossil records, the age of the earth itself and inspiration for other biologists. Professor John Shine from the Garvan Institute of Medical Research stated that “Darwin’s theory was a fundamental building block for all modern biology…underpinning the way we think about a lot of medical and biology research” (Arnott 2009). Also in agreement of Darwin’s achievements is Professor Tim Flannery who concluded that what Darwin has done for modern science and indeed every living individual on the planet is “give us the context that created us” and I am inclined to agree with both leading scientists (Arnott 2009).

welcom to galap young darwin

However, many critics of Darwin argue that his contribution was not as great as that of Mendel’s and that Mendel was the ‘father of genetics’ (Mawer 2006). Gregor Mendel was an Austrian monk and biologist who experimented with peas. Quite like Darwin, he was a nature enthusiast and studied at the University of Vienna before returning to priesthood in the Augustinian abbey (Montgomery 2009). It was at the abbey where he began his famous experiments with peas. Between 1856 and 1863 he grew and observed more than 28 000 pea plants and identified seven characteristics showing discontinuous variation including flower position, pea colour and pod shape (Fullick 2008). He experimented by crossing the pairs of peas and recorded which characteristics were passed down onto the next generation, later presenting his results to the Brunn Natural History Society. In 1866 his papers on the subject were published describing the two fundamental laws of hereditary; these are known as Mendel’s Laws of Segregation and Independent Assortment.

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Mendel helped us recognise how organisms passed on their traits to their offspring. His idea of genes was as “discrete particles passed on intact from parent to offspring” (Walsh 2012) and although his great achievements were not noted until 16 years later by Hugo de Vries and Karl Correns, the significance of Mendel’s discovery has enabled our modern society to function as his research laid the foundations for the study of genetics. The Human Genome project for example was created as a multinational project to determine the base sequence of the human genome and many new ones have been identified such as those responsible for disease (Skinner and Lees 2009) which has lead to the development of target drugs benefiting millions globally. Mendel had read Darwin’s theory with interest but pivotally disagreed with the blending notion (Pangenesis- where both parents contribute fluids to the offspring containing the genetic material which is blended to create the new offspring, Walsh 2012) and this is the main reason for many why it was Mendel who was the greatest contributor to biology as he had no ‘gaps’ in his evidence (Leroi 2009). However, I would argue that although Darwin had difficulty in comprehending inheritance, part of his genius was to realise that not understanding inheritance was not a predicament for his theory of natural selection and he had sufficient evidence for it from his work on domesticated animals and plants as well as from communicating with other scientists.

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The world’s most influential biologists, “Darwin and Mendel were contemporaries to many and yet the initial acceptance of their ideas suffered very different fates” (Walsh 2012). Darwin theorized evolution and its complex traits (concepts from population and quantitative genetics) whilst Mendel was concerned with the “transmission of traits from a genetic basis.” Combining Darwin’s theory of evolution with Mendel’s genetics was the most important breakthrough in biology as it triggered a cascade of a whole host of other biological discoveries including DNA (Mayr 1997) the understanding that bacteria evolve which has enabled us to devise methods of dealing with the diseases that they causes and also the disentanglement of the complex relationships between animals and plants within communities enabling us to foresee some of the consequences when we start to interfere with them. I have found both these remarkable scientists profusely influential in my life and to many of my heroes. I therefore collectively deem both of these extraordinary biologists of equal importance in their contributions to biology, because not only have they revolutionised modern biology, they have inspired countless generations to further pursue  scientific knowledge, which is fundamental to the survival, well-being and enjoyment of future generations to come on an ever-changing planet.

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However, our planet is changing. Although natural phenomena have always influenced our climate, the surmounting evidence is unequivocal – Homo sapiens’ ignorance and reckless activities have caused a colossal shift in the natural order and balance of our ecosystems and inevitably the animals that previously co-existed within them. Threats such as climate change, the introduction of invasive species and habitat loss have decimated animal and plant species numbers over the past 100 years to such an extent that nevermore so has the study of zoology been pivotal in understanding the complex interrelationships between specie physiology, behaviour, evolution and development in order to protect their very existence. To be able to understand the intricate relationships animals have within their environment and observe their interactions within it is truly a blessing. I have been enchanted by all organisms from a very young age; to study them in depth would be a privilege and would give me the opportunity to return the same fulfilment by protecting them for future generations to see.

Major threats facing keystone species and the consequences for biodiversity

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Tania R.E –Esteban 1

School of Biology, Faculty of Biological science, University of Leeds, UK, LS2 9JT

 

The global threats facing keystone species is significantly impacting levels of biodiversity, due to the disproportionate effects keystones have on entire communities. They influence trophic interactions and provide ecosystem services of vital importance to the economic, social and cultural well-being of humans. It is therefore in our interest to establish the threats, the individuals most at risk, the potential cascading effects on ecosystems and how we are to manage them successfully in terms of reintroduction or mitigation. In this essay I review the major threats to a variety of different keystone species (at all trophic levels), examine how this influences levels of biodiversity and what effects they have on entire ecosystems. I also evaluate the current and potential management strategies that facilitate networks and allow them to be more resilient to future environmental change. Our knowledge of the concepts that underpin the fundamental basis of ecology can help us confront this as one of the greatest challenges in ecology.

Concept of Keystones

In different ecosystems, each specie plays a role within a community and can influence levels of biodiversity. However, the relative impact of each species can vary in terms of importance [27]. Such species that have disproportionate effects on ecosystems are known as keystone species [39]. According to network theory, keystones are intimately linked via ecological networks of highly connected and complex webs (Box 1, [9]). These include species at different trophic levels. Apex predators exert top-down effect on these levels, known as trophic cascades; whereby these strongly connected species indirectly influence community structure and ecosystem function [37]. The robustness of food webs to species removals varies, depending on the species and ecosystem type, where certain removals have greater impacts on ecosystem functioning and structure. Many apex predators are classed as keystone species because of the secondary extinction impacts of their removal on other species [7]. Predators directly impact upon herbivore numbers as well as indirectly through risk effects [34]. This then influences the relative abundance of producers- hence a ‘cascading effect.’

trophic cascasde

Equally, predators sustain levels of biodiversity via the suppression of other competitors (mesopredators) through competitive exclusion, and allow other species to co-exist [20]. Predatory release occurs when the apex predator is removed, increasing populations of the less competitive mesopredator. This then leads to a decline in its prey. Predator-prey dynamics as well as competition between intra and interspecific species also influence the structure of the food webs [1, 27]. The length of food webs can also greatly influence the direction of the cascade according to the exploitation ecosystem hypothesis [11]. These natural processes can be perturbed by threats to apex predators- whereby the removal of such keystone species leads to the concept of trophic downgrading [10]. As well as this, there is an alternate stable; where ecosystems are disturbed to such an extent that the cascade shifts from its prior state to another- when a tipping point is reached [10].

Box 1- Network theory

The fragile nature of ecosystems has been explored by Sole and Montoya [36], on the basis that if the nodes that connect individuals are randomly removed in a network, it remains stable. However, when highly connected individual are removed, this results in cascading effects and interference throughout the rest of the network. These keystone individuals form the framework and structure of the network. In real ecological networks, strong evidence for the removal of predators are known to not only directly impact its prey, but also have indirect effects via top-down forcing. Ecosystems processes such as primary production, nitrogen cycling and the establishment of invasive species are also affected (Figure 3 [10]).

network theory

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Keystones – threats to a complex web of interactions

Habitat destruction

There have been major declines in biodiversity within recent decades, in what has been described as the 6th mass extinction event [27]. The threats facing keystones and the ecosystem services they provide are predominantly anthropogenic [19], and habitat loss is arguably one of the greatest [15]. For example, the Yellow and Black-Casqued Hornbills are both in decline, which has been correlated with deforestation in Nigeria as well as forest sections along the Ivory Coast [28]. This is problematic in that the genera Ceratogyma are key seed dispersers of fruiting trees, and play an important role in maintaining the heterogeneity of forests and species diversity via gene flow [28]. Because of the large spatial distribution of their territories [45], up to 22% of lowland tropical rainforest species are dispersed by the 3 hornbill species within this genera [23]. Cultural ecosystem services include traditional ceremony wear as well as other benefits to the keystone tree species, Ficus, which in turn provides economic services to local tribes’ people. It is also an important food source for other species within the ecosystem [23].

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Urbanization

Other threats to keystones include the urbanization of many habitats. Increased contact between humans and species drive them to exhibit behavioural plasticity and alter their behaviour [33]. A majority of studies indicate that increases in urban environments decreases species richness [35], due to disturbances in breeding patterns, anti-predator behaviour, fitness, selection of habitat and overall population size. This has cascading effects along trophic levels [2]. The black-tailed prairie dog, a keystone specie, contributes to the health of steppe habitats by mixing the soil. This increases plant productivity and landscape heterogeneity as well as providing coyotes with a food source [3]. Their overall numbers have decreased as a result of increased urbanization. However, in contrary to the risk-disturbance hypothesis, where increases in anti-predatory behaviours (such as vigilance) are seen, some populations exhibiting behavioural plasticity have reduced their vigilance due to habituation [12]. This has negatively impacted the vegetation due to increased foraging time, which has ‘rebounding’ effects back up the trophic cascade, on other herbivores and predators [33].

Climate change

Complex plant-pollinator webs are also disturbed by habitat destruction due to their sensitivity to perturbation [29]. This is the case with the keystone plant mutualist, Heliconia tortuosa,

Figure 1. The warming trend set to continue: (Left) Projected increases in temperature by 2081-2100 if mitigation and use of renewable resources is adopted. (Right) These are the predictions if the business as usual strategy continues (source: IPCC, Fifth assessment, 2014).

IPCC

which supports a variety of hummingbird species, and is considered a central node in this web interaction [17]. Recent work has provided evidence for the fragmentation hypothesis, where forest composition is fundamental to the reproduction of H. tortuosa. Thus, the reduction in heterogeneous landscapes due to deforestation is thought to alter both plant distribution and pollinator behaviour, leading to declines in both populations [29]. Equally, other systems have also shown that deforestation alters pollinator behaviour. Phaethornis hummingbirds will take longer flight paths to avoid deforest patches and agricultural landscapes, decreasing pollinator efficiency. This affects the survival of plant species dependent on this mutually beneficial ecological interaction- and has led to regional declines in biodiversity [16].

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Climate change also poses a major threat to the biodiversity of keystone pollinators (such as bats, bees and birds [19]). One third of the world’s crop production is met by the ecosystem services provided by insect pollinators [30], with agricultural pollinator services estimate to be worth £120 billion per acre, annually [40]. Phenological shifts are also increasingly being observed, with the impact evident in both pollinator and plant keystone species [4]. In Japan, seed production in Corydalis ambigua and Gagea lutea decreased due to the warmer temperatures causing them to bloom earlier, resulting in phenological mismatching with its key pollinator, Apis Mellifera. Consequently, this reduced pollination efficiency and success [31]. Climate change has also altered bee distributions and caused phenological shifts in their flight period. Predictions suggest that the spatial shifts in bee movements will be faster than that of its food resource, also causing phenological mismatching and decrease wildflower pollination [4]. Therefore, climate change poses not only a threat to the keystone plant-pollinators, but to other communities dependent on wildflower meadow species [31]. This highlights the fragility of these mutualistic interactions as key nodes in an ecosystem, due to their varying response to temperature change.

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A major issue with climate change is predicting the influence it will have on biological communities in the future [13]. The polar bear (Ursus maritimus) is an apex predator in the Arctic ecosystem which is very sensitive to changes in sea ice cover, where it hunts, migrates and reproduces [25]. The rate of temperature increase in the Arctic and northern regions have doubled in recent years, reducing sea ice cover [24]. In particular, over the past 30 years, the Western Hudson Bay has seen earlier ice break up as well as reduced snow fall (Figure 2). The impact on ringed seals (a keystone specie) with longer ice-free summers has subsequently lead to changes in polar bear behaviour [25]. The continuity of this pattern threatens seal pup survival as they are forced to swim for longer periods of time in open water, exposing them to predation [13]. Ringed seals provide polar bears with net wet weight calorific gains of 2.2-5.3 kcal/g [43], and the decreased recruitment of ringed seals has driven polar bears to target nesting birds, as they are unable to gain sufficient energy [25]. This warming trend is set to continue with possible increases in temperature of 5.0-6.4˚C by 2081-2100 (Figure 1, [24]).

Figure 2: Sea ice extent between 1979-2012 throughout the summer months. Evident loss seen annually. (Source: Iverson [25]).

Hunting and over-exploitation

Hunting and over exploitation is also a prevalent threat to many keystones worldwide. The removal of a keystone predator is a major cause of secondary extinctions, demonstrating the strong influence of top-down effects on lower trophic levels [10]. This was seen with the expatriation of the Grey wolf in Yellowstone during 1935 (due to hunting), which increased populations of elk as a result of predatory release [39]. Increased levels of browsing on aspen, cotton and willow saplings in riparian river systems led to a more homogenous landscape and reduced diversity [34]. The wolf played a vital ecosystem role by maintaining diversity as well as healthy numbers of mesopredator populations. Classic studies of the consequences of predator removal are also illustrated with sea otters [10]. Enhydra lutris was nearly hunted to extinction by Russian fur traders at the beginning of the 20th century, resulting in the predatory release of sea urchins, which reduced Kelp forests by intensively over-browsing [42]. However, with the return of the otter during the 1970’s to certain areas, the recovery of the kelp forests was observed due to the effects of top-down control on urchins. The kelp populations in regions where otters were unable to recolonize did not recover [11], demonstrating how the impact of hunting can alter and result in the simplification of food webs.

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The general pattern of global declines in apex predators is a cause for concern, due their strong connectedness in ecosystems and influence in altering the stability of food webs [19]. This is less well studied in marine ecosystems [20]. For example, sharks are apex predators in marine ecosystems [22], and are threatened by hunting. Demand for shark fin during the 90’s increased mortality rates by 80%. Many debate the function of sharks as keystone predators [8], however more recent studies suggest that although not all shark species can be described as keystones, some are key in structuring some ecosystems [44]. Indeed, strong arguments made by Estes et al., [10] concluded that the top-down effects exerted by apex predators are equally as influential as bottom-up effects. In Western Australia, Tiger sharks are considered a keystone apex predator; as mesopredator diversity (dolphins) and herbivores (dugongs) abundance are indirectly affected by the “seascape of risk,” as well as by direct predation [20]. 15 years of data collection in Shark Bay has supported the idea that the non-predatory effects of top apex consumers (predator keystones), play a pivotal role in influencing ecosystems [10]. Thus shark declines are affecting mesopredator numbers and behaviour, with unknown consequences on the rest of the aquatic communities [44].

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Clearly, hunting apex predators can have detrimental, aggregating effects on lower trophic levels, both directly (via predation) or indirectly (through the landscape/seascape of fear concept). Equally, the idea that keystone’s play a role within and across communities [27], was seen with the decline of sea otters in the Aleutian archipelago populations due to increased predation by Orca [42]. The overexploitation of fish stocks in these waters in turn reduced populations of pinniped that fed on them [11]. This altered the orcas behaviour which began targeting otters as an alternative food source. Kelp forests once again declined as urchins were free of predation. This is known as the exploitation ecosystems hypothesis, where the food-chain length determines the level of influence and control top-down or bottom-up systems have in the primary productivity of ecosystems [10, 11].

Great White Shark

Future: Management, mitigation and reintroduction

Problems

In terms of keystone species, the challenges of managing and mitigating their decline arise due to the complexity and interconnectedness between the many species they affect within ecological communities [5]. For example, managing the declines of seed dispersers is hard due to the large spatial ranges of their territories and difficulty in quantifying dispersal rates [23]. The extent to which urban-adapted keystones will affect the rest of the community depends on their ability exhibit behavioural plasticity and adapt, which varies between species and landscape scale [35].

The threat of climate change is also difficult to predict, thus is hard to prevent plant-pollinator loss in the future as phenological shifts continue at different rates [4]. Similarly, the uncertainty surrounding model projections of sea ice loss threatens the future survival of many Arctic species [25]. In aquatic systems, the lack of protection out of marine conservation areas and the extensive movements of keystone predators such as sharks, creates problems in managing and mitigating their decline [21, 22].

Equally, the overall concept of what constitutes a keystone species provides difficulties in management [7]. The definition can be broadly used to describe a spectrum of keystone types, which is confusing and problematic for conservation policy [7]. With an increasing number of species being given ‘keystone status,’ the lack of consistency in defining them more scientifically is rapidly becoming a challenge in itself [27].

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Identification of which trophic direction is most influential in affecting levels of biodiversity within communities is controversial [10]. Often, it is dependent upon the ecosystem as well as the keystone specie. Some argue that primary production controls ecosystems bottom-up [18]. Others believe predatory top-down control is more influential, and is currently gaining more support due to the mounting evidence that global predator declines have significant impacts on communities and ecosystem processes (Figure 3, [10]). However, even if top-down systems were recognisably more important in structuring ecosystems, it is hard to determine the most prevalent impact predators have in influencing interactions within food webs- directly (through predation/lethal) or indirectly (risk effects/non-lethal [34]).

Figure 3: Indirect impacts of apex predators on different ecosystem function and processes (Source: Estes et al [10]).

Indeed, this is the case with sharks, where the importance of risk effects might be underestimated [26]. In terrestrial ecosystems, the ‘landscape of fear’ as well as direct predation by wolves is being taken into account in studies of natural systems, (eg: Białowieża Forest, Poland) in order to consider the nonlethal effects on herbivores [32]. Proposals by Manning et al., [34] suggest that controlled experiments in the Scottish highlands would provide much needed data and viable evidence for their reintroduction. However, public opinion is often divided in terms of reintroductions [37], and the funding and costs of trial experimentation are deemed wasteful [32].

The nature of predicting ecosystem response with the removal of a keystone is also very difficult when taken from a stable environment- where prior knowledge of the response in unknown [36]. Only a few studies have examples of networks that are partially mapped [5], and the substantial lack of data on a range of ecosystems makes management difficult [36]. Much earlier research does not indicate the strength of each trophic link, thus it is difficult to compare to the current consistent and empirically accurate data. Even when disrupted, other factors such as intraspecific competition can alter the response, and may take many years for the effects to propagate in the ecosystem [10]. Current strategies by the US Endangered Species Act fail to incorporate this [41].

Possible solutions?

It is vital that scientists are able to quantitatively asses the relative contribution of each proposed keystone [36]. Only then can policy makers implement management strategies that target and focus on protecting species that have the most important functional role- rather than the rarest specie [27]. We must also therefore demonstrate their functional importance before policy-makers act on the impetus of the analogical term of a keystone [7]. Of equal importance is understanding the connectivity of networks as well as attempting to mitigate the threats facing keystone apex predators. The geographic spatial scales at which natural or previously manipulated experimental removal experiments varies enormously, thus must also be considered in future reintroductions and management plans [39].

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As already established, complex ecological concepts are hard to manage as many factors feed into the function, stability and persistence of food webs; including biotic and abiotic factors [10]. It is clear how important abiotic interactions greatly influence ecosystems and community structure and function, and must be considered if we are to manage and mitigate the effects of current and future climate change [19]. Therefore, as the fifth assessment by the IPCC suggests, anthropogenic climate change policy should focus on mitigation by following resilience pathways and realising adaption measures towards a more sustainable future [24]. If we are to reduce the number of extinctions, policy must also address the source of the problem; fossil fuel consumption, to mitigate the severe effects it could have on vulnerable keystones and their habitat [24].

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Other concepts such as network theory have helped explain how the systematic targeting of particular keystone individuals is far more destructive than random removal [36]. Therefore fisheries must implement this into their harvesting methods and reduce their impact on sharks by implementing annual moratoriums to prevent over harvesting. This will require international cooperation to account for the spatial movements of these keystone predators [44].

Conclusion

The threats facing keystone species may arguably have the greatest impact upon ecosystem function and stability globally [10]. Keystone predators in particular play an important role as their loss is a cause of many secondary extinctions [21]. The complexity of these networks cannot be undermined, and scientists must now be able to predict and further assess why certain keystone species are more robust or more at risk from collapsing early on than others. This will determine which species will have the greatest impact upon the stability and function of communities [46]. Additionally, completion of fully described networks will need to be of a multidisciplinary manner, in order to expand upon the current knowledge of these systems. Mitigating the threats as well as assessing the success of keystone reintroductions in influence levels of biodiversity is also key [44]. The reduction of harmful human activities is also necessary in order to prevent future extinctions and declines in biodiversity [24]. Ultimately, the solutions to the challenges facing keystones and ecosystem function are not simple. However, further knowledge of how these systems work and the implementation of efficacious management strategies will lead more efficient restoration and protection.

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Demystifying Dementia

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This event was all about raising awareness about the devastating disease- Dementia. I really enjoyed communicating this fascinating but equally important scientific topic to a diverse audience, ranging from 4-90+. Science communication is becoming ever more so a prevalent skill for upcoming scientists who wish to elucidate their research and the work of others to an audience who have not been fortunate enough to conduct the research themselves or learn from those that have. Dementia is affecting older people every year as well as younger people (it was previously thought that 17,000 young adults had dementia, this was an underestimate and it has since been found that 40,000 have the Alzheimer’s disease). Dementia costs the NHS £26.3bn overall, and the government is considering imposing care tax to pay for the shortfall.

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This, I believe, is an injustice to the victims of a disease where no definitive cause has being established. It is wrong to enable health free care to patients with heart conditions for those who have led an unhealthy lifestyle, and deny the right of the elderly who have paid into the systems for many decades and led otherwise, healthy lives. I talked about the symptoms, causes, diagnosis and possible treatments successfully and reassuringly to the audiences, as well attempt inspire younger public members to keep fit and lead an active life… some inparticular were more eager than others! One girl would not stop having a go on the exercise bikes! I am a passionate sportswoman and really enjoy having a healthy lifestyle, and I wanted to share my experience with others and encourage them to live a fitter and more exhilarating life through exercise.

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Before I go on, here are some quick facts about what Dementia actually is:

# 1 What is Dementia?

It is a set of symptoms as a result of several diseases such as Alzheimer’s, Lewey Bodies, Fronto-temporal and Vascular dementia which cause the typical set of symptoms such as:

-Loss of coordination

-Difficulty of remembering times during the day, appointments

-Difficulty with speech, slurring words

Uncoordinated movements

Confusion, fear and anxiety

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Depending on which disease has caused the specific set of symptoms, they can vary enormously. This is why it is VITAL to go to your GP to check this out. They will run a thorough set of checks: blood tests (to see if there is another cause, for example side effects of medication), CAT and MRI scans of the brain, physiologist will perform mental tests to see how the brain copes as well as other in-depth memory tests. There is plenty of info on their website: http://www.alzheimers.org.uk/

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The event was very rewarding and I believe the general public also felt that they had a great experience. The first day on the Saturday I was a little nervous, however as people began asking questions and showed genuine interest I really enjoyed myself, and Sunday I had “rehearsed” the talks. The range of different ages of general public members was large and certainly more interesting. What did work very well was the How brains work stand, with the rat/mouse/snail brains and neurone pipe cleaners, the children were simply enthralled and fascinated by these real life organs, and the younger children were delighted to have something soft and colourful to make and then take home. The adults, to my surprise, asked quite a lot of questions with regards to the symptoms and diagnosis of dementia on this table, which I had prepared for with the excellent notes provided on the Alzheimer’s society website.

The How Science works stall with the chromatography and gel electrophoresis was a bit hit, with the widest range of ages all participating on both activities. We had so many people at one point that we ran out of chromatography paper! We got the children to try a fusion of different patterns and colours from the chromatography which they loved, and the creating of a role play scientist really got them engaging with us and participating in the pipetting of the food colouring in the wells. The thought of dressing up as a scientist for many was the most fun out of the activities on the table, and parents enjoyed taking photographs of them.

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The multi-coloured chromatography designs were dried and stuck into their activity books to keep and show to their teachers; these booklets were most definitely popular and a good motive for the children to keep going around and get involved in all the activities. It was extremely rewarding to see the delight on their faces as they saw what they had created. When praising them for their work they were more willing to try out new activities and ask questions.

What didn’t work as well was the larger neurone which involved more children, it wasn’t as entertaining for them, and they felt slightly more embarrassed than doing the pipe neurones. I think in the future face painting would be a very good way to engage children and keep parents at the event for longer. BBC One show presenter Marty Jopson was also there with his children and wife, so that was a surprise! His children clearly had his love and passion for science, and were particularly good at the exercise bikes and blood pressure monitor testing.

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Having to tailor information for particular age group was initially challenging, but then as I gained more practice at it, I felt more confident in toning town the level of complexity for younger groups, then increasing it again for adults, and more so for academics. I certainly felt more confident in communicating with a broad range of people as well as approach people rather than wait and hold back for people to communicate with you. I never thought that I would be able to relate to children in a scientific manner which I did, and I truthfully felt rewarded when children were inspired and excited by the science we were explaining to them. I had to remember how to use my artistic side, having created a staggering 36 neurones! I really enjoyed myself and look forward to participating in some more, possible even consider leading an event now that I feel more confident.

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Having read up on Dementia and the diseases that cause it has giving me a new found interest in the science behind it, the proteins that cause such damage- talking to the PhD volunteers was interesting and I believe I have learnt a lot about the disease. It has inspired me to go on to do a 5k run for the Alzheimer’s society, and help those in need of care- it really is a good cause and I hope I can do my bit.

Here is the link to the Leeds University web page- the team of researchers are doing an AMZING job of trying to combat this deadly disease: http://www.stem.leeds.ac.uk/ai1ec_event/healthy-brains-leeds-demystifying-dementia/?instance_id=

Almscliff Adventures: Begginners guide to Rock Climbing

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Almscliff Crag is located between the verdant green sloping hills of Harrogate and the bustling city of Leeds, and protrudes on top of a small hill. Made of Millstone grit, it optimizes the hardiness of the great Yorkshire people- tough and gritty is most certainly the way up North! It was formed out of the destruction of the surrounding softer and more fragile shale and mudstone strata, which left this hardier famous landmark which is extremely popular with walkers and climbers alike. I headed up with the Leeds University Mountaineering society (Climbing) to try out my first outdoor climb, having had several indoor and seemingly difficult routes indoors at the Depot (Pudsey) and The Edge (Leeds). I could only really manage the Blues and Black holds at that point, so wasn’t too sure what to expect on an outdoor trip! But I was rearing to go and try it out.

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Beautiful views of Otley and the Chevin from the top of the Almscliff crag.

Ed and Dan were my teachers and were incredibly patient with my incompetent movements that resembled a seagull with broken wings that had been coated with tar… rather flailing!

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But you learn fast, it literally is a steep learning curve, with all the different names for pieces of kit, it can be a bit overwhelming! Firstly, rock climbing involves two people or a small group including the use of ropes which can either be done indoors at a local climbing centre OR outdoors. Other types of climbing without ropes involves bouldering where crash mats are places strategically in order to prevent any accidents. This is usually done in indoor centres without rope as the crash mats provide sufficient padding to cushion a fall whilst you build up your strength and stamina, to prepare you for an outdoor climb. You can use ropes indoors where another person is strapped into a harness and tied up whilst one person belays you- basically pulling up the slack rope as you climb ever higher and ready to catch you if you slip and fall. The different types of climbing are:

# 1 Traditional (or trad if you want to sound cool and mingle with climbers, ALWAYS use colloquial language to get in with the climbers!). This is where one climber will “lead” up along the rock face and place in all the bolts, cams and screws through which the rope will be placed through. This not only keeps the lead and first climber safe but allows the second climber to follow. Then at the top an anchor is built and three ropes are attached with into the rock with hexes (you will see why, they resemble hexagonal metal pieces) and then attach yourself to them by the rope with a special type of knot know as a clove hitch. The second climber will follow up after the first has yelled “OFF BELAY, FREE TO CLIMB” and they have secured the ropes up at the top. The second climber will also remove the gear as they progress.

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(Left) Your nuts, bolts, cams and clip ons to keep you safe! All of this should be provided with your climbing society. (Bottom) Nick Belaying Fergus, (Bottom Right) Nick being lowered by the belayer, Ed who is at the top.

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# 2 Sport climbing is where climbers clip onto already placed bolts that are securely fixed into the rock for people to ascend. This is the much easier and quick way to climb, but not as exciting as leading a climb.

#3 Soloing is where climbers will ascend under their own steam without any rope and by themselves, DON’T TRY THIS FIRST!! It can be very risky going it alone, so make sure you have many months of experience before you try this out. Ed, (see below) has done this for years and so is experienced enough to know the risks.

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Ed soloing it up the Chimney

#3 Ice climbing involves, as the name suggests, ice or snow with use of particular equipment such as ice picks (who doesn’t want those awesome looking pick axes?) as well as crampons, boots, thermals, rope and harness. This isn’t for the faint hearted, not only are the cold conditions tough, but the technique is better off perfected indoors before you go out there, but it looks beautiful.

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# 4 Competition climbing is more competitive climbing primarily done indoors in climbing walls, check out these amazing videos of insanely good comp climbers!

https://www.youtube.com/watch?v=8Qk-lNsRtwQ

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# 5 Bouldering is as I mentioned earlier without ropes, and is frequently performed indoors with different coloured holds which indicates their level of difficulty. Hand Jamming, crimps are all part of the technical lingo…watch out for the Climbers chat guide coming soon!

IMG_5325Here is Fergus Bouldering up Manhorn…quite a long way down so crash mats were used! I was going to do this but then again….

Here are the essential basics to Traditional climbing:

#1: Belay Kit– can be bought in many outdoor stores, I personally bought mine at GO Outdoors as you can get a £5 discount card which will save you a whole load, and my gorgeous black and orange harness as well as purple screw gate (to clip rope through) and orange belay device (where the climbers rope is threaded through and to control the climbers ascent/descent). This will usually set you back £50 with all of the above and a chalk bag for when you get sweaty palms! If you have a bit more cash to splash, you could probably get a harness for £46 alone then buy the rest of the gear separately. Check this Climbex one similar to the one I got on Go Outdoors.co.uk:

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http://www.gooutdoors.co.uk/climb-x-pilot-harness-set-p194186

#2 Climbing shoes- I can’t stress how IMPORTANT SHOES are… always get a size above your normal shoes size, as they can be quite tight! It is supposed to be just uncomfortable so that you can really grip the rock face and have the friction to push up against gravity and the wall. Also you want them to be super comfy!

http://www.gooutdoors.co.uk/climb-x-crux-climbing-shoe-p194484

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#3 Chalk– is placed into you bag and attached to the back of your harness, used to stop those sweaty palms of yours when you’re up high from sweating up and losing grip!

The cheapest and best way to start climbing is to join your local university club and pay the membership there: your covered for insurance purposes and can borrow all the gear for a small £30 a year…think how much you will be saving if you don’t have to buy all that rope, harness, shoes, cams, nuts, clip ons, ect!

It’s also a great way to make friends and get shown how to climb with a good technique. Most members would have been doing this sport for some time and are experienced. So don’t splash your cash on all these fancy pancy climbing courses all the time- although I learnt how to belay at the edge for £25, I could have learnt the exact same thing with the climbing society showing me. I did my first outdoor climb with them too.

IMG_0640Me checking out my harness, belay device and screw gate.

So back to Almscliff! Classic climbs include the Chimney which is categoriesd as very difficult and Wall of Horrors. But as a beginner I would highly recommend doing Stewpot and Easy man– I am seen here doing Stewpot, which I also led a climb for. The rock is lovely and firm here which is reassuring, but it really makes you move your body in a way that makes you a more cautious and perceptive person. You need to be aware of where you’re placing your feet at all times…if you get a bad foothold then finding an equally dodgy handhold is of no significance.

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TRUST in your strong powerful legs and push up always from them and straighten your body right from your feet, all the way through your legs, through your core and UP you go! Onto the next hand hold. I must say, when I first started climbing, I had my doubts whether or not I could do it. My arms are like spindly gibbon arms, not much muscle at all! My legs are strong with all the cardio I do, and I was assured that it’s your LEGS that are the key to climbing. Whilst climbing Stewpot, in one of the cracks my friend shouted out that he saw a bat! I had to come up as I must say I didn’t initially believe him! But indeed there was a small wrinkled up Pipestrelle, sat snuggly between the cracks. We wondered if he was dead but he stirred as soon as we took a photo of him. Hope he was alright. You need a special license to handle them so it’s best that we left it alone. One then route had been led for me and it was safe for me to climb, I tied up my harness and headed up.

It was a gorgeous warm and sunny day. 25ᵒC-perfect for climbing the warm baked rocks of Almscliff crag. The scenery is truly spectacular up there. You can see why it’s a popular haunt with climbers, ramblers, boulderers, painters and walkers. Prior to joining the group, on my way up from the side car park, I wandered the crag to get a couple of panorama shots, and found a whole host of insect wildlife there. Swallows dart up and down catching their ready packed meals that are equally agile and astute on the wing- talk about fast food!

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My climbing friends tried the much harder Chimney, and Nick and Fergus gritted their teeth, and push and pulled harder to get to the top after attempts to get past the notoriously difficult mid slab of millstone rock- gravity ALWAYS wins. Funnily enough as I am writing this I just watched the film Gravity last night, brilliantly composed and shot, but a rather pessimistic film! Its unnerving to see your climbing buddies take a fall, even when attached to rope that can take the weight of a ton. We shout out support down at the bottom to help spur them on.

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The sun was beginning to slide further down the clouds, providing the perfect opportunity for me to get a silhouetted head shot and create a double exposure- check it out!I was very happy with the results after a tinkle on Photoshop CS3, I will be posting up a video tutorial on how to do it shortly. I hereby name it “Fergus and the Ferns!” after the plant I used to create it and the guy posing for it!

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After a long and gorgeous afternoon of climbing and photography, it couldn’t have ended more perfectly. I OFFICIALLY have the climbers bug, despite the climbers calluses and cramps in your toes after wearing the tiny shoes, climbing really makes you feel alive and brings out the best in your abilities- it MAKES you have to believe and trust in your judgment and work as a team to help them through the climb.

“Nothing beats that feeling when you get your hand at the top of that rock…”

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