Biological Sciences, Department of

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Poecilia picta, a Close Relative to the Guppy, Exhibits Red Male Coloration Polymorphism: A System for Phylogenetic Comparisons

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2015
Abstract: 

Studies on the evolution of female preference and male color polymorphism frequently focus on single species since traits and preferences are thought to co-evolve. The guppy, Poecilia reticulata, has long been a premier model for such studies because female preferences and orange coloration are well known to covary, especially in upstream/downstream pairs of populations. However, focused single species studies lack the explanatory power of the comparative method, which requires detailed knowledge of multiple species with known evolutionary relationships. Here we describe a red color polymorphism in Poecilia picta, a close relative to guppies. We show that this polymorphism is restricted to males and is maintained in natural populations of mainland South America. Using tests of female preference we show female P. picta are not more attracted to red males, despite preferences for red/orange in closely related species, such as P. reticulata and P. parae. Male color patterns in these closely related species are different from P. picta in that they occur in discrete patches and are frequently Y chromosome-linked. P. reticulata have an almost infinite number of male patterns, while P. parae males occur in discrete morphs. We show the red male polymorphism in P. picta extends continuously throughout the body and is not a Y-linked trait despite the theoretical prediction that sexually-selected characters should often be linked to the heterogametic sex chromosome. The presence/absence of red male coloration of P. picta described here makes this an ideal system for phylogenetic comparisons that could reveal the evolutionary forces maintaining mate choice and color polymorphisms in this speciose group.

Document type: 
Article
File(s): 

Ranking Mammal Species for Conservation and the Loss of Both Phylogenetic and Trait Diversity

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2015
Abstract: 

The 'edge of existence' (EDGE) prioritisation scheme is a new approach to rank species for conservation attention that aims to identify species that are both isolated on the tree of life and at imminent risk of extinction as defined by the World Conservation Union (IUCN). The self-stated benefit of the EDGE system is that it effectively captures unusual 'unique' species, and doing so will preserve the total evolutionary history of a group into the future. Given the EDGE metric was not designed to capture total evolutionary history, we tested this claim. Our analyses show that the total evolutionary history of mammals preserved is indeed much higher if EDGE species are protected than if at-risk species are chosen randomly. More of the total tree is also protected by EDGE species than if solely threat status or solely evolutionary distinctiveness were used for prioritisation. When considering how much trait diversity is captured by IUCN and EDGE prioritisation rankings, interestingly, preserving the highest-ranked EDGE species, or indeed just the most threatened species, captures more total trait diversity compared to sets of randomly-selected at-risk species. These results suggest that, as advertised, EDGE mammal species contribute evolutionary history to the evolutionary tree of mammals non-randomly, and EDGE-style rankings among endangered species can also capture important trait diversity. If this pattern holds for other groups, the EDGE prioritisation scheme has greater potential to be an efficient method to allocate scarce conservation effort.

Document type: 
Article
File(s): 

Supplementary Material: Phylogeny of all seeded plant families

Peer reviewed: 
No, item is not peer reviewed.
Date created: 
2015-10-05
Abstract: 

Climate change is driving rapid and accelerating shifts in range limits, both poleward expansions and equatorward contractions.  However, many species are falling behind the pace of change in their dispersal into newly suitable habitats and now show “climate debts”, lags between predicted and observed range expansions under changing climates. Failure to track changing climates may be due to interspecific interactions such as particular food availability for specialists, abiotic barriers such as mountain ranges, or intrinsic traits such as dispersal limitation. A trait-based analysis of climate change performance would help identify causes of climate debt.

To understand the correlates of climate debt within a large clade of organisms we use historical and modern observations of butterflies from western Canada as a case study to construct and project individual climate-based environmental niche models. By comparing projected distributions based on historical records to observed modern distributions we are able to construct estimates of climate debt and evaluate the effect of dispersal ability, diet breadth and a proxy for range size on these species' measured climate debt.

High levels of climate debt are accumulating within the butterflies of Western Canada, independently of dispersal ability, diet breadth and phylogeny. Range size emerges as the only variable that significantly reduces climate debt, suggesting that more narrowly-ranged species may be at risk of being squeezed out by both a reduction of suitable habitat in their current range and the failure to colonize newly available habitat. These findings underscore the need to investigate potential landscape-level determinants of climate debt that may be limiting range expansions in this group.

Document type: 
Dataset

Supplemental Material - 1000 randomly-chosen candidate topologies for the Canadian butterfly phylogeny

Peer reviewed: 
No, item is not peer reviewed.
Date created: 
2015-10-05
Abstract: 

Climate change is driving rapid and accelerating shifts in range limits, both poleward expansions and equatorward contractions. However, many species are falling behind the pace of change in their dispersal into newly suitable habitats and now show “climate debts”, lags between predicted and observed range expansions under changing climates. Failure to track changing climates may be due to interspecific interactions such as particular food availability for specialists, abiotic barriers such as mountain ranges, or intrinsic traits such as dispersal limitation. A trait-based analysis of climate change performance would help identify causes of climate debt.

To understand the correlates of climate debt within a large clade of organisms we use historical and modern observations of butterflies from western Canada as a case study to construct and project individual climate-based environmental niche models. By comparing projected distributions based on historical records to observed modern distributions we are able to construct estimates of climate debt and evaluate the effect of dispersal ability, diet breadth and a proxy for range size on these species' measured climate debt.

High levels of climate debt are accumulating within the butterflies of Western Canada, independently of dispersal ability, diet breadth and phylogeny. Range size emerges as the only variable that significantly reduces climate debt, suggesting that more narrowly-ranged species may be at risk of being squeezed out by both a reduction of suitable habitat in their current range and the failure to colonize newly available habitat. These findings underscore the need to investigate potential landscape-level determinants of climate debt that may be limiting range expansions in this group.

Document type: 
Dataset
Other

Valuing Species on the Cheap

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2015
Document type: 
Article
Dataset

Does the Earth's Magnetic Field Serve as a Reference for Alignment of the Honeybee Waggle Dance?

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014-12-26
Abstract: 

The honeybee (Apis mellifera) waggle dance, which is performed inside the hive by forager bees, informs hive mates about a potent food source, and recruits them to its location. It consists of a repeated figure-8 pattern: two oppositely directed turns interspersed by a short straight segment, the “waggle run”. The waggle run consists of a single stride emphasized by lateral waggling motions of the abdomen. Directional information pointing to a food source relative to the sun's azimuth is encoded in the angle between the waggle run line and a reference line, which is generally thought to be established by gravity. Yet, there is tantalizing evidence that the local (ambient) geomagnetic field (LGMF) could play a role. We tested the effect of the LGMF on the recruitment success of forager bees by placing observation hives inside large Helmholtz coils, and then either reducing the LGMF to 2% or shifting its apparent declination. Neither of these treatments reduced the number of nest mates that waggle dancing forager bees recruited to a feeding station located 200 m north of the hive. These results indicate that the LGMF does not act as the reference for the alignment of waggle-dancing bees.

Document type: 
Article
File(s): 

(R)-Desmolactone Is a Sex Pheromone or Sex Attractant for the Endangered Valley Elderberry Longhorn Beetle Desmocerus californicus dimorphus and Several Congeners (Cerambycidae: Lepturinae)

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014-12-18
Abstract: 

We report here that (4R,9Z)-hexadec-9-en-4-olide [(R)-desmolactone] is a sex attractant or sex pheromone for multiple species and subspecies in the cerambycid genus Desmocerus. This compound was previously identified as a female-produced sex attractant pheromone of Desmocerus californicus californicus. Headspace volatiles from female Desmocerus aureipennis aureipennis contained (R)-desmolactone, and the antennae of adult males of two species responded strongly to synthetic (R)-desmolactone in coupled gas chromatography-electroantennogram analyses. In field bioassays in California, Oregon, and British Columbia, traps baited with synthetic (R)-desmolactone captured males of several Desmocerus species and subspecies. Only male beetles were captured, indicating that this compound acts as a sex-specific attractant, rather than as a signal for aggregation. In targeted field bioassays, males of the US federally threatened subspecies Desmocerus californicus dimorphus responded to the synthetic attractant in a dose dependent manner. Our results represent the first example of a “generic” sex pheromone used by multiple species in the subfamily Lepturinae, and demonstrate that pheromone-baited traps may be a sensitive and efficient method of monitoring the threatened species Desmocerus californicus dimorphus, commonly known as the valley elderberry longhorn beetle.

Document type: 
Article
File(s): 

Measuring Evolutionary Isolation for Conservation

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014-12-10
Abstract: 

Conservation planning needs to account for limited resources when choosing those species on which to focus attention and resources. Currently, funding is biased to small sections of the tree of life, such as raptors and carnivores. One new approach for increasing the diversity of species under consideration considers how many close relatives a species has in its evolutionary tree. At least eleven different ways to measure this characteristic on phylogenies for the purposes of setting species-specific priorities for conservation have been proposed. We find that there is much redundancy within the current set, with three pairs of metrics being essentially identical. Non-redundant metrics represent different trade-offs between the unique evolutionary history represented by a species verses its average distance to all other species. Depending on which metric is used, species priority lists can differ as much as 85% for the top 100 species. We call for some consensus on the theory behind these metrics and suggest that all future developments are compared to the current published set, and offer scripts to aid such comparisons.

Document type: 
Article
File(s): 

Assessing the Effect of Marine Reserves on Household Food Security in Kenyan Coral Reef Fishing Communities

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014-11-25
Abstract: 

Measuring the success or failure of natural resource management is a key challenge to evaluate the impact of conservation for ecological, economic and social outcomes. Marine reserves are a popular tool for managing coastal ecosystems and resources yet surprisingly few studies have quantified the social-economic impacts of marine reserves on food security despite the critical importance of this outcome for fisheries management in developing countries. Here, I conducted semi-structured household surveys with 113 women heads-of-households to investigate the influence of two old, well-enforced, no-take marine reserves on food security in four coastal fishing communities in Kenya, East Africa. Multi-model information-theoretic inference and matching methods found that marine reserves did not influence household food security, as measured by protein consumption, diet diversity and food coping strategies. Instead, food security was strongly influenced by fishing livelihoods and household wealth: fishing families and wealthier households were more food secure than non-fishing and poorer households. These findings highlight the importance of complex social and economic landscapes of livelihoods, urbanization, power and gender dynamics that can drive the outcomes of marine conservation and management.

Document type: 
Article
File(s): 

Species, Habitats, Society: An Evaluation of Research Supporting EU's Natura 2000 Network

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2014-11-21
Abstract: 

The Natura 2000 network is regarded as one of the conservation success stories in the global effort to protect biodiversity. However, significant challenges remain in Natura 2000 implementation, owing to its rapid expansion, and lack of a coherent vision for its future. Scientific research is critical for identifying conservation priorities, setting management goals, and reconciling biodiversity protection and society in the complex political European landscape. Thus, there is an urgent need for a comprehensive evaluation of published Natura 2000 research to highlight prevalent research themes, disciplinary approaches, and spatial entities. We conducted a systematic review of 572 scientific articles and conference proceedings focused on Natura 2000 research, published between 1996 and 2014. We grouped these articles into ‘ecological’ and ‘social and policy’ categories. Using a novel application of network analysis of article keywords, we found that Natura 2000 research forms a cohesive small-world network, owing to the emphasis on ecological research (79% of studies, with a strong focus on spatial conservation planning), and the underrepresentation of studies addressing ‘social and policy’ issues (typically focused on environmental impact assessment, multi-level governance, agri-environment policy, and ecosystem services valuation). ‘Ecological’ and ‘social and policy’ research shared only general concepts (e.g., Natura 2000, Habitats Directive) suggesting a disconnection between these disciplines. The UK and the Mediterranean basin countries dominated Natura 2000 research, and there was a weak correlation between number of studies and proportion of national territory protected. Approximately 40% of ‘social and policy’ research and 26% of ‘ecological’ studies highlighted negative implications of Natura 2000, while 21% of studies found positive social and biodiversity effects. We emphasize the need for designing inter- and transdisciplinary research in order to promote a social-ecological understanding of Natura 2000, and advance EU conservation policies.

Document type: 
Article
File(s):