Trevon Fuller

The ecology of emerging infectious diseases in migratory birds: an assessment of the role of climate change and priorities for future research.

Pathogens that are maintained by wild birds occasionally jump to human hosts, causing considerable loss of life and disruption to global commerce. Preliminary evidence suggests that climate change and human movements and commerce may have played a role in recent range expansions of avian pathogens. Since the magnitude of climate change in the coming decades is predicted to exceed climatic changes in the recent past, there is an urgent need to determine the extent to which climate change may drive the spread of disease by avian migrants. In this review, we recommend actions intended to mitigate the impact of emergent pathogens of migratory birds on biodiversity and public health. Increased surveillance that builds upon existing bird banding networks is required to conclusively establish a link between climate and avian pathogens and to prevent pathogens with migratory bird reservoirs from spilling over to humans.

Mapping evolutionary process: a multi‐taxa approach to conservation prioritization

Human‐induced land use changes are causing extensive habitat fragmentation. As a result, many species are not able to shift their ranges in response to climate change and will likely need to adapt in situ to changing climate conditions. Consequently, a prudent strategy to maintain the ability of populations to adapt is to focus conservation efforts on areas where levels of intraspecific variation are high. By doing so, the potential for an evolutionary response to environmental change is maximized. Here, we use modeling approaches in conjunction with environmental variables to model species distributions and patterns of genetic and morphological variation in seven Ecuadorian amphibian, bird, and mammal species. We then used reserve selection software to prioritize areas for conservation based on intraspecific variation or species‐level diversity. Reserves selected using species richness and complementarity showed little overlap with those based on genetic and morphological variation. Priority areas for intraspecific variation were mainly located along the slopes of the Andes and were largely concordant among species, but were not well represented in existing reserves. Our results imply that in order to maximize representation of intraspecific variation in reserves, genetic and morphological variation should be included in conservation prioritization.

Influence of Representation Targets on the Total Area of Conservation‐Area Networks

Systematic conservation planning typically requires specification of quantitative representation targets for biodiversity surrogates such as species, vegetation types, and environmental parameters. Targets are usually specified either as the minimum total area in a conservation-area network in which a surrogate must be present or as the proportion of a surrogates existing spatial distribution required to be in the network. Because the biological basis for setting targets is often unclear, a better understanding of how targets affect selection of conservation areas is needed. We studied how the total area of conservation-area networks depends on percentage targets ranging from 5% to 95%. We analyzed 12 data sets of different surrogate distributions from 5 regions: Korea, Mexico, Québec, Queensland, and West Virginia. To assess the effect of spatial resolution on the target-area relationship, we also analyzed each data set at 7 spatial resolutions ranging from 0.01 degrees x 0.01 degrees to 0.10 degrees x 0.10 degrees. Most of the data sets showed a linear relationship between representation targets and total area of conservation-area networks that was invariant across changes in spatial resolution. The slope of this relationship indicated how total area increased with target level, and our results suggest that greater surrogate representation requires significantly more area. One data set exhibited a highly nonlinear relationship. The results for this data set suggest a new method for setting targets on the basis of the functional form of target-area relationships. In particular, the method shows how the target-area relationship can provide a rationale for setting targets solely on the basis of distributional information about surrogates.

Predicting Hotspots for Influenza Virus Reassortment

TOC summary: Reassortment is most likely to occur in eastern China, central China, or the Nile Delta in Egypt.

Mapping the risk of avian influenza in wild birds in the US

BackgroundAvian influenza virus (AIV) is an important public health issue because pandemic influenza viruses in people have contained genes from viruses that infect birds. The H5 and H7 AIV subtypes have periodically mutated from low pathogenicity to high pathogenicity form. Analysis of the geographic distribution of AIV can identify areas where reassortment events might occur and how high pathogenicity influenza might travel if it enters wild bird populations in the US. Modelling the number of AIV cases is important because the rate of co-infection with multiple AIV subtypes increases with the number of cases and co-infection is the source of reassortment events that give rise to new strains of influenza, which occurred before the 1968 pandemic. Aquatic birds in the orders Anseriformes and Charadriiformes have been recognized as reservoirs of AIV since the 1970s. However, little is known about influenza prevalence in terrestrial birds in the order Passeriformes. Since passerines share the same habitat as poultry, they may be more effective transmitters of the disease to humans than aquatic birds. We analyze 152 passerine species including the American Robin (Turdus migratorius) and Swainsons Thrush (Catharus ustulatus).MethodsWe formulate a regression model to predict AIV cases throughout the US at the county scale as a function of 12 environmental variables, sampling effort, and proximity to other counties with influenza outbreaks. Our analysis did not distinguish between types of influenza, including low or highly pathogenic forms.ResultsAnalysis of 13,046 cloacal samples collected from 225 bird species in 41 US states between 2005 and 2008 indicates that the average prevalence of influenza in passerines is greater than the prevalence in eight other avian orders. Our regression model identifies the Great Plains and the Pacific Northwest as high-risk areas for AIV. Highly significant predictors of AIV include the amount of harvested cropland and the first day of the year when a county is snow free.ConclusionsAlthough the prevalence of influenza in waterfowl has long been appreciated, we show that 22 species of song birds and perching birds (order Passeriformes) are influenza reservoirs in the contiguous US.

Short Communication: LQGraph: A software package for optimizing connectivity in conservation planning

LQGraph implements methods for optimizing the connectivity of sites administered to protect biodiversity (a conservation area network). The methods are suitable for existing protected areas (for example, national parks) or a proposed network. We model the landscape using graphs. The user provides a quality score for each site in the landscape outside the conservation areas. Based on these scores, LQGraph finds contiguity areas of maximum quality to link the conservation areas. The contiguity areas can be filtered to prioritize those that connect the conservation areas with the minimum number of sites or area. Compared with existing methods for establishing connectivity in a conservation area network, LQGraph can analyze substantially larger networks. LQGraph also identifies sites that efficiently isolate conservation areas, which is useful for halting the spread of pathogens or invasive species. The software provides routines for constructing the required input files and for visualizing several properties of the landscape, including site quality and the shortest paths between conservation areas. LQGraph and the accompanying documentation can be freely downloaded from the worldwide web.

The use of norms of reaction to analyze genotypic and environmental influences on behavior in mice and rats

Norms of reaction (NoRs) represent the phenotypic values of genotypes as functions of environmental parameters and permit the visualization of differences in phenotypic response of different genotypes. NoR graphs can be used to analyze interactions between genotypic and environmental factors during development to produce phenotypes in inbred strains of rats and mice. We describe the main features of NoRs, the history of their use in this context, and discuss several applications in behavioral neuroscience. In addition, we give a test for determining whether distinct strains have different NoRs.

Systematic conservation assessment for the Mesoamerica, Chocó, and Tropical Andes biodiversity hotspots: a preliminary analysis

Using IUCN Red List species as biodiversity surrogates, supplemented with additional analyses based on ecoregional diversity, priority areas for conservation in Mesoamerica, Chocó, and the Tropical Andes were identified using the methods of systematic conservation planning. Species’ ecological niches were modeled from occurrence records using a maximum entropy algorithm. Niche models for 78 species were refined to produce geographical distributions. Areas were prioritized for conservation attention using a complementarity-based algorithm implemented in the ResNet software package. Targets of representation for Red List species were explored from 10 to 90% of the modeled distributions at 10% increments; for the 53 ecoregions, the target was 10% for each ecoregion. Selected areas were widely dispersed across the region, reflecting the widespread distribution of Red List species in Mesoamerica, Chocó, and the Tropical Andes, which underscores the region’s importance for biodiversity. In general, existing protected areas were no more representative of biodiversity than areas outside them. Among the countries in the region, the protected areas of Belize performed best and those of Colombia and Ecuador worst. A high representation target led to the selection of a very large proportion of each country except Colombia and Ecuador (for a 90% target, 83–95% of each country was selected). Since such large proportions of land cannot realistically be set aside as parks or reserves, biodiversity conservation in Mesoamerica, Chocó, and the Tropical Andes will require integrative landscape management which combines human use of the land with securing the persistence of biota.

Postnatal environment affects behavior of adult transgenic mice.

Behavioral phenotypes of knockout mice are often interpreted as the effects of the absence of the gene product on adult behavior, yet behavioral differences among genotypes may be exaggerated or blurred by the postnatal environment. For example, mice develop in litters of varying sex ratios and genotypes, and it is possible that some of these behavioral differences may result from the composition of the litter. To determine whether these factors might play a role in the development of the behavioral characteristics that have become diagnostic of the knockout, offspring of parents heterozygous for a null mutation of estrogen receptor α (ERKO) were sexed and genotyped within 2 days of birth. Litters were then reconstituted, forming same-sex litters of equal numbers of ERKO and wild-type (WT) individuals that were tested in a standard resident-intruder paradigm. In this manner the effect of genotype would be evident without the potential confound of the presence of the opposite sex in the litter. Behavioral differences between the genotypes were more sharply defined than reported previously. ERKO females displayed only aggressive behavior whereas their WT littermates displayed only mounting behavior; both aggression and mounting behavior were greatly reduced in ERKO males. These data suggest that the postnatal environment such as litter composition may influence the development of sociosexual behaviors in ERKO mice.

Generalized norms of reaction for ecological developmental biology.

SUMMARY A standard norm of reaction (NoR) is a graphical depiction of the phenotypic value of some trait of an individual genotype in a population as a function an environmental parameter. NoRs thus depict the phenotypic plasticity of a trait. The topological properties of NoRs for sets of different genotypes can be used to infer the presence of (nonlinear) genotype–environment interactions. Although it is clear that many NoRs are adaptive, it is not yet settled whether their evolutionary etiology should be explained by selection on the mean phenotypic trait values in different environments or whether there are specific genes conferring plasticity. If the second alternative is true, the NoR is itself an object of selection. Generalized NoRs depict plasticity at the level of populations or subspecies within a species, species within a genus, or taxa at higher levels. Historically, generalized NoRs have routinely been drawn though rarely explicitly recognized as such. Such generalized NoRs can be used to make evolutionary inferences at higher taxonomic levels in a way analogous to how standard NoRs are used for microevolutionary inferences.