Short- and long-term evolution in our arms race with cancer: Why the war on cancer is winnable.

Human society is engaged in an arms race against cancer, which pits one evolutionary process-human cultural evolution as we develop novel cancer therapies-against another evolutionary process-the ability of oncogenic selection operating among cancer cells to select for lineages that are resistant to our therapies. Cancer cells have a powerful ability to evolve resistance over the short term, leading to patient relapse following an initial period of apparent treatment efficacy. However, we are the beneficiaries of a fundamental asymmetry in our arms race against cancer: Whereas our cultural evolution is a long-term and continuous process, resistance evolution in cancer cells operates only over the short term and is discontinuous - all resistance adaptations are lost each time a cancer patient dies. Thus, our cultural adaptations are permanent, whereas cancer's genetic adaptations are ephemeral. Consequently, over the long term, there is good reason to expect that we will emerge as the winners in our war against cancer

Explaining Andean Potato Weevils in Relation to Local and Landscape Features: A Facilitated Ecoinformatics Approach

BACKGROUND: Pest impact on an agricultural field is jointly influenced by local and landscape features. Rarely, however, are these features studied together. The present study applies a "facilitated ecoinformatics" approach to jointly screen many local and landscape features of suspected importance to Andean potato weevils (Premnotrypes spp.), the most serious pests of potatoes in the high Andes. METHODOLOGY/PRINCIPAL FINDINGS: We generated a comprehensive list of predictors of weevil damage, including both local and landscape features deemed important by farmers and researchers. To test their importance, we assembled an observational dataset measuring these features across 138 randomly-selected potato fields in Huancavelica, Peru. Data for local features were generated primarily by participating farmers who were trained to maintain records of their management operations. An information theoretic approach to modeling the data resulted in 131,071 models, the best of which explained 40.2-46.4% of the observed variance in infestations. The best model considering both local and landscape features strongly outperformed the best models considering them in isolation. Multi-model inferences confirmed many, but not all of the expected patterns, and suggested gaps in local knowledge for Andean potato weevils. The most important predictors were the field's perimeter-to-area ratio, the number of nearby potato storage units, the amount of potatoes planted in close proximity to the field, and the number of insecticide treatments made early in the season. CONCLUSIONS/SIGNIFICANCE: Results underscored the need to refine the timing of insecticide applications and to explore adjustments in potato hilling as potential control tactics for Andean weevils. We believe our study illustrates the potential of ecoinformatics research to help streamline IPM learning in agricultural learning collaboratives

Crop Pests and Predators Exhibit Inconsistent Responses to Surrounding Landscape Composition

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies

Crop pests and predators exhibit inconsistent responses to surrounding landscape composition

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies

Presence of conspecific females motivates egg cannibalism owing to lower risk of filial cannibalism

A cannibal has to weigh the benefits of the consumption and removal of competing conspecifics against the potential loss of fitness through filial cannibalism. We examined the role of the presence of conspecific females in informing adaptive cannibalism decisions. Females of the hemipteran bug Geocoris pallens express low egg cannibalism when alone but become much more cannibalistic in the presence of conspecific females and do not discriminate between their own eggs and those of other females. Experimentation showed that females that could not commit filial cannibalism exhibited strong egg cannibalism that was not reduced by the presence of conspecific females, whereas females that could commit filial cannibalism were very cannibalistic only in the presence of conspecifics. An experiment also showed that the presence of conspecific females triggered a stronger egg cannibalism response in G. pallens than did a heterospecific egg predator. These results suggest that G. pallens females become cannibalistic in the presence of conspecifics because they interpret conspecific presence primarily as an indication of decreased likelihood of committing filial cannibalism, and less so as an indication of lower expected survival of eggs or future resource competition. Our study highlights the importance of informational cues, in this case the presence of conspecifics, in modulating the expression of cannibalism

Influence of crop field size on pest densities, pesticide use, and crop yield

Increasing diversity on farms can enhance many key ecosystem services to and from agriculture, and natural control of arthropod pests is often presumed to be among them. The expectation that increasing the size of monocultural crop plantings exacerbates the impact of pests is common throughout the agroecological literature. Here, we share five data sets, describing 14 pest species, 5 crops (cotton in California, citrus in California, potatoes in Peru, grapes in Spain, and olives in Spain), and 20,000 field-years of observations, that allow us to quantify the impact of field size on pest densities, pesticide applications, and crop yield.Metadata are included with each data file, explaining the meaning of all variables.Funding provided by: U.S. Department of AgricultureCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000199Award Number: USDA-FACT 2020-67021-32477Data were collected by farmers, farm staff, or private pest control advisors in commercial agriculture (subsistence agriculture for Peru only). Detailed methods on sampling are described in the companion paper ("Testing a tenet of agroecology: do larger field sizes exacerbate insect pest problems?")

Control failures following insecticide applications in commercial agriculture: How often do they occur? A case study of Lygus hesperus control in cotton

Although surveys of pest populations documenting evolved insecticide resistance often suggest abundant potential for insecticide control failures, studies documenting the actual occurrence of such failures in commercial agriculture are rare. If farmers currently practice adaptive management, abandoning the use of insecticides once resistance emerges, actual control failures could be rare. Here I use data gathered by independent pest management consultants to describe a case study of the realized efficacy of commercial field applications of insecticides, examining the control of Lygus hesperus (Hemiptera: Miridae) on cotton. On average, insecticides reduced target pest populations to 19% of their pre-application densities. Short-term efficacy of insecticides was variable, but only one severe control failure was observed (1 of 50, 2%). The rarity of severe control failures observed in this study is in agreement with the few other studies conducted in commercial settings, but additional research is needed to assess the generality of this result. Although pesticides can cause longer-term problems, including target pest resurgences and secondary pest outbreaks, risk-averse attitudes among farmers coupled with relatively consistent short-term insecticide efficacy may be potent forces propelling farmers towards the use of insecticides. Here I present data gathered by independent pest management consultants that were used to calculate the realized efficacy of commercial field applications of insecticides, examining the control of Lygus hesperus on cotton. There are no legal or ethical considerations surrounding reuse of these data. The associated metadata file provides explanations for each of the columns of data. Notably, I include both the individual, raw sweep sample counts as well as the mean density estimates that were obtained by averaging across those sweep samples. Location: San Joaquin Valley, California, United States of America.The metadata explaining each column in the dataset is attached to the main data file as a second sheet (see tab at the bottom of the spreadsheet). Funding provided by: U.S. Department of AgricultureCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000199Award Number: 2015-70006-24164: NIFAThese data were collected by an independent pest management consultant and the summer field scouts that he hired to sample populations of Lygus hesperus in commercial cotton fields being grown in the San Joaquin Valley of California. Sampling was performed with a sweep net. I have not processed the data beyond computing means and associated confidence intervals

Evaluating the quality of ecoinformatics data derived from commercial agriculture: a repeatability analysis of pest density estimates

Each year, consultants and field scouts working in commercial agriculture undertake a massive, decentralized data collection effort as they monitor insect populations to make real-time pest management decisions. These data, if integrated into a database, offer rich opportunities for applying big data or ecoinformatics methods in agricultural entomology research. However, questions have been raised about whether or not the underlying quality of these data is sufficiently high to be a foundation for robust research. Here I suggest that repeatability analysis can be used to quantify the quality of data collected from commercial field scouting, without requiring any additional data gathering by researchers. In this context, repeatability quantifies the proportion of total variance across all insect density estimates that is explained by differences across populations and is thus a measure of the underlying reliability of observations. Repeatability was moderately high for cotton fields scouted commercially for total Lygus hesperus Knight densities (R = 0.631) and further improved by accounting for observer effects (R = 0.697). Repeatabilities appeared to be somewhat lower than those computed for a comparable, but much smaller, researcher-generated data set. In general, the much larger sizes of ecoinformatics data sets are likely to more than compensate for modest reductions in measurement precision. Tools for evaluating data quality are important for building confidence in the growing applications of ecoinformatics methods. Here I report the raw data that support these analyses in two files, one reporting the data gathered by the commercial pest control consultant and his summer field scouts and the second gathered by a team or university researchers.Metadata pages included with each data file give simple explanations for each variable. The number of sweep samples made per field varies; thus, there are many NA values for fields that received fewer than the maximum number of sweep samples. Funding provided by: U.S. Department of AgricultureCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000199Award Number: 2015-70006-24164All the data were gathered using sweep sampling in commercial cotton fields. A single sample is gathered by swinging the insect net 50 times across the top of the plant canopy and then counting the number of nymphal and adult Lygus spp. captured