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The San Diego Biodiversity Project introduces undergraduate students at four different 2- and 4-year schools to a short-term research experience (SRE) that was implemented as a module in the last third of a traditional laboratory course. The study assesses the qualities of this SRE for students using three different methods. Twenty-one participants were interviewed about their experiences in the traditional and research components of their course. In a repeated-measures design, 124 participants took the Persistence in the Sciences (PITS) survey immediately before and after their participation in the SRE. Finally, using a propensity score matching technique, PITS survey results for SRE students were compared with those for students in a course-based research experience (CRE). Student perceptions of the traditional lab and the SRE are different-students appreciate learning basic processes and procedures in the traditional lab, but they express having personal investment in and a sense of participating in science in the SRE. Significant increases were found for the variable of Project Ownership in the SRE condition over the traditional lab, but SRE outcomes were lower than CRE outcomes. Although the SRE may not provide the benefits of a CRE, it is a serious option for expanding access to authentic research.

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Despite 250 years of modern taxonomy, there remains a large biodiversity knowledge gap. Most species remain unknown to science. DNA barcoding can help address this gap and has been used in a variety of educational contexts to incorporate original research into school curricula and informal education programmes. A growing body of evidence suggests that actively conducting research increases student engagement and retention in science. We describe case studies in five different educational settings in Canada and the USA: a programme for primary and secondary school students (ages 5-18), a year-long professional development programme for secondary school teachers, projects embedding this research into courses in a post-secondary 2-year institution and a degree-granting university, and a citizen science project. We argue that these projects are successful because the scientific content is authentic and compelling, DNA barcoding is conceptually and technically straightforward, the workflow is adaptable to a variety of situations, and online tools exist that allow participants to contribute high-quality data to the international research effort. Evidence of success includes the broad adoption of these programmes and assessment results demonstrating that participants are gaining both knowledge and confidence. There are exciting opportunities for coordination among educational projects in the future.This article is part of the themed issue 'From DNA barcodes to biomes'.

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It has long been assumed that inbreeding depression in haplodiploid organisms is low due to their ability to purge genetic load in haploid males. It has been suggested that this low genetic load could facilitate the evolution of inbreeding behaviors driven by local mate competition in hymenopteran parasitoids. I have examined inbreeding depression in haplodiploids in two ways. First I show that an outbreeding haplodiploid wasp Uscana semifumipennis (Hymenoptera: Trichogrammatidae) suffers substantial inbreeding depression. Longevity was 38% shorter, fecundity was 32% lower, and sex ratio was 5% more male for experimentally inbred wasps when compared to outbred controls. There were interactions between size and both fecundity and sex ratio for inbred wasps that were not seen for outbred individuals. Second, an analysis of data from the literature suggests that when inbreeding is experimentally imposed on populations, haplodiploid insects and mites as a group do suffer less from inbreeding depression than diploid insects, although substantial inbreeding depression in haplodiploid taxa does exist. The meta-analysis revealed no difference in inbreeding depression between gregarious haplodiploid wasps, which are likely to have a history of inbreeding, and solitary haplodiploid species, which are assumed to be primarily outbred.

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Much of the study of coevolution has focused on the adaptations that have resulted from interactions between species. For reciprocal evolution to occur, there must be genetic variation in each species for traits that directly affect their interaction. Here I report evidence of significant additive genetic variance within a population of parasitic wasps in the ability to successfully parasitize an aphid host. These data, combined with companion work documenting clonal variation in a population of aphids from the same site, provide evidence that within the same population both a host and its parasitoid have the potential for specific and reciprocal genetic interactions.

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For coevolution to occur, there must be genetic variation in each species for traits relevant to their interaction. Here, statistically significant variation in susceptibility to a parasitic wasp was found among pea-aphid clones collected from a single population. In a subset of clones that was tested further, wasps were found to oviposit in aphids from both resistant and susceptible lines, but eggs failed to develop in resistant hosts. Significant genetic variance in susceptibility provides evidence that this aphid population has the potential to evolve resistance in response to selection by one of its major natural enemies. Predictions of an expected response to selection based on the experimental measures of variation and field parasitism rates suggested that there should be a detectable change in susceptibility over the course of a season. However, an experimental comparison of mean susceptibility of clones collected early and late in the summer, a period of several generations, revealed no response to selection by the wasps. Aphids collected late in the season were as susceptible, on the average, as those collected early in the summer. Possible constraints on the response of the aphids to selection by this natural enemy are considered.