The ratite moa (Aves; Dinornithiformes) were massive graviportal browsers weighing up to 250 kg (ref. 1) that dominated the New Zealand biota until their extinction approximately 500 yr ago. Despite an extensive Quaternary fossil record, moa taxonomy remains problematic and currently 11 species are recognized. Three Dinornis species were found throughout New Zealand and differed markedly in size (1-2 m height at back) and mass (from approximately 34 to 242 kg). Surprisingly, ancient mitochondrial DNA sequences show that the three species were genetically indistinguishable within each island, but formed separate North and South Island clades. Here we show, using the first sex-linked nuclear sequences from an extinct species, that on each island the three morphological forms actually represent just one species, whose size varied markedly according to sex and habitat. The largest females in this example of extreme reversed sexual size dimorphism were about 280% the weight and 150% the height of the largest males, which is unprecedented among birds and terrestrial mammals. The combination of molecular and palaeontological data highlights the difficulties of analysing extinct groups, even those with detailed fossil records.

RTS,S/AS01E has been tested in a phase 3 malaria vaccine study with partial efficacy in African children and infants. In a cohort of 1028 subjects from one low (Bagomoyo) and two high (Nanoro, Kintampo) malaria transmission sites, we analysed IgG plasma/serum concentration and avidity to CSP (NANP-repeat and C-terminal domains) after a 3-dose vaccination against time to clinical malaria events during 12-months. Here we report that RTS,S/AS01E induces substantial increases in IgG levels from pre- to post-vaccination ( p < 0.001), higher in NANP than C-terminus (2855 vs 1297 proportional change between means), and higher concentrations and avidities in children than infants ( p < 0.001). Baseline CSP IgG levels are elevated in malaria cases than controls ( p < 0.001). Both, IgG magnitude to NANP (hazard ratio [95% confidence interval] 0.61 [0.48–0.76]) and avidity to C-terminus (0.07 [0.05–0.90]) post-vaccination are significantly associated with vaccine efficacy. IgG avidity to the C-terminus emerges as a significant contributor to RTS,S/AS01E-mediated protection.

For modern lineages of birds and mammals, few fossils have been found that predate the Cretaceous–Palaeogene (K–Pg) boundary. However, molecular studies using fossil calibrations have shown that many of these lineages existed at that time. Both birds and mammals are parasitized by obligate ectoparasitic lice (Insecta: Phthiraptera), which have shared a long coevolutionary history with their hosts. Evaluating whether many lineages of lice passed through the K–Pg boundary would provide insight into the radiation of their hosts. Using molecular dating techniques, we demonstrate that the major louse suborders began to radiate before the K–Pg boundary. These data lend support to a Cretaceous diversification of many modern bird and mammal lineages.

Giant kelp Macrocystis pyrifera is a foundational species that forms a 3-dimensional habitat and supports numerous high-value fisheries species. Constant grazing of kelp holdfasts by overabundant sea urchins causes catastrophic ecological and economic impacts on rocky reefs worldwide. Overgrazing creates urchin barrens that persist for decades in the absence of ecological forcing that would shift the ecosystem back to a kelp-dominated state. Annual surveys of kelp forest and urchin barren sites in the Southern California Bight were performed from 2011 to 2020 to assess changes in kelp forest communities as a result of restoration efforts through sea urchin culling. However, that time period also encompassed a sea urchin mass mortality event. Following drastic reductions of sea urchin densities, rocky reefs returned to a kelp-dominated state within approximately 6 mo and remained stable through the remainder of the study. Benthic cover, fish, and kelp and macroinvertebrate communities inside former urchin barrens became more similar to that of kelp forest reference sites and continued to do so for the next 5 yr. Giant kelp density increased significantly compared to existing kelp forests, while benthic indicators of urchin dominance (i.e. crustose coralline algae and bare rock cover) decreased. Kelp restoration through sea urchin culling essentially mimics sea urchin mass mortality events. If culling can produce similar declines in urchin density, it may be a viable management tool to rapidly restore persistent urchin barrens at moderate spatial scales, while a mass mortality event can drive recovery of kelp forest communities at more extensive spatial scales.

Bovine tuberculosis (bTB) is one of the globe’s most common, multihost zoonoses and results in substantial socioeconomic costs for governments, farming industries, and tax payers. Despite decades of surveillance and research, surprisingly, little is known about the exact mechanisms of transmission. In particular, as a facultative intracellular pathogen, to what extent does survival of the causative agent, Mycobacterium tuberculosis var. bovis (M. bovis), in the environment constitute an epidemiological risk for livestock and wildlife? Due largely to the classical pathology of cattle cases, the received wisdom was that bTB was spread by direct inhalation and exchange of bioaerosols containing droplets laden with bacteria. Other members of the Mycobacterium tuberculosis complex (MTBC) exhibit differing host ranges, an apparent capacity to persist in environmental fomites, and they favour a range of different transmission routes. It is possible, therefore, that infection from environmental sources of M. bovis could be a disease transmission risk. Recent evidence from GPS-collared cattle and badgers in Britain and Ireland suggests that direct transmission by infectious droplets or aerosols may not be the main mechanism for interspecies transmission, raising the possibility of indirect transmission involving a contaminated, shared environment. The possibility that classical pulmonary TB can be simulated and recapitulated in laboratory animal models by ingestion of contaminated feed is a further intriguing indication of potential environmental risk. Livestock and wildlife are known to shed M. bovis onto pasture, soil, feedstuffs, water, and other fomites; field and laboratory studies have indicated that persistence is possible, but variable, under differing environmental conditions. Given the potential infection risk, it is timely to review the available evidence, experimental approaches, and methodologies that could be deployed to address this potential blind spot and control point. Although we focus on evidence from Western Europe, the concepts are widely applicable to other multihost bTB episystems.

Ex vivo functional immunoassays such as ELISpot and intracellular cytokine staining (ICS) by flow cytometry are crucial tools in vaccine development both in the identification of novel immunogenic targets and in the immunological assessment of samples from clinical trials. Cryopreservation and subsequent thawing of PBMCs via validated processes has become a mainstay of clinical trials due to processing restrictions inherent in the disparate location and capacity of trial centres, and also in the need to standardize biological assays at central testing facilities. Logistical and financial requirement to batch process samples from multiple study timepoints are also key. We used ELISpot and ICS assays to assess antigen-specific immunogenicity in blood samples taken from subjects enrolled in a phase II malaria heterologous prime-boost vaccine trial and showed that the freeze thaw process can result in a 3–5-fold reduction of malaria antigen-specific IFNγ-producing CD3+CD4+ effector populations from PBMC samples taken post vaccination. We have also demonstrated that peptide responsive CD8+ T cells are relatively unaffected, as well as CD4+ T cell populations that do not produce IFNγ. These findings contribute to a growing body of data that could be consolidated and synthesised as guidelines for clinical trials with the aim of increasing the efficiency of vaccine development pipelines.

Abstract. When taking an ecosystem-based approach to marine resource management, managers may be able to implement a combination of management tools in order to mitigate the socioeconomic impacts of implementing any one in isolation, while providing greater overall ecological benefits. The harvest of Strongylocentrotus franciscanus (red sea urchin) for their gonads is one of the most important commercial fisheries in California. However, in some locations, high densities of the unfished Strongylocentrotus purpuratus (purple sea urchin) can clear expanses of kelp forest resulting in ''urchin barrens.'' The lack of macroalgal food resources can result in reduced gonad production, making S. franciscanus within barrens less valuable to a fishery. We investigated the potential of kelp forest habitat restoration, which may be achievable primarily by removing S. purpuratus from barrens, to positively impact the local S. franciscanus fishery and offset the losses in fishing grounds within recently established MPAs in our study area. Generalized linear modeling of the relationship between gonad weight and length (test diameter) demonstrated clear size-specific differences in gonad production between urchins collected in barrens and kelp forests. These relationships varied over time, with the maximum observed mean gonad biomass at length being 484% greater in kelp forest than barren habitat for S. franciscanus just above the legal size limit. The variability in S. franciscanus density (5.2 times greater in urchin barrens), size structure (mean test diameters were approximately 50% greater in kelp forest) and gonad production were then incorporated using Monte Carlo simulations. Results indicated that restoration could potentially result in an 864% increase in S. franciscanus gonad biomass available to the fishery, and a 132% increase in reproductive potential per unit area of urchin barren restored to kelp forest. If all 36 ha of urchin barren habitat mapped outside of the new MPAs in the study area were restored, the increase in gonad biomass available to the fishery could potentially offset 52% of which is now protected within the 109 ha of rocky reef in the new MPAs. Kelp restoration has the potential to play a valuable role as one of many integrated tools in an ecosystem-based management approach.

Adaptive immune responses are initiated by resident myeloid tissue DC. A major fraction of tissue DC express CD1c and is thought to be derived from blood CD1c DC, an idea supported here by the observation that they express tissue-homing molecules and rapidly differentiate into cells with a tissue DC phenotype. Responses are thought to be augmented/modulated further by inflammatory moDC. Although much accepted human myeloid DC cell biology is based on moDC studies, we find these 2 DC populations to be functionally distinct. Stimulated moDC produce high levels of IL-10 and the Th1-promoting cytokine IL-12. Under identical conditions, CD1c DC synthesized no IL-10 and no or low levels of IL-12. Despite this, CD1c DC stimulated a strong Th1 response, demonstrated by IL-12 neutralization to be IL-12 independent, whereas the response induced by moDC was IL-12 dependent. This finding was supported by studies on a patient with a highly reduced ability to synthesize IL-12, whose CD1c DC induced a good Th1 response contrasting with the failure of his moDC, which were impaired in IL-12 production, to induce IFN--secreting T cells. The IL-10 and IL-12 data were confirmed by microarray analysis, which also showed that stimulated moDC produced inflammatory-associated chemokines and cytokines, whereas stimulated CD1c DC showed minimal up-regulation of these genes. Thus, moDC, widely used as a human myeloid DC model, do not faithfully reflect the properties of CD1c tissue DC, making the initial response to a pathogen or vaccine.