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The family Alaudidae, larks, comprises 93–100 species (depending on taxonomy) that are widely distributed across Africa and Eurasia, with single species extending their ranges to North and northernmost South America and Australia. A decade-old molecular phylogeny, comprising ∼80% of the species, revealed multiple cases of parallel evolution and large variation in rates of morphological evolution, which had misled taxonomists into creating many non-monophyletic genera. Here, we reconstruct the phylogeny of the larks, using a dataset covering one mitochondrial and 16 nuclear loci and comprising all except one of the currently recognised species as well as several recently proposed new species (in total 133 taxa; not all loci available for all species). We provide additional support using genome-wide markers to infer a genus-level phylogeny based on near-complete generic sampling (in total 51 samples of 44 taxa across 40 species). Our results confirm the previous findings of rampant morphological convergence and divergence, and reveal new cases of paraphyletic genera. We propose a new subfamily classification, and also that the genus Mirafra is divided into four genera to produce a more balanced generic classification of the Alaudidae. Our study supports recently proposed species splits as well as some recent lumps, while also questioning some of the latter. This comprehensive phylogeny will form an important basis for future studies, such as comparative studies of lark natural history, ecology, evolution and conservation.

The species complex comprising the rufous-naped lark Corypha africana, Sharpe’s lark Corypha sharpii, the red-winged lark Corypha hypermetra, the Somali long-billed lark Corypha somalica and Ash’s lark Corypha ashi encompasses 31 recognised taxa across sub-Saharan Africa, many of which are extremely poorly known and some not observed for decades. Only 17 taxa have been studied molecularly and none comprehensively for morphology, vocalisations or other behaviours. Here, we undertake comprehensive integrative taxonomic analyses based on plumage and morphometrics (for 97% of the taxa), mitochondrial and nuclear loci (77%), ≤ 1.3 million genome-wide single nucleotide polymorphisms (68%), song (many described for the first time; 52%) and additional behavioural data (45%). All polytypic species as presently circumscribed are paraphyletic, with eight primary clades separated by ≤ 6.3–6.8 Myr, broadly supported by plumage, morphometrics, song and other behaviours. The most recent divergences concern sympatric taxon pairs usually treated as separate species, whereas the divergence of all clades including C. africana subspecies is as old as sister species pairs in other lark genera. We propose the recognition of nine instead of five species, while C. ashi is synonymised with C. somalica rochei as C. s. ashi. The geographical distributions are incompletely known, and although the nine species are generally para-/allopatric, some might be sympatric.

Migration has fascinated researchers for years and many active areas of study exist. However, the question of how migratory species stay healthy within the context of their annual cycle remains relatively unexplored. This article addresses this question using Red Knots (Calidris canutus) as a model migrant species. We review recent research on immune function in Red Knots and integrate this work with the broader eco-immunological literature to introduce a conceptual model. This model synthesizes earlier ideas about resource allocation and the costs of immunity with recent increases in our knowledge about the vertebrate immune system and then puts these concepts into the context of defense against real pathogens in environments where a myriad of factors change in time and space. We also suggest avenues for further research, which will help to test the model and better link measures of immune function to pressure from pathogens and to optimal defense against disease.

Ecological immunologists are interested in how immune function changes during different seasons and under different environmental conditions. However, an obstacle to answering such questions is discerning the effects of biological factors of interest and investigation artifacts such as handling stress. Here we examined handling stress and its effects on constitutive (noninduced) immune function via two protocols on captive red knots (Calidris canutus). We investigated how constitutive immunity responds to handling stress, how quickly these changes take place, and the practical implications for researchers interested in sampling baseline immune levels. We found that Staphylococcus aureus and Candida albicans killing increased with handling stress while total leukocyte and lymphocyte concentrations decreased. However, although corticosterone increased significantly and rapidly in response to handling stress, none of the 10 measures of constitutive immunity that we tested differed significantly from baseline withinn20 or 30 min of capture. Thus, researchers interested in baseline immune function should sample animals as soon as possible after capture, but studies in species not easily sampled in less than 3 min (such as red knots) could still yield useful results.