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Nest site availability plays an important role in the ecology of the birds inhabiting intensive agricultural landscapes. The removal of trees and snags due to logging is one of the main threats and the cause of the observed decline in many birds living in an agricultural landscape. When nests are lost, nesting passerines typically rebuild them for a new clutch. Additionally, relocating nests after a brood loss is a prevalent strategy used to avoid predators and brood parasites. Such a strategy is common to the Red-backed Shrike, which builds successive nests for each brood. Interestingly, clutch replacement may occur in unusual forms. This study describe three cases of Song Thrush nests reused by Red-backed Shrikes during one breeding season. The time and energy-saving behaviour or possible deterrence of nest parasitism could explain why the nests have been reused. However, due to the limited observations as compared to the total number of nests, further research is necessary to clarify this phenomenon.

Medical ultrasound images are reconstructed with simplifying assumptions on wave propagation, with one of the most prominent assumptions being that the imaging medium is composed of a constant sound speed. When the assumption of a constant sound speed are violated, which is true in most in vivoor clinical imaging scenarios, distortion of the transmitted and received ultrasound wavefronts appear and degrade the image quality. This distortion is known as aberration, and the techniques used to correct for the distortion are known as aberration correction techniques. Several models have been proposed to understand and correct for aberration. In this review paper, aberration and aberration correction are explored from the early models and correction techniques, including the near-field phase screen model and its associated correction techniques such as nearest-neighbor cross-correlation, to more recent models and correction techniques that incorporate spatially varying aberration and diffractive effects, such as models and techniques that rely on the estimation of the sound speed distribution in the imaging medium. In addition to historical models, future directions of ultrasound aberration correction are proposed.

Abstract Daylight is an important factor necessary for the proper embryonic development of birds, which raises the question, what happens when birds nest in relatively dim sites? The study experimentally tested whether there is a relationship between light conditions at the nesting site and the protoporphyrin-based pigmentation in the eggshell of the Great Tit (Parus major). We hypothesised that at lower light levels, eggs are less pigmented to increase the amount of light reaching the embryo. Our study system consisted of two types of nest boxes: "dark", in which the only source of light was the entrance hole, and "bright", which had two additional side windows. Photographs of clutches taken during the incubation period were used to quantify eggshell pigmentation. Multispectral image analyses were performed to measure variables correlating with protoporphyrin content, such as spot brightness, average spot size, spotting coverage, and spot red chroma. Repeatability analysis indicated that eggshell colouration characteristics were significantly and moderately repeatable between eggs from a single clutch, which suggests that they are under genetic and environmental control. However, none of the pigmentation traits differed significantly between the two types of nest boxes. We speculate about other ecological aspects that might have influenced the observed variability in eggshell pigmentation.

Brood overlapping is a breeding strategy that aims at shortening the time between successive broods. Most typically, each brood is raised in separate nest and parents share care between broods. If successive overlapping broods are located in the same nest, the second brood is usually initiated after nestlings from the previous brood have left the nest. The cases in which a female lays eggs in the same nest but before the nestlings from the previous brood have fledged (hereafter, Single Nest Brood Overlapping, SNBO) are rare and seldom studied. Based on a literature research, we revise data on SNBO occurrence. To date, about 37 cases of SNBO have been recorded in eight bird species and occurs mainly nest box breeders. Moreover, we surveyed SNBO in a wild-living passerine, Great Tit (Parus major). We found evidence of SNBO in 10.1% of the 69 first broods that we monitored using camera traps installed inside nest boxes. Females started the second brood when first brood nestlings were 17–19 days old, up to 6 days prior to fledging. This type of brood overlap occurred more often in nests that had smaller initial number of fledglings. The timing of the first brood, the clutch size and duration of the nestling phase had no significant effect on SNBO occurrence. We discuss some potential causes and fitness consequences of this unusual breeding strategy.

Abstract Despite the relevance of chemical communication in vertebrates, comparative examinations of macroevolutionary trends in chemical signaling systems are scarce. Many turtle and tortoise species are reliant on chemical signals to communicate in aquatic and terrestrial macrohabitats, and many of these species possess specialized integumentary organs, termed mental glands (MGs), involved in the production of chemosignals. We inferred the evolutionary history of MGs and tested the impact of macrohabitat on their evolution. Inference of ancestral states along a time-calibrated phylogeny revealed a single origin in the ancestor of the subclade Testudinoidea. Thus, MGs represent homologous structures in all descending lineages. We also inferred multiple independent losses of MGs in both terrestrial and aquatic clades. Although MGs first appeared in an aquatic turtle (the testudinoid ancestor), macrohabitat seems to have had little effect on MG presence or absence in descendants. Instead, we find clade-specific evolutionary trends, with some clades showing increased gland size and morphological complexity, whereas others exhibiting reduction or MG loss. In sister clades inhabiting similar ecological niches, contrasting patterns (loss vs. maintenance) may occur. We conclude that the multiple losses of MGs in turtle clades have not been influenced by macrohabitat and that other factors have affected MG evolution.

Abstract Artificial boxes are commonly used in studies of cavity‐dwelling animals of various taxa. One advantage of nest boxes is that cameras can be used to monitor animals inside the cavity, however, most cameras used today have to be built de novo or modified or are expensive. Here, we describe a method for monitoring nest boxes using off‐the‐shelf models of trail cameras that can record photographs and videos in daylight and darkness (TCM; Trail Camera Method). The cameras can record sequentially within a given time lapse or an infra‐red motion sensor can be triggered by activity in the nest box. Using TCM in a Great Tit (Parus major) nest box population, we studied the hourly pattern of the first egg laying and the first egg hatching. We found that Great Tits laid eggs within 2 h of the sunrise while the timing of hatching spanned the 24‐h day. Moreover, we found that the hour of hatching affects the nestlings’ mass on the 2nd day of life, but not on the 12th day of life. Comparing to traditional nest box checks, TMC requires about 75% less time to obtain data on the timing of egg laying and hatching. Moreover, the hour estimation error was several orders of magnitude greater with the traditional method. Our data demonstrate that commercially available trail cameras are an affordable and convenient method of monitoring artificial cavities. Trail cameras are small, standalone, weather‐proof devices with integrated powering, memory storage, lighting, and recording systems. They could be easily swapped between boxes or removed. After small modifications of the box, they could be used to monitor a wide variety of behaviors of many animal taxa.

Despite evidence from anatomy, behavior and genomics indicating that the sense of smell in turtles is important, our understanding of chemical communication in this group is still rudimentary. Our aim was to describe the microanatomy of mental glands (MGs) in a freshwater turtle, Mauremys leprosa (Geoemydidae), and to assess the chemical composition of their secretions with respect to variation among individuals and between sexes. MGs are paired sac-like organs on the gular region of the neck and are dimorphic in this species with males having fully functional holocrine glands while those of females appear non-secretory and vestigial. In adult males, the glandular epithelium of the inner portion of the gland provides exocytotic products as well as cellular debris into the lumen of the gland. The contents of the lumen can be secreted through the narrow duct portion of the gland ending in an orifice on the surface of the skin. Females have invaginated structures similar in general outline to male glands, but lack a glandular epithelium. Using gas chromatography coupled to mass spectrometry, we identified a total of 61 compounds in mental gland secretions, the most numerous being carboxylic acids, carbohydrates, alkanes, steroids and alcohols. The number of compounds per individual varied widely (mean (median) ± SD = 14.54 (13) ± 8.44; min = 3; max = 40), but only cholesterol was found in all samples. We found that the relative abundances of only six chemicals were different between the sexes, although males tended to have larger amounts of particular compounds. Although the lipid fraction of mental gland secretions is rich in chemical compounds, most occur in both sexes suggesting that they are metabolic byproducts with no role in chemical signaling. However, the relative amounts of some compounds tended to be higher in males, with significantly larger amounts of two carboxylic acids and one steroid, suggesting their putative involvement in chemical communication.

Ilex paraguariensis (yerba mate) is a plant species of the holly genus Ilex native to South America from the family Aquifoliaceae and is used for the production of yerba mate infusion. The leaves of the plant are steeped in hot water to make a beverage known as mate. The present study aimed to quantify and compare the content of selected elements in dried leaves and stems of I. paraguariensis (originating from Paraguay, Argentina, and Brazil) available in the market in Poland and determine the amount of these elements and bioactive compounds that pass into the infusion prepared from them. The contents of the following antioxidant compounds were assessed: neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, 4-feruloylquinic acid, isochlorogenic acid, rutoside, astragalin, caffeine, and indole derivatives. All the tested samples showed the presence of elements such as magnesium, zinc, copper, iron, and manganese. The highest antioxidant activity was determined for infusion prepared from yerba mate samples from Brazil. Drinking approximately 1 L of the infusion a day will partially cover the daily requirement of these elements and bioactive compounds. The highest content of organic compounds with antioxidant properties (phenolic compounds and caffeine) was found in yerba mate infusions from Brazil.

Introduction Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies among women at reproductive age, but its pathology remains unknown. From epidemiological studies it is known that endogenous, mainly genetic and exogenous, environmental factors are of importance. Objective The aim of the study was to compare the phenotype of women diagnosed with PCOS from urban and rural areas of Poland. According to the knowledge of the authors, this is first such study. Material and Methods The retrospective study included 3,877 PCOS patients: 2511 women living in cities and 1,366 village inhabitants, aged between 18 – 45 years. Clinical data, including medical history, body mass, height and hirsutism severity was obtained from each patient. Hormones were also tested in each patient: follicle stimulating hormone, luteinizing hormone, prolactin, estradiol [E2], testosterone, dehydroepiandrosterone sulphate [DHEAS], thyroid stimulating hormone, free thyroxin, insulin [INS], 17 hydroxyprogesterone, cortisol [CORT]) and metabolic (75g oral glucose tolerance test, Chol – total cholesterol, HDL-C – high density lipoprotein cholesterol, LDL-C low density lipoprotein cholesterol, and the TG (triglicerides) profile. Results PCOS women from urban areas had a higher mean serum concentration of E2 in comparison to the inhabitants of rural areas. Women from cities had a lower mean level of DHEAS, CORT, and INS measured in the morning than rural residents. Insulin-resistance, using homeostasis model assessment, was more pronounced among women from villages. The prevalence of menstrual disorders, in general, was higher in PCOS women living in rural comparing to urban areas. Conclusions The clinical and biochemical indices differed significantly between women diagnosed with PCOS living in cities and villages. In general in Poland, the PCOS phenotype is more severe in women living in rural areas. This study shows that different living conditions significantly affect the PCOS phenotype.

Abstract Light has a significant impact on many aspects of avian biology, physiology and behaviour. An increasing number of studies show that illumination may positively influences birds’ offspring fitness by e.g. acceleration of embryo development, stimulation of skeleton growth or regulation of circadian rhythm. Because nest cavities have especially low illumination, suitable light levels may be especially important for species which nest there. We may therefore expect that birds breeding in relatively dim conditions should prefer brighter nest sites and/or evolve behavioral mechanisms to secure sufficient light levels in the nest. Using nest boxes with modified internal illumination, we experimentally tested whether light regime is a cue for nest site selection of secondary cavity-nesting species. Additionally, we investigated whether nest building strategies are tuned to internal illumination. Our results demonstrate that, nest boxes with elevated illumination were chosen twice as often as dark nest boxes. Moreover, birds built higher nests in dark nest boxes than birds in boxes with elevated illumination, which suggests a mechanism of compensating for low light conditions. Our results provide the first experimental support for the idea that nest site choice and nest building behaviour in cavity-nesting birds are influenced by ambient illumination.