Ancient animal migration: a case study of eyeless,dimorphic Devonian trilobites from Poland

We report evidence of one of the oldest known animal migratory episodes in the form of queues of the eyeless trilobite Trimerocephalus chopini Kin & B?a?ejowski, from the Late Devonian (Famennian) of central Poland. In addition, there is evidence for two morphs in this population, one with nine segments and the other with ten. We infer that these queues represent mass migratory chains coordinated by chemotaxis, comparable to those observed in modern crustaceans such as spiny lobsters, and further suggest that the two forms, which occur in an approximately 1:1 ratio, may be dimorphs. These ancient arthropods may have migrated periodically to shallow marine areas for mass mating and spawning. The sudden death of the trilobites in the queues may have been caused by excess carbon dioxide and hydrogen sulphide introduced into the bottom water by distal storm disturbance of anoxic sediments. This study demonstrates the potential for further research on the evolution and ecology of aggregative behaviour in marine arthropods.     

Comparing two methods for estimating floral resource availability for insect pollinators in semi-natural habitats

Pollinator and flowering plant interactions play a critical role in maintaining most terrestrial ecosystems, including agroecosystems. Although estimates of floral resource availability are essential to understand plant–pollinator relationships, no generally accepted methodology exists to date. We compared two methods for sampling floral resources in a single meadow. About every three days, we recorded species lists of insect-pollinated plants with abundance categories assigned to each species (hereafter referred to as scanning) and we counted the flowering shoots in 36 2 × 2 m quadrats (hereafter quadrat sampling). These methods were compared with respect to (i) the number of species detected, (ii) estimated floral resource abundance, and (iii) temporal changes in flowering. With scanning, we found more potential nectar-plant species and species were found earlier than with quadrat sampling. With the latter, abundant species were found with higher probability than the scarce. Flower abundances were correlated between the two methods. We predicted that a cover of 6.3 ± 3.6% should be used for an appropriate estimate of flower abundance in our study site, although the optimal cover probably varies across different habitats. Furthermore, flower abundance changed 6% per day compared to the flowering peak. Overall, scanning seems to be more appropriate for detecting presence and the timing of species, while quadrats may provide higher resolution for abundance estimates. Increased sampling coverage and frequency may enhance research accuracy and using scanning and quadrat sampling simultaneously may help to optimize research effort. We encourage further development of sampling protocols.     

Blood Parasite Infection Intensity Covaries with Risk‐Taking Personality in Male Carpetan Rock Lizards (Iberolacerta cyreni)

Identifying evolutionary and developmental mechanisms underlying consistent between‐individual differences in behaviour is the main goal in ‘animal personality studies’. Here, we explored whether activity and risk‐taking varied consistently between individuals and correlated to various – potentially fitness linked – male traits in Carpetan rock lizards (Iberolacerta cyreni). Lizards showed significant consistency within both behaviours, implying the presence of activity and risk‐taking personalities. However, there were no correlation between activity and risk‐taking, neither on the between‐ nor on the within‐individual levels, implying the absence of a behavioural syndrome. We found a strong link between the intensity of blood parasite (Haemogregarinidae) infection and risk‐taking: lizards with higher infection intensity took more risk. While we cannot distinguish cause from causative in the parasite intensity – risk‐taking correlation – our results are in line with the asset protection hypothesis predicting that individuals with lower future reproductive value should focus on the current reproductive event and take higher risk.     

The Association Between Personality Traits,Morphological Traits and Alternative Mating Behaviour in Male Endler's Guppies,Poecilia wingei

Alternative mating behaviour, personality traits and morphological characters are predicted to be correlated. Bolder, larger and more colourful males are expected to preferentially court females, while shy, small and drab‐coloured individuals are predicted to sneak copulations. We used males of Endler's guppy, Poecilia wingei, to test this association over a long temporal period (hence including ontogenetic changes) and under two social environments (male‐biased and female‐biased). We found that personality traits (exploration, boldness, activity) of P. wingei males were highly repeatable across long time spans, but they were not correlated (formed no behavioural syndrome). Male age and social environment had no effect on any personality trait, despite their effects on alternative mating behaviour. Young males with higher activity levels were more likely to attempt sneaking. In older fish, there was an association between orange coloration, courtship and boldness, but this was not observed in young males. Our results suggest that alternative mating behaviour is more flexible than personality traits and is independent of them. Non‐colour‐based morphological traits (gonopodium length, body length, caudal straps length, dorsal fin length) were not correlated with any particular mating behaviour.     

Do individual Activity Patterns of Brown Trout (Salmo trutta) alter the Exposure to Parasitic Freshwater Pearl Mussel (Margaritifera margaritifera) Larvae?

The hypothesis that interindividual differences in the activity of brown trout alter the exposure to parasitic freshwater pearl mussel glochidia was tested in a Swedish stream. Wild yearling brown trout (N = 103) were caught, individually tagged for identification and scored for open‐field activity during standardized laboratory tests in June. Fifty gravid freshwater pearl mussels were relocated to the stream, where after the trout were released back into the stream. The fish were recaptured in October (N = 35), checked for glochidia encystment (infested individuals: n = 6) and re‐scored for open‐field activity traits. Swimming velocity during the test was higher in fish infected with glochidia, suggesting that high activity could increase their exposure to glochidia. Potentially, as metabolism rate and ventilation rate typically increase with activity, elevated activity may lead to an increased likelihood of glochidia passing over the gills. This novel finding suggests that glochidia infestation is non‐random and that the behaviour of the host fish can influence the likelihood of glochidia infestation.     

Trophy hunting and perceived risk in closed ecosystems: Flight behaviour of three gregarious African ungulates in a semi‐arid tropical savanna

Although being an important conservation tool in Africa, trophy hunting is known to influence risk perception in wildlife species, thus affecting the behaviour and fitness of most targeted species. We studied the effects of trophy hunting on the flight behaviour of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in two closed ecosystems, Cawston Ranch (hunting area) and Stanley and Livingstone Private Game Reserve (tourist area), western Zimbabwe. Using standardized field procedures, we assessed the flight behavioural responses of the three species in two seasons: non‐hunting (December–March) and hunting (April–November) between March 2013 and November 2014. We tested the effect of habitat, group size, sex, season, start distance and alert distance on flight initiation distance using linear mixed models. Habitat, group size sex and alert distance did not have any effect on flight initiation distance for the three species. The three species were more alert and displayed longer flight initiation distances in the hunting area compared with the tourist area. Flight initiation distances for the three species were higher during the hunting season for the hunting area and low during the non‐hunting season. Flight distances of the three species did not differ between the hunting area and the tourist area. We concluded that trophy hunting increased perceived risk of wild ungulates in closed hunting areas, whereas ungulates in non‐hunting areas are less responsive and somehow habituated to human presence. Management plans should include minimum approach distances by tourists as well as establishing seasonal restrictions on special zones to promote species viability. Research aimed at integrating behavioural responses with physiological aspects of target species should be promoted to ensure that managers are able to deal with the behavioural trade‐offs of trophy hunting at local and regional scale.     

Toxicoproteomics in human health and disease: an update

Introduction: Toxicoproteomics is an emerging area of omics, intended to explore the changes in protein expression and modifications in biological samples exposed to toxicants. The development of techniques that utilize sophisticated instruments in proteomics has facilitated the exploration of a wide-range of protein coverage and assisted the quantitative and qualitative evaluation of protein changes as a result of the toxic effects of toxic substances.

Areas covered: Studies on toxicoproteomics have an immense potential to explore the molecular mechanism of action of a variety of toxic substances through deciphering the proteomic map altered as a result of toxicant exposure. Here, we provide an overview of toxicoproteomic approaches and the current paradigm of toxicoproteomics.

Expert commentary: Research in this area continues to increase our understanding of the role of toxicants in worsening human health and toxicity driven diseases. The progress in toxicoproteomics may realize the development of novel biomarkers, drug targets and personalized medicines by incorporating the advanced proteomic applications in this field.