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1.
Proc Biol Sci ; 286(1898): 20190316, 2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30836868

RESUMEN

Evaluating intrinsic and extrinsic traits that predispose species to local extinction is important for targeting conservation efforts. Among the species of special concern in Europe are bees, which, along with butterflies, are the best monitored insects. Bees are most species-rich in Mediterranean-type climates with short winters, warm springs, and dry summers. In Central Europe, climate warming per se is, therefore, expected to benefit most bee species, while pesticides and the loss of habitats and plant diversity should constitute threats. Here, we use the bee fauna of Germany, which has been monitored for Red Lists for over 40 years, to analyse the effects of habitat breadth, pollen specialization, body size, nesting sites, sociality, duration of flight activity, and time of emergence during the season. We tested each factor's predictive power against changes in commonness and Red List status, using phylogenetically informed hierarchical Bayesian (HB) models. Extinction vulnerability is strongly increased in bees flying in late summer, with a statistical model that included flight time, habitat preference, and duration of activity correctly predicting the vulnerability status of 85% of the species. Conversely, spring emergence and occurrence in urban areas each reduce vulnerability, pointing to intensive land use especially harming summer-active bees, with the combination of these factors currently shifting Germany's bee diversity towards warm-adapted, spring-flying, city-dwelling species.


Asunto(s)
Abejas/fisiología , Biodiversidad , Cambio Climático , Ecosistema , Extinción Biológica , Animales , Alemania , Dinámica Poblacional , Estaciones del Año
2.
Int J Legal Med ; 133(1): 3-16, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30032458

RESUMEN

Bloodstains on textiles can provide useful information for the forensic reconstruction of a crime. Surprisingly, little is known about the applicability of bloodstain traces after a textile was machine washed. In this study, we investigated the effect of machine washing on bloodstains on both cotton and polyester cloths. The influence of the washing detergent, the type of washing machine, the washing temperature, and the duration of drying of the bloodstain prior to washing as well as the drying temperature was investigated. Additionally, the molecular analyses of a subsample of the experiments were conducted. We found that although the primary morphology of the traces is often blurred, the presence of blood on the textiles can still be detected in many cases. Blood can also be transmitted to previously blood-free textiles during the washing process, leading to a positive Luminol or Combur® reaction of these samples. When traces of blood can be detected via the Luminol reaction, a molecular identification of the blood donor was successful in 28% of the cases.


Asunto(s)
Manchas de Sangre , Lavandería , Textiles , ADN/aislamiento & purificación , Dermatoglifia del ADN , Detergentes , Femenino , Ciencias Forenses , Humanos , Sustancias Luminiscentes , Luminol , Masculino , Reacción en Cadena de la Polimerasa , Temperatura
4.
Oecologia ; 187(3): 701-706, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29536162

RESUMEN

Botanical gardens represent artificial, but stable environments. With this premise, we analyzed the Munich Botanical Garden's bee fauna in 1997/1999 and again in 2015/2017. The garden covers 20 ha, uses no bee-relevant insecticides, has a protected layout, and on three sides abuts protected areas. Outdoors, it cultivates some 10,871 species/subspecies, many suitable as pollen and nectar sources for bees. The first survey found 79 species, the second 106, or 55% of the 192 species recorded for Munich since 1990. A Jackknife estimate for the second survey suggests 115 expected species. Classifying bees according to their thermal preferences (warm habitats, cool habitats, broad preferences, or unknown) revealed that 15 warm-loving species were gained (newly found), two lost (no longer found), and 12 retained, but only one cool-loving species was gained, three lost, and none retained, which multinomial models show to be significant differences. Of the 62 retained species, 27 changed in abundance, with 18 less frequent and nine more frequent by 2017 than they had been in 1997/1999. Retention, gain, or loss were unconnected to pollen specialization and Red List status of bee species. Between 1997 and 2017, average temperatures in Munich have increased by 0.5 °C, and climate warming over the past century is the most plausible explanation for the directional increase in warm-loving and the decrease in cool-adapted species. These results highlight the potential of botanic gardens with their artificially diverse and near-pesticide-free floras as systems in which to investigate climate change per se as a possible factor in shifting insect diversity.


Asunto(s)
Jardines , Néctar de las Plantas , Animales , Abejas , Ecosistema , Plantas , Polen
5.
J Anim Ecol ; 83(3): 681-92, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24102250

RESUMEN

The growing interest in the effects of light pollution on daily and seasonal cycles of animals has led to a boost of research in recent years. In birds, it has been hypothesized that artificial light at night can affect daily aspects of behaviour, but one caveat is the lack of knowledge about the light intensity that wild animals, such as birds, are exposed to during the night. Organisms have naturally evolved daily rhythms to adapt to the 24-h cycle of day and night, thus, it is important to investigate the potential shifts in daily cycles due to global anthropogenic processes such as urbanization. We captured adult male European blackbirds (Turdus merula) in one rural forest and two urban sites differing in the degree of anthropogenic disturbance. We tagged these birds with light loggers and simultaneously recorded changes in activity status (active/non-active) through an automated telemetry system. We first analysed the relationship between light at night, weather conditions and date with daily activity onset and end. We then compared activity, light at night exposure and noise levels between weekdays and weekends. Onset of daily activity was significantly advanced in both urban sites compared to the rural population, while end of daily activity did not vary either among sites. Birds exposed to higher amounts of light in the late night showed earlier onset of activity in the morning, but light at night did not influence end of daily activity. Light exposure at night and onset/end of daily activity timing was not different between weekdays and weekends, but all noise variables were. A strong seasonal effect was detected in both urban and rural populations, such as birds tended to be active earlier in the morning and later in the evening (relative to civil twilight) in the early breeding season than at later stages. Our results point at artificial light at night as a major driver of change in timing of daily activity. Future research should focus on the costs and benefits of altered daily rhythmicity in birds thriving in urban areas.


Asunto(s)
Ritmo Circadiano , Luz , Actividad Motora , Pájaros Cantores/fisiología , Animales , Ciudades , Alemania , Iluminación , Masculino , Telemetría
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