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Die neue Salonfähigkeit geschickt frisierter Neonazis, die ihre eigene Sprache nicht beherrschen

Eine wohl dosierte Portion aus Fremdenhass, rechtem Patriotismus, naiver Weltanschauung, gepaart mit einer fröhlichen Neigung zu populistischen Verschwörungstheorien und nationalsozialistischer Rhetorik, wird vorwiegend in ländlichen Regionen unseres schönen Landes zunehmend zu einem Menü intellektueller Verblödung, das man nicht mehr aus Scham verbergen muss.

 

 

alligator

Ein demaskierter reptiloider Unruhestifter, der es auf die deutsche Rechtschaffenheit abgesehen hat, Urheberrecht des Fotos: Stefan F. Wirth

 

angst

Blick in die dunklen Abgründe unserer Erdenscheibe, Urheberrecht Foto: Stefan F. Wirth

 

 

Keine Macht den Reptiloiden, die absichtlich Sachen in unser Land rein holen, die wir nicht kennen und auch nicht mögen

 

 

Da werden absichtlich Schwerverbrecher und Vergewaltiger nach Deutschland importiert, sagen wir „rein gelassen“, um das Idyll aus deutscher Rechtschaffenheit und Nächstenliebe ein für alle mal zu zersetzen. Nur eine versiffte linke Weichbirne käme auf den Gedanken, zu fragen, welche geheimen Mächte all diese Fäden führen und vor allem warum. Nein, mit primitiver Hinterfragung und versiffter Antifa-Rhetorik braucht man einem braunen Schrumpfhirn von heute wahrlich nicht zu nahe zu treten. Schließlich weiß doch jeder, dass es die außerirdischen Reptiloide sind, die versteckt in jenem dunklen Höhlenlabyrinth zwischen der oberen und der unteren Erdenscheibe hausen, die aus blanker extraterrestrischer Bösartigkeit heraus das naturgegeben reine und friedfertige Idyll deutscher Bräsigkeit mit einer ungeheuerlichen Katastrophe überziehen, nämlich der Veränderung von Dingen, die doch seit jeher gleich geblieben waren. Also zumindest seit jenen Zeiten, in denen der Besitzer des jüngst versteigerten schwarzen Faltzylinders noch das Sagen hatte.

 

Links-rot-grün versiffte Zero-Hirne

 

 

Das ist doch alles glasklar und bedarf keiner weiteren konstruktiven Nachfrage stinkender links-roter Zero-Hirne. So kryptisch wie die Hieroglyphen-gleichen Muster der bedrohlichen Chemtrails am Himmel, mit denen uns die fiesen Reptilien-Aliens ihre vernichtenden Absichten unter Beweis stellen, erscheint dem aufgeweckten deutschen Neu-Nazi allerdings leider zunehmend das Wirrwarr der eigenen Sprache, die dem aufrechten Alemannen mit ihren Regeln der Orthographie, der Grammatik und der Zeichensetzung geradezu den letzten Funken Verstand rauben kann. Zum Glück ein sehr geringer Diebstahl, der gut zu verschmerzen ist, solange man noch stolz und mit erhobener Brust laut genug ausrufen kann: Tod den Reptiloiden, die immer mehr Sachen rein holen, die wir nicht kennen und auch nicht verstehen! Wir haben das perfide Spiel durchschaut, das uns weismachen will, dass Ausländer mit andren Hautfarben gleichwertige Menschen seien und es auf unserer schönen Erdenscheibe ein durch menschliche Emmissionen veränderliches Klima oder gar einen Treibhauseffekt gäbe (Dreibhausefegd, Traubhaußeffekht, Draibhaussäphegght??? Egal!).

 

SS855560

Untrüglicher Nachweis ihrer Existenz: brauner Reptiloiden-Kot auf einem Stein, Urheberrecht Foto: Stefan F. Wirth

 

German written article against right-winged ideologies.

 

Copyrights Stefan F. Wirth, Berlin November 2019

 

Drone flights: Worth seeing nature around the fields of Berlin

The metropolis Berlin is the capital of Germany and much more than that. It represents an unusual green city. When using elevated viewpoints to watch the cityshape, then at least in summer visitors of Berlin can receive the impression of being in the midst of a greening huge landscapes with several villages in between.

 

Green areas in Berlin

 

 

Indeed related to other metropolitan cities of the world, Berlin is still partly not very densely populated and covered by remarkable huge natural countryside instead. The area of landing and runway strips of the former airport Tempelhof for example up to date represents the largest coherent green area inside a city worldwide. The so called Tempelhofer Feld was after the termination of the air traffic exposed to renaturation and is currently a very popular recreational park. It’s located in the South of the city.

Also the West and South-West partly represent nature reserve areas and are covered by the big urban forest Grunewald.

 

Meadows and wetlands in the North of Berlin as nature refuges

 

I am since two years discovering the Northern parts of Berlin, which according to my random observations (in comparison with other Berlin areas, such as Tempehofer Feld, Teufelsberg (Grunewald) and some urban parks in the center of the city; examples of species will be visible on my corresponding blog article) bears the greatest biodiversity in bloom visiting insects.

 

 

 

Mosaic of different landscape types close to each other

 

 

 

 

 

This is seemingly due to the complexity of different meadow-, field-, wetland- and bog-habitats, being originally shaped by the Weichselian-glaciers. I regularly visited the stream valley of the so called Tegeler Fließ with the lake Köppchensee. It’s a hilly area with different gradients of sunny slopes with partly Mediterranean climatic conditions, surrounded by different kinds of wetlands. This area is well known for its great biodiversity.

 

Between the villages Rosenthal, Lübars and Blankenfelde

 

But my drone flights present vast tracts in the South of that stream valley, consisting of fields, green meadows and wetlands. It is the area between the Berlin villages Rosenthal, Lübars and Blankenfelde. Inner urban agriculture is rare in metropolian cities worldwide, in Berlin there is only a small agriculture area in the South (Dahlem Dorf) and the fields between the named villages in the North.

 

Drone flights and bloom visiting insects

 

 

Fields and meadows with adjacent forests and wetlands in the North of Berlin, September 2019, copyrights Stefan F. Wirth. Please give my video also your like on Youtube.

 

Most part of the footage in my film represents the fields adjacent to the village Rosenthal. I newly discovered the partly quite tiny meadows between and adjacent to agricultural fields around Rosenthal this summer and discovered an impressive and steadily visible diversity of bloom visiting insects there. Fields as monoculture habitats usually bear a smaller biodiversity related to wild-growing nature zones. But due to the connection of the edges of fields with complex nature refuge zones around, I could observe a quite great number of species on closely adjacent meadows and even the natural border zones of these agricultural areas.

 

Videographic details

 

The footage was captured in 4K and D-cinelike quality using a Mavic 2 Zoom drone between September and October 2019.

 

 

Berlin, September/ October 2019, copyrights Stefan F. Wirth

 

Different wing colors in a harlequin ladybeetle specimen

The ladybeetle Harmonia axyridis is naturally distributed over eastern Asia, but was imported to the United States already at the beginning of the 20th century as pest control. At first, there was no population development in the open fields. These were at first reported from Louisiana in 1988. In 2001 the first free living specimens were for Europe discovered in Belgium. Since then the beetle distributed over several European countries, such as France, entire Germany or Switzerland.

 

Variations of Harmonia axyridis

 

The beetle is well known for its great form variations. Worldwide more than 200 different color pattern forms of thorax and elytrae are described. They are distinctly shaped and maintain in this shape and arrangement of pattern. But four forms dominate within natural populations. Speaking about the elytrae (not the thorax patterns), the reddish form with dark spots, as visible in my film, is one of them.

These distinct different forms must be named a polymorphism and are based on genetic information as well as on environmental conditions, such as temperature, humidity and light intensitivity. According to that even the term polyphenism might be adequate.

 

 

 

 

Transcription factor pannier responsible for color pattern polymorphism

 

According to the work of M. Gautier et al. (the genomic basis of color pattern polymorphism  in the harlequin ladybird, Current biology, 28, 20), the transcription factor pannier is responsible for the genetically based control of this polymorphism. They discovered that different pannier alleles determine the color pattern in the different known forms. The authors furthermore report that pannier was never found before to play a keyfactor role in the pigmentation of insects.

 

Ladybeetle species on a meadow in Berlin

 

The specimen in my footage was discovered on an urban meadow in the park area „Nordhafen“ in Berlin. It’s a meadow in autumn predominantly consisting of lucerne and clover, sorrel and yellow field cress. Different ladybeetle species could be in greater numbers found there between September and October 2019. The sevenspot-ladybird, the adonis ladybird (Hippodamia variegata) and most abundant the harlquin ladybird in all its developmental stages.

 

Asymmetrical wing colors and possible explications

 

 

Harlequin beetle specimen from Berlin with asymmetrically colored wings, copyrights Stefan F. Wirth, please like my video also on Youtube

 

The most conspicuous character of „my“ harlequin ladybird specimen was its distinct asymmetrically colored wings (elytrae). One side reddish with black spots, the other side brownish with black spots. During my research about such asymmetries in ladybirds, I didn’t find recent studies, which distinctly focussed on that topic. H. E. Roy et al. reported in their book „ladybirds“ (original version 1989, revised version 2013) about the existance of such differently colored wings in the same specimen. They emphasized that the phenominon was not studied in detail, but assumed different factors being eventually responsible for such a development of a beetle individual: 1) disruption of pigment production, 2) mitotic mutation in early development, 3) environmental conditions, eventually influencing the colors of an originally normal developed young adult (exposed for longer time to different light intensities etc.). The latter might in the case of „my“ specimen being an indeed possible factor, as it is clearly visible that also the brownish wing has at its edges some of the reddish pigments.

 

 

Filming/ photography conditions

 

The beetles was filmed and photographed under artificial conditions in a soil and grass-set in my video lab. There, mites of the Gamasina (Parasitiformes, evtl. mostly Laelapidae) were common. They interestingly showed a phoretic behavior by quickly climbing onto the wings of that ladybeetle. They obviously recognized it as a suitable carrier to new habitats. I assume ladybeetles in the field not being of much attraction for phoretic dispersal, based on their life-cycles and preferred habitats.

 

Berlin, September/ October 2019, Copyrights Stefan F. Wirth

Diving, feather cleaning and water bathing of the Inca tern Larosterna inca


Inca terns live along the South American Pacific coast and breed along rocky coastlines of Peru and North Chile. They can be easily identified by their grey plumages, their distinctly red beaks and feeds as well by their conspicious white feather curls on the bases of their beaks.

 

Geographic distribution and life-strategy aspects of Larosterna inca

 

Larosterna inca breeds inside rocky walls of coastlines either inside rocky cavities or in old nesting holes of other seabird species. Its hunting ground is the  Humboldt Current, which is famous for its cold temperature, but also its enormous fish wealth. To increase its chances for fishing success, the Inca tern might follow sea lions, cormorants and whales  and is then hunting fishes, which were flushed up by these bigger sea animals. They also follow fisher boats to catch some rests of their fishery.

 

Phylogenetic (systematic) relationships

 

According to phylogenetic reconstructions L. inca, which represents the only recent species of its genus, branches off in the Animalia tree within the monophyletic clade of terns. Based on DNA sequences E. S. Bridge, A. W. Jones and A. J. Baker reconstructed in their 2005 paper (Molecular phylogenetics and evolution) a sister-clade relationship between Larosterna and species of the taxa Sterna, Thalasseus and Chlidonias (mitochondrial DNA was used to reconstruct the tern phylogeny).

Terns themselves seem representing an own clade (Sternidae), being for example based on characters of behavioral pattern, and are considered as a sister taxon of gulls (Laridae).

 

Filming conditions and filming locality

 

My footage was recorded in the Zoo Berlin, where terns together with other sea birds inhabit a for tourists accessible free-flight enclosure. There I captured scenes about the diving and „fishing“ behavior (specimens fished repeatedly wooden sticks) as well as their plumage cleaning activities on shore and their conspicuous plumage cleaning behaviors via extended bathing trips inside areas of low water. Size of my entire video is 4K. But parts of the scenes were originally recorded in Full HD to enable a better slow motion effect based on 100 frames per second. Such footage was subsequently digitally magnified into the 4K size to fit in the entire video project.

All behavioral activities are at first presented in a slow motion (ca. three to four times slowlier than  original speed), then in the much faster original speed.

 

Plumage cleaning

 

Plumage cleaning is part of the hygienic behaviors of birds. Feathers can only stay in full function, thermoregulation and flying, when dirt and parasites are removed regularly. Typical plumage parasites are represented by feather mites (no phylogenetic clade), which consist of taxa of the Astigmata (Acariformes) and of taxa of the Dermanyssoidea (Parasitiformes). Feather lice represent  a subclade of the (Phthiraptera = lice), named Mallophaga. The monophyletic situation of Mallophaga is seemingly doubtful.

 

Plumage cleaning and hunting behavior of Larosterna inca, video (4K9, copyrights Stefan F. Wirth. Please like my video on youtube too.

 

Putative reasons for plumage cleaning behaviors

 

I couldn’t research sufficient information about specific plumage parasites of Larosterna inca. There is indication that terns generally are relatively free of predators and parasites. Seemingly, plumage parasites of this particular species are still a more or less open research field. But the existence of a regular and visibly careful plumage cleaning might indicate a sensitiveness for corresponding parasites. L. inca can be according to literature (e.g. W. Pieters et al., Avian Diseases, 2014) fatally infested with the trematode Ichthyocotylurus erraticus.

 

Copyrights Stefan F. Wirth, Zoo Berlin July/ September 2019

Complex and modified mouthparts in Histiostomatidae mites

Mites represent arachnids, which means that they share characters with much bigger organisms, such as spiders, skorpions or harvestmen. Their bodies consist of specialized bundles of segments, named tagmata.  Two major tagmata are differed from each other in arachnids: prosoma, including legs and mouthparts, and opisthosoma, including for example the digestive and the reproductive systems.

 

Diphyletic origin of mites

 

Mites are not longer just mites. The former two clades of mites, Parasitiformes and Acariformes, originally considered as sister taxa, were in the modern systematics reconstructed to be diphyletic. That means, there was no commor ancestor, from which only those two clades derived.  There is no close relationship between them,each clade is most closely related to different groups of arachnids.  Thus, when I talk about mites, I am talking about the clade Acariformes.

 

Mites of the Acariformes and body plan

 

In these Acariformes mites, the arachnid body construction plan was modified into three visible tagmata: gnathosoma (bearing chelicerae and pedipalps as mouthparts), proterosoma (bearing first two leg pairs) and hysterosoma (bearing last two leg pairs and opisthosoma organs).

 

big male 2 Saarland compost

Male (large morph) of mite Histiostoma feroniarum in dorsal view. Body division in gnathosoma, proterosoma and hysterostoma. Fixation : critical-point-dried, SEM photography, copyrights Stefan F. Wirth

 

 

Mouthparts

 

Let’s talk about mouthparts, as they are an important aspect of my systematic and my function.morphological studies. Originally the gnathosoma consists of a pair of scissor-shaped chelicerae to grasp the food particles and of a pair of leg-shaped pedipalps, which mostly have mechano-sensitive and chemo-sensitive functions. But because mites colonized almost all kinds of existing habitats on earth, they extensively were exposed to the mechanisms of evolution. Acariform mites show a high range of variability regarding their morphology and their life strategies.

 

Mouthparts of Sarcoptiformes

 

Within the clade Sarcoptiformes, consisting of oribatid and astigmatid mites, there evolved a tendency towards miniaturization. Mites of the Astigmata are usually much smaller than one mm. Correspondingly the cuticle becam thinner and softer, perfect adaptations to a life inside very tiny micro habitats, but at the same time also a limitation, namely towards more or less moist habitats due to the lack of a well developed desiccation protection. They appear inside compost, rotting wood or mammal dung, being even there very specifically adapted into very defined micro climatic conditions. They live in a world of complete darkness, which is why light sensory organs are completely lost or reduced to vestigial structures.

Inside their habitats, astigmatid mites need to reproduce, to develop through different nymphal stages until adulthood and of course to feed. Astigmata are no fluid suckers, but feed on particles, such as bacteria, algae, fungi, thus many Astigmata taxa can be named microorganism feeders.

 

Life-strategy of mites of the (family) Histiostomatidae

 

Rollei Digital Camera

Extinct bark beetle fpssil in amber (collection Hoffeins) with phoretic mite deutonymphs. Fixation with hexamethyldisilazane, stereomicroscopic photography, copyrights Stefan F. Wirth

 

One of the largest family within the Astigmata clade is the Histiostomatidae, which I use since many years as model for my scientific studies. These mites are scientifically interesting from different points of view. Their ecology is characterized by life styles, which correspond to the life cycle of insects and other arthropods, to which most species have a close association. Most important aspect of these interactions between mites and other arthropods, commonly insects, is a dispersal strategy named „phoresy“. Mites use their „partners“ as carriers from one habitat to another. These habitats can often be the nests of the corresponding arthropods/ insects.

Habitats, in which mites of the Histiostomatidae develop successfully need to be moist and need to contain a sufficiant amount of microorganisms as food source. It is the most conspicuous feature of these mites to possess  remarkably modified mouthparts compared to the above described standard equipment of an acariform gnathosoma.

 

Mouthparts of the Histiostomatidae

 

 

Mite Histiostoma sp. (sapropel around ponds, female, Berlin) feeding from a substrate surface inside its original habitat. Videography in 4K, copyrights Stefan F. Wirth

 

The character conditions of the gnathosoma were one of the reasons, why I at the beginning of my phd thesis in 2000 decided to put my research focus on this mite family, being worldwide in major still unexplored.

The chelicera modified into a dagger-like structure being formed by the fixed part of the former scissor-like organ, named the digitus fixus. There is a variability of shapes of this digitus fius-chelicera-ending within the Histiostomatidae . It can appear „simple-dagger-like, simple formed with a hook-like ending or having cuticular dentations of specific numbers and sizes along the lower edge of the digitus fixus.

As typical for mites of the big clade Astigmata, the pedipalps are reduced in size and almost immovably ventrally and dorsally connected with each other. In Histiostomatidae, the third pedipalp article is additionally distinctly bent sidewards. Their front sides bear more or less complex arrangements of flexible membraneous structures, which can morphologically differ between taxa or even species, thus giving them a systematic relevance. I named these membrane-organs „palparmembrane“ following the nomenclature, introduced by R. Scheucher in 1957. These membranes can be devided into fringes or being lobe-sphaped and can cover the last pedipalp article dorsally and/or ventrally. My histological analysis from 2006 indicated that these membranes are shaped by the enditesof the pedipalpal coxae.

 

Complex mouthpart apparatus

 

Thus Histiostomatidae possess a bizarre mouthpart apparatus being unique within the Acariformes and representing an amount of characters, which from the phylogenetc point of view  can be reconstructed to have evolved in the stem species of that family (so called apomorphies).

 

Mouthpart apparatus as multifunctional organ

 

 

Mite Histiostoma sp. (male left, female right) feeding from a substrate surface inside its original habitat. Fixation with hexamethyldisilazane, SEM photography, copyrights Stefan F. Wirth

 

This gnathosoma is a multifunctional organ with the main function to select specific microorganism particles out of their liquid environments. When observing a histiostomatid mite with a sufficient high magnification walking along on a smooth water agar surface, on which bacteria and fungi growth was stimulated before, then occasionally trails can be seen around the walking mite, indicating that the gnathosoma was hold mostly leaned downwards towards the ground, pushing the microorganism cover along in front of the mite’s body. I interpreted this as an accumulation of food in order to gain more nutrients all at once. In my early papers, I described this as the typical feeding behavior of histiostomatid mites with the membraneous appendages acting like rubber sliders in the meantime. But as newer analyses showed is that such observations do not describe the full equipment of possible applications of the mite’s complex filter-feeding apparatus.

 

Membraneous structures create an underpressure to incorporate food

 

 

Mite Histiostoma ruehmi mouthpart endings with palparmembrane in ventral view. Fixation with hexamethyldisilazane, SEM photography, copyrights Stefan F. Wirth

 

More recent experiments with a higher videographic resolution and more suitable light conditions than 10 years ago (through-light and up light or one of them depending on the setting) showed that the palpar membrane structures , which more or less surround the entire fore-part (anterior part) of the gnathosoma can act like suckers: When the mite presses its front end of the mouthparts  to the underground, an underpressure can be formed based on these membraneous structures. This seemingly facilitates the incorporation of nutrients in that area. I presented such video footage in one of my former mite videos. To get off from the underground requires a jerky upward movement of the whole mouthpart apparatus (also visible in that older video). As I observed different developmental stages of different species, I could conclude that on a smooth surface with randomly dispersed food supply, regular stops and mouthpart-sucking-activities are seemingly a most common behavior of histiostomatids, while a straight forward walking behavior with the gnathosoma permanently touching the ground in order to push microorganism covers to the body`s front side only than occured, when food supply was uniformly dispersed (under artificial experimental conditions) under uniform moisture conditions.

 

Mite Histiostoma ruehmi and an undetermined species feeding from a smooth artificial substrate surface and performing an underpressure to incorporate food. Videography, copyrights Stefan F. Wirth

 

 

Scanning-electron-microscopic experiments

 

Mite Histiostoma feroniarum feeding from a substrate mount inside its original habitat. Fixation with hexamethyldisilazane, SEM photography, copyrights Stefan F. Wirth

 

Mite Bonomoia opuntiae feeding from the surface of a substrate mount inside its original habitat. Rounded particles might represent yeast bodies. Fixation with hexamethyldisilazane, SEM photography, copyrights Stefan F. Wirth

 

 

In my early postdoc-years, still at the FU Berlin, I performed experiments in order to fix mite activities inside their original substrates by filling such a mite-substrate-setting up with 1,1,1,3,3,3-hexamethyldisilazane and warming the corresponding small experimental dish, until the chemical was vaporized. I then sputtered the conserved setting with gold and studied the details on it via scanning-electron-microscopy. Occasionally, mites were shrinkled or deformed after this procedure, but sometimes they stayed in shape and did seemingly still remain in their last activity positions. I several times could take SEM photos, showing that (well visible only in adult mites due to their size) mite specimens can insert their (distal) chelicerae-endings into bigger heaps of substrate (obviously full of nutrients) and use the entire laterally bent pedipalpal articles, including the connected palparmembranes, to lean it against the substrate surface, either to stabilize the chelicerae movents or even to support the incorporation of nutrients again by forming a slight underpressure, or both.

 

Mite species Bonomoia opuntiae

 

Early observations during times of my phd-thesis on the mite Bonomoia opuntiae could show that the mouthpart apparatus of this terrestrial/semiaquatic mite works well also under water or inside a watery juce of decomposing cactus pieces. There even a filter function comparable with a fishing net was hypothesised, but so far was never studied in detail. The very distinct fringes along the palparmembrane lobes in this mite species might support this theory. I also studied the semiaquatic mite Sarraceniopus nipponensis feeding inside watery environments (normally the digestive fluids of Sarracenia pitchers), again never focussing in detail in how excactly the feeding mechanism works.

 

A putatively new species

 

The herewith presented video shows behaviors of  a female of the putative new species Histiostoma sp. , which I discovered in beginning of 2019 in sapropel around ponds inside an old gravel pit area in the Berlin forest Grunewald. The footage is presented in slow motion. The question was about how motile the whole gnathosoma apparatus in a histiostomatid species can be and what kinds of movements occured. As the settings, which I in early years of my mite studies used for videographic studies, were simplyfied and thus unnatural (smooth agar surfaces), I thought it being necessary and important to capture behaviors in a complexly sculptured habitat, namely surfaces of decomposing potato pieces (on which most histiostomatid species use to develop well).

 

It was visible, based on the specimens of my video of this species, that histiostomatid mites can be able to lift up their entire gnathosomas on a sometimes even higher position than the levels of the rest of their bodies. Additionally the gnathosoma can be turned to the right and to the left. Up and down as well as sideward movements of the whole feeding apparatus were often performed and represented obviously flexible reactions of the mite to the surface structure of the substrate and to the availability of suitable nutrients. In this context I was also interested in details of the movements of the chelicera tips themselves.

 

Chelicera endings (digitus fixus)

 

Although they can be used dagger-like and be accurately inserted into muddy substrate mounts, chelicera tips will also appear in a very fragile and seemingly careful way, when palpating the surface of the substrate underneath. Such chelicera movements are visible in the footage of this video, presented in slow motion (about 25 percent of original speed) and in a digital magnification. I interpret this visible fragility caution of the chelicerae as one option to discover suitable food sources. Other important organs perceive the mite’s environment chemically, modified setae, namely the so called solenidia, which might additionally recognize profitable microorganism sources.

 

Fig. 2

Mite Histiostoma feroniarum feeding from substrate mounts inside its original habitat (A-F). Rounded particles might represent yeast bodies. D = distal chelicera endings (digitus fixus), holding food particles, fixation with hexamethyldisilazane, SEM photography, copyrights Stefan F. Wirth

 

Berlin, September 2019

 

Copyrights Stefan F. Wirth

Countryside of Berlin: urban green in a drone view (4K)

Many tourists from overseas use to visit European cities in a much too short time. For this reason they often miss an entire picture of for example the city Berlin, when inserting an only short interstop here. Especially winter tourists can experience the German capital as a sad a grey urban being with some architectural major sites and a remarkable party life only.

 

Climate and landscape types in Berlin

 

Berlin has a continental climate and shows a completely other face in summer. It’s a very green face. Not only is the center of the city then colorfully greened by numerous urban parks, which partly lay almost adjacent to each other, but also the outskirts, in major parts covered by forests and grasslands or fields, appear like green oases.

 

 

Countryside of Berlin as aerial videography, Copyrights Stefan F. Wirth, Berlin June 2019. Please give my video on youtube a like, in case you like it.

 

 

Lübarser Felder and surrounding

 

Lübarser Felder is an area of agriculture, being under the management of inhabitants of the adjacent village Lübars, which represents the only Berlin village that still practices agriculture. The village has a long history and still has architectural monuments, dating back to the 19th century. Lübarser Felder lay adjacent to a nature refuge area more in the north, consisting of different kinds of wetlands, such as bog meadows or lowland fens. Lake Köppcensee as part of that nature refuge area is visible from a bigger distance in one scene of my video.

 

Püttberge and surrounding

 

The sanddune-mounts Püttberge are located in the east of Berlin and belong to the nature refuge area Wilhelmshagen-Woltersdorfer Dünenzug. The area consists of sandy mounts, some of them reaching a height of up to 68 meters. They are part of the glacial valley of Berlin, which dates back to the Weichselian glaciation, which happend between 115,000 and 11,700 years ago and covered almost the whole Northern Europe. The dune elevations of Püttberge were formed due to windblown sand inside the glacial valley. My footage shows the Wilhelmshagen-Woltersdorfer Dünenzug in a greater distance seen from the edge of the whole area. Ecologically the Püttberge are characterized by numerous plants and animals, being typical for sanddune environments.

 

Lieper Bucht at river Havel

 

Lieper Bucht is a bathing beach area at river Havel, belonging to the Berlin city district Nikolassee in the South-West of Berlin. The adjacent forest area is the huge urban forest Grunewald. The riverside of Havel in Berlin is geologically charactrized as sandy with a tendency to the formation of dunes, being like Püttberge a relict of the Weichselian glaciation. Flora and fauna are correspondingly composed. Pine trees for example are typical representatives. The nearby Havel islands Lindwerder and Schwanenwerder are visibe in my footage.

 

Berlin, June 2019

Copyrights Stefan F. Wirth

Pompeii, ancient Roman city under a dynamic sky

Ash layers preserved almost the entire city

 

The ancient Roman city Pompeii is famous for its incredible conservation status. Huge ash layers preserved all anorganic remnants of the city and its inhabitants. Also organic tissue persisted in partly remarkable conditions, but can not be compared with artefacts, which survived the destruction of the neighbour city Herculaneum. There lava rocks enabled an airtight seal and thus could shield decomposing microorganisms.

 

Well visible sky over the city of no roofs

 

Unlike Herculaneum, Pompeii is also famous as the city without roofs. And indeed, when walking through the vast excavated area of ancient ruins, no higher buildings are shading or obstruct a free view to the sky. Exactly these phenomina male sauntering through Pompeii so unique. The sky with its seasonal dynamics is from everywhere always well visible and due to in spring or in autumn sometimes rapidly changing weather conditions, a dramatic atmosphere based on powerfully moving cloud formations can occur.

 

 

 

 

Pompeii/ Berlin April/June 2019 Copyrights Stefan F. Wirth

Agriculture, natural countryside and stream pasture landscape north of Berlin

Berlin as a green city

 

 

Berlin, lake Köppchensee, March 2019. Copyrights Stefan F. Wirth.

 

Berlin is an unusually green metropolis. Besides numerous urban park landscapes and the huge forest area Grunewald, there is a unique countryside north of Berlin, including the area of the old village Lübars, being surrounded by numerous fields (Lübarser Felder) and a stream pasture landscape, named Tegeler Fließ, with bog meadows.

 

 

Nature sites Lübarser Felder, Arkenberge, Schönerlinder Teiche in 4K, copyrights Stefan F. Wirth. Please also like my video on Youtube.

 

Mounts Arkenberge and pondlandscape Schönerlinder Teiche

 

In the northeast, around the urban village Blankenfelde, the currently highest elevation of Berlin can be found, the Arkenberge. Originally, they represented a chain of smaller mounts as natural remnants of the Weichselian glacier. One of these mounts is especially conspicuous and is acually prepared to become accessible for people and forms with a height of 122 m over NHN the highest mountain of Berlin. It represents despite of its natural origin a rubble landfill site, which was formed beginning in 1984.
Adjacent to the Arkenberge, several wetland areas attract nature enthusiasts for hiking tours: the pond landscape „Schönerlinder Teiche“ (Brandenburg) and the lake Kiessee Arkenberge.

 

Mount Arkenberge with Kiessee Arkenberge, Berlin March 2019. Copyrights Stefan F. Wirth.

 

Mount Arkenberge, Berlin February/ March 2019. Copyrights Stefan F. Wirth

 

Eurasian blue tit at Schönerlinder Teiche (Wandlitz), February/ March 2019. Copyrights Stefan F. Wirth.

 

Ponds Schönerlinder Teiche (Wandlitz, Brandenburg), February/ March 2019. Copyrights Stefan F. Wirth.

 

Lowland area of the stream Tegeler Fließ as remnants of the Weichselian glacier and adjacent calcareous tufa area

 

The stream Tegeler Fließ is a wetland nature site with a high biodiversity of plants and animals. It is surrounded by different types of bog meadows. The Tegeler Fließ lowland is also a result of the last glacier period.

The stream lowland is additionally adjacent to a calcareous tufa area, which is well visible from top of the Arkenberge. Calcareous springs and calcareous tufas created here calcareous rush- marshes with an interesting biodiversity of for example species of mosses and snails.

 

Lake Köppchensee as part of the Tegeler Fließ lowland, March 2019. Copyrights Stefan F. Wirth.

 

Video footage and photos

 

The footage was captured from localities around the village Lübars in the area of Lübarser Felder and additionally around Arkenberge. Some above mentioned nature sites are only visible in a distance.

 

Berlin, March 2019, copyrights Stefan F. Wirth.

 

Late winter insect life: winter aconite blossoms and dipteran visitors

When do the first insect activities in the new year occur? Can insects be active in winter, even in the presence of snow? The answer is generally yes, different insect species even use to appear on warmer winter days on top of snow layers. Examples are the limoniid crane fly Chionea belgica, a wingless dipteran, which can be observed on milder winter days on snow surfaces along forest edges in Central Europe. Also the fly Trichocera hiemalis belongs to the winter crane flies (Trichoceridae) and can be characterized by a very well developed cold resistance. It appears on sunny winter days between branches of leafless trees in swarms around invading sunlight beams.

 

The winter aconite as an early blooming flower and its biology

 

But what about insects, visiting blooming flowers? This requires the existance of early blossoms, which can grow and bloom under winter conditions. A well known example is the winter aconite Eranthis hyemalis, which outlasts the summer period only by its underground tubers. Their conspicuous yellow blossoms belong to the first blooming flowers in the year. In Central Europe, they begin to grow under suitable conditions in mid February. They require milder temperatures, but even persist in case an unusual cold snap would happen. The blossoms open only at sunshine and thus close shortly after sunset. Opening and closing is a growth process, which depends on temperature conditions. Such a phenomenon is called thermonasty.

 

The winter aconite as a neophyte in Germany

 

In Central Europe, such as in Germany, E. hyemalis is a neophyte. It is originally native to Southern European areas, Turkey, South-East-France, Italy, Bulgaria and Hungary.

The species was introduced to Central Europe (and North America) as ornamental plant for gardens. It is proven that it was in Germany already cultivated since the 16th century. The German botanist, nature researcher and medical doctor Joachim Camerarius reared the winter agonite, which he brought from Italy, since 1588 in his backyards.

 

Common pollinating insects

 

Pollinating insects of E. hyemalis are flies, bumblebees and bees. To reach the nectar inside the blossoms requires a proboscis length of about two mm, which is mostly given in bumblebees and bees.

 

Flowerbed in Berlin urban park Schillerpark

 

I documented via my videography (4K) and photography a smaller area of winter aconites in front of a wall at urban park „Schillerpark“ (honoring the German poet Friedrich Schiller) in Berlin. The bright bricks of that wall reflected efficiently the solar warmth and thus created suitable conditions for a late winter flowerbed full of life.

 

Video with winter aconite blossoms and pollunating flies, copyrights Stefan F. Wirth.

 

Most abundant insects in that winter aconite bed

 

DSC03573bestsharpsignatur

Western honey bee, copyrights Stefan F. Wirth

 

The western honey bee Apis mellifera was often seen on blossoms, but unfortunately was not captured via video footage. Our honey bee hibernates in a so called winter clusters with lower temperatures and low activities in workers. Beginning in late winter/ early spring, workers increase the nest temperature due to body movements up to 35°C. This is exactly the body temperature, workers need to fly out and collect first nectar and pollen, for example from the winter agonite.

 

Drone fly on blossom of the winter aconite, copyrights Stefan F. Wirth

 

The drone fly Eristalis tenax belongs to the hoverflies (Syrphidae). Their larvae develop in watery environments, where they use their conspicuous snorkel tube to breath air at the water surface. Adults are typical blossom visitors, preferring Asteraceae and Apiaceae. Interesting highlight of their biology is the migratory behavior. These migratory insects form swarms, which cross the Alpes towards Southern European areas by using suitable wind conditions, where they finally hibernate and reproduce. The next generation returns the same way back. Not all individuals participate these migratory flights and would try to hibernate in Central Europe. Hibernating individuals are always females, which were fertilized prior to their winter diapause or their migration and which lay their eggs in the subsequent spring or in southern regions during winter. In Germany they only survive in greater numbers in milder winters, which they persist in temperature-stable hideways, such as gaps inside walls or wooden habitats. These specimen can be usually observed early in the year, beginning with March, when visiting blooming flowers. Their numerous very early appearance in mid February 2019 might be due to a very warm summer 2018 and a subsequent very mild winter in north-eastern Germany (Berlin). I have no comparative findings regarding the usual blooming time of the winter aconite and the abundance of drone flies there for Berlin or even this specific urban park. I also don’t know about indications that due to a global warming, as in some migratory birds, less specimens of the fly would migrate and more stay to hibernate here around.

The research station „Randecker Maar“ in the Swabian Jura records changes in migratory flights of birds and insects. They discovered a distinct decline of numbers of migrating drone flies and interpret it as a result of the increasing application of poisonous substances in the agricultural sector. Whether they additionally consider this being due to more individuals hibernating, where they are, based on generally warmer temperatures (global warming) is unknown to me.

 

Blow fly on blossom of the winter aconite, copyrights Stefan F. Wirth

 

The blow fly Calliphora vicina is a common blossom visitor in early spring and autumn. This fly, typically appearing in human settlements in Europe and the New World, is well adapted for an activity at lower temperatures (more than 13°C). While larvae develop in decomposing organic tissue (such as cadavers of animals), adults feed on nectar and pollen. They additionally incorprate saps from organic material with a strong odor.

C. vicina produces about five generation per year and throughout the year. The flies can even be active in winter, when temperatures reach a suitable level.

 

Other fly species were existant, but I did not determine them.

 

Time of footage and photo recording

 

Video footage and photos were recorded between 16 and 18 February 2019 in the urban park Schillerpark in Berlin.

 

Copyrights: Stefan F. Wirth, Berlin 2019.

Arapaima gigas, einer der größten Süßwasserfische – doch was sind Fische eigentlich?

Sie sind beeindruckende Fische, nicht nur aufgrund ihrer Größe. Und doch kennen die meisten Menschen sie nur aus den Aquarienhäusern zoologischer Gärten. Arapaima gigas wird mindestens zwei Meter lang und erreicht in Ausnahmefällen sogar Längen von über drei Metern. Beheimatet ist die Art im Bereich des Amazonas-Beckens und ist in Peru, Brasilien und Guyana verbreitet.

 

Arapaima gigas, einer der größten bekannten Süßwasserfische aus dem Amazonas-Gebiet

 

Arapaima ist ein Räuber. Erwachsene Fische ernähren sich von anderen Fischen sowie Tieren in vergleichbarer Größe, wie zum Beispiel auch kleineren Säugern. Besonders auffällig sind die kräftig gestalteten großen Schuppen, die den Körper der Tiere umschließen. Sie dienen unter anderem als mechanischer Schutz gegen Angriffe durch Feinde. So können sie beispielsweise den Attacken der im selben Lebensraum beheimateten Piranhas, die zwar wesentlich kleiner sind, aber bekanntlich empfindliche Beißwerkzeuge besitzen, wirkungsvoll widerstehen. Das schützt Arapaima freilich nicht vor seinem größten Feind, dem Menschen. Er ist ein beliebter Speisefisch, der durch massenhafte Bejagung in seinem Bestand immer wieder gefährdet wird.

Arapaima gigas wird häufig als größter Süßwasserfisch der Welt bezeichnet. Dies basiert jedoch auf Übertreibungen. In Wahrheit befindet er sich in der Größenordnung des Europäischen Welses, dem größten europäischen Süßwasserfisch.

 

„Fische“ ist keine spezielle systematische Gruppierung

 

Ich verwendete bislang stets unkommentiert den Begriff „Fisch“. Was sind Fische eigentlich?Welche sogenannte Fische kennt man noch? Wie verhält es sich beispielsweise mit dem Bullenhai, der über drei Meter lang werden kann und neben marinen Habitaten auch im Süßwasser auftreten kann. Kann er als Gigant des Süßwassers mit dem Arapaima, dem Gigant aus dem Amazonas verglichen werden? Nach evolutionsbiologisch-systematischen (=phylogenetisch) Gesichtspunkten kann er das nicht. Der Begriff „Fisch“ bezeichnet nämlich keine spezielle, systematisch in sich geschlossene Gruppe. Stattdessen haben wir es mit einem deskriptiven Begriff zu tun, der alle Tiere umfasst, die in ihrer Gestalt ganz grundsätzlich eine gewisse Ähnlichkeit mit dem Goldfisch aufweisen.

Wenn wir außer Acht lassen, dass auch „Tintenfische“ und „Walfische“ nach demselben Muster benannt wurden, die bekanntlich zu den Mollusken und Säugetieren gehören, weist die Fischgestalt zumindest in den meisten Fällen auf eine irgendwie gestaltete Verwandtschaft hin. Jedoch sind Haie und Arapaima dennoch nicht sonderlich nahe miteinander verwandt.

 

Arapaima gigas im Aquarium des Zoos Berlin, ein gigantischer Süßwasserfisch, der regelmäßig atmosphärische Luft an der Wasseroberfläche aufnehmen muss. Copyrights Stefan F. Wirth

 

Bei den „Fischen“ handelt es sich nämlich um eine sogenannte paraphyletische Gruppe. Das heißt, sie umschließt zwar eine ihnen allen gemeinsame Stammart, jedoch keineswegs alle dazu gehörigen Tochtergruppen. Dazu würden nämlich auch alle Landwirbeltiere gehören. Eine vergleichbare paraphyletische Gruppe stellen beispielsweise die „Reptilien“ dar, zu denen Eidechsen/Schlangen, Schildkröten, Krokodile und alle Dinosaurier gehören. Da die Vögel aus den Dinosauriern hervorgingen, jedoch nicht zu den „Reptilien“ gezählt werden, haben wir es unter dieser Bezeichnung wieder mit einer Stammart und nur einem Teil aller Tochtergruppen zu tun, die allerdings im Stammbaum der Tiere nebeneinander stehen und daher näher miteinander verwandt sind, so wie auch bei den „Fischen“.

Im Falle der „Fische“ (paraphyletische Gruppen werden häufig in Anführungszeichen gesetzt) verhält es sich so, dass die verschiedenen als Fische bezeichneten Gruppen neben nur ihnen eigenen Merkmalen auch unterschiedliche Merkmale aufweisen, die auf eine Ahnenlinie hin zu den Wirbeltieren zurückgeführt werden müssen. Was unterscheidet also Knorpelfische (zum Beispiel Haie) und Strahlenflosser (Actinopterygii = echte Fische) voneinander? Eine Frage, die so in der modernen Systematik, die stets nach Gemeinsamkeiten sucht, eigentlich nicht gestellt wird. Richtiger ist es, zu fragen: Welche Merkmale teilen die Knorpelfische mit den Landwirbeltieren (z. B. knöcherner Schädel, Kiefer) und welche die Strahlenflosser (z.B. Lunge). Wenn man dennoch über Unterschiede sprechen möchte, ist festzustellen, dass Knorpelfische noch keine Lunge, die mit jener der Landwirbeltiere homolog ist, besitzen, Strahlenflosser aber schon. Die Lunge ist also auf der Ahnenlinie der Knorpelfische hin zu den Strahlenflossern evolviert. Anders als die „Fische“ sind die Strahlenflosser, die ich hier auch als echte Fische bezeichne, sehr wohl eine geschlossene systematische Einheit (=Monophylum), die auf Merkmale einer gemeinsamen Stammart zurückgeführt werden kann, die nur dieser Gruppe eigen sind. Ein Beispiel ist die namengebende Gestalt der Flossen, die durch Flossenstrahlen durchsetzt sind.

 

Zuerst gab es Lungen, aus denen Schwimmblasen evolvierten

 

Die Strahlenflosser (Actinopterygii), zu denen neben unzähligen Arten auch Arapaima gehört, besitzen also in der Tat ursprünglich paarige Lungen als Respirationsorgane. Diese sind demzufolge nicht erst vor dem Abzweig der Lungenfische entstanden, die als nächste Verwandte der Landwirbeltiere gelten. Die dortige Neuerung betrifft, anders als der Name Lungenfisch vermuten lässt, die Evolution eines Lungenkreislaufs, den es bei urtümlichen „Fischen“ mit Lunge noch nicht gegeben hat.

Aber besitzen echte Fische (Actinopteryii) nicht Schwimmblasen und atmen ausschließlich durch Kiemen? Mitnichten. Ursprüngliche Vertreter der echten Fische werden beispielsweise durch die Flösselhechte (Polypteriformes) representiert, die paarige sackförmige Lungen besitzen und neben der Kiemenatmung daher auch atmosphärische Luft veratmen können. Diese beeindruckenden Tiere können sich mithilfe ihrer Flossen nicht nur an Land fortbewegen, sondern lassen sich (es gibt Experimente an Senegal-Flösselhechten) auch unter vorwiegend terrestrischen Bedingungen in Terrarien halten.

Erst innerhalb der echten Fische ist die Schwimmblase entstanden, die sich durch Evolution aus den Lungen heraus bildete. Die fachgerechte Beschreibung lautet daher: Lunge und Schwimmblase sind einander homologe Organe. Innerhalb der Actinopterygii gibt es einen evolutiven Trend, demzufolge die Schwimmblase bei urtümlicheren Vertretern (noch) der Atmung dient, bei evolutiv weiter abgeleiteten Vertretern hingegen nur noch die Funktion der Austarierung im Wasser übernimmt.

Allerdings ist es innerhalb der echten Fische oftmals schwierig zu entschlüsseln und noch immer Gegenstand phylogenetischer Studien, ob die Lungenfunktion einer Schwimmblase einen Hinweis auf Urtümlichkeit darstellt, oder ob sekundär aus einer Schwimmblase mit Tarierfunktion erneut ein Atmungsorgan entstanden ist. In der Evolutionsbiologie werden im Übrigen unabhängige Entwicklungsschritte stets als Konvergenzen bezeichnet.

 

Arapaima gigas veratmet mithilfe seiner Schwimmblase atmosphärische Luft

 

Auch Arapaima gigas ist ein Luftatmer, der auf den Einsatz seines zusätzlichen Atmungsorgans in Form einer Schwimmblase sogar angewiesen ist. Er ist ein obligater Schwimmblasenatmer, der atmosphärische Luft an der Wasseroberfläche mithilfe seiner Mundöffnung aufnehmen muss. Dies wird als Anpassung an den häufig sauerstoffarmen Lebensraum der Tiere interpretiert, die sich häufig in Überflutungszonen des Amazonasbeckens aufhalten, wo wenig im Wasser gelöster Sauerstoff zur Verfügung steht. Der Literatur zufolge muss Arapaima gigas alle fünf bis fünfzehn Minuten die Wasseroberfläche aufsuchen, um dort mit seinem oberständigen Maul Luft einzuschnappen.

 

Berlin, Februar 2019, copyrights Stefan F. Wirth