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Locomotion behavior of Schizomida (Arachnida)

They look without magnification more like very motile and fast running ants or very tiny grasshoppers than like arachnids. But they indeed represent relatives of the web spiders and scorpions: Schizomida, a clade of whip scorpions. They are the sister taxon of Thelyphonida, the rather well known „big whip scorpions“, which are often kept as pets in terraria around the world. Schizomida are only rarely filmed in a higher resolution quality, which is due to their small size and their almost invisibility due to their semi-transparent cuticle and their very fast way of walking or even jumping. They are additionally difficult to be filmed as they strictly avoid all lights and tend to dry out quickly, when they cannot hide themselves by time in a slightly moist substrate.

 

Closeups of behaviors of a Schizomid species from a greenhouse in Germany. Copyrights Stefan F. Wirth

 

Schizomida in Greenhouses

 

Schizomids represent mostly tropical or subtropical organisms. But some species are regularly dispersed into greenhouses around the world. The filmed species might be Stenochrus portoricensis, but was not systematically studied in detail so far. As all known species, which appear in greenhouses, also S. portoricensis reproduces (apart from their original habitats) parthenogenetically with females producing females without mating procedures (thelytoky). I never found males so far.

 

 S. portoricensis: native to subtropical Zones

 

The specimens, which I kept since months in a small terrarium, were collected in autumn 2016 at the famous fun and wellness bath „Tropical Islands“ South of Berlin. There they are a natural part of the world’s biggest indoor rainforest. The species S. portoricensis is originally native to Florida, Mexico, Cuba, Nicaragua, Porto Rico and other localities in similar tropical zones. These microscopical tiny organisms are predators and do not harm human beings at all. According to the available organisms in a suitable size in my terrarium, they might feed on the numerous collembolans and/or mites. Especially mites of the Gamasina appear in greater numbers in my substrate, which represents the original substrate from the greenhouse. I enriched this substrate regularly by smaller pieces of fruits or vegetables to stimulate the growth of microorganisms. I keep them at room temperature (about 20°C) and with not too much moisture. I do not know, whether they reproduced within these months, but the specimens of my recent video footage represent all sub-adults.

 

Film set and topic locomotion

 

Focus of my film is to present the different ways of locomotion, cleaning behaviors and burrowing activities of these fascinating animals. During the filming procedure, I used two cold-light-lamps for a suitable illumination and an ILCE-6300 (internal 4K mode), connected to a stereomicroscope and a lightmicroscope (with uplight).

 

Berlin December 2019/ March 2017, Copyrights Stefan F. Wirth

When elbows are used in the world of science

I was part as acarologist and natural scientist in a 2011 scientific paper about a mite preserved as fossil in amber, which was analyzed using the X-ray computed tomography and determined systematically on a family level. In this time, this scientific publication had a remarkable impact in international scientific media, because it seemed, as if this mite was the smallest animal ever visualized via CT on a high quality level.

 

Strange behaviors of so called „colleagues“?

 

The technical work was performed by technical scientists in Manchester UK. The natural scientific analyses was performed by me as the only European specialist for the mite family Histiostomatidae. But I noticed already in the time period of  this publication that there were strict tendencies by the so called „colleagues“ to mention my name as less as possible, this concerned the drafting of international media releases and also a poster presentation (my name was added days later) and an online abstract on a conference in Berlin. The corresponding poster was even awarded, but I got my award certification only after demanding explicitly for it. I much later, when I decided to complain officially at the Museum of Natural Sciences in Berlin, needed to learn that I was not even considered as one of the first authors. I didn’t notice that before, because the former „colleague“, Dr. Jason Dunlop, curator at this museum, was mentioned in the original citation with 1) after his name, me too. Thus I interpreted this as a double-first-author-ship. It then came out that the „1)“ only indicated the same scientific address, because I was in that time officially a volunteer at the MFN in Berlin.

 

Mite in an amber fossil, made visible by using the x-ray computed tomography, acarological work: Stefan F. Wirth

 

The work of a scientific specialist: here an acarologist

 

The question must be: Who is needed to scientifically interpret three dimensional photos of an amber fossil, in this case the deutonymph of a mite of the Histiostomatidae? A specialist for this taxon is needed, who is able to perform scientific drawings, based on the photos. He first needs even to decide, which of the photos are showing details of scientific relevance. While drawing, the specialist must distinctly recognize single microscopic structures, so that all these structures can be clearly separated from each other including all borders or gaps between single components. The scientific term is „homologisation“. Homologisation means: comparing single structures with (phylogenetically) equivalent structures of other (related) species. As there were not more fossils available, the homologisations needed to be based on recent mites. Thus the specialist must have a very competent knowledge of a high number of species from this family. To reach that level requires hard work over many years. I had the necessary level and found character details in the fossil, which were fitting to recent members of mites of the Histiostomatidae. But it’s of course not enough to discover such homologous structures. They must be made visible for every reader of the scientific paper. Thus the drawings need to be correctly labelled, which requires careful morphological studies. Then a detailed description needs to be written. But that is far not enough. Readers of a scientific paper are usually no specialists. That’s why they need a written introduction, in which the summary of the general recent knowledge of a mite group needs to be presented. And after all that they even expect you to discuss your results. It’s an own chapter, subsequent to the result descriptions.

The discussion chapter also requires a maximum of specialized competence. Some researchers even say that this is the first part of a paper that they read as it puts the results into a general scientific context based on arguments, mostly according to the principle of the most economical explication. Conclusions in the discussion part have usually the character of theories based on the facts, which the paper could contribute. Topics of a discussion part in such a paper as ours are systematic conclusions, the discussing of homologisation problems and also the formulation of a possible relevance for the recent scientific knowledge and also the future scientific importance of these new findings.

This all is, what I as a specialist needed to do. I additionally contributed one of my photos of a recent mite for comparative reasons and captured a stereomicroscopic photo of the mite fossil to demonstrate, how much the CT could improve the visible details of the amber fossil. I guess I did quite a lot, the other part was overtaken by the technical colleagues in Manchester. They needed to explain their technical situation and also needed to discuss their ideas about the meaning of their CT-technology for the future of science, focussed also on work with amber fossils.

 

Contributions of different authors to a scientific paper

 

To be honest I don’t remember, where there was still space left for content issue contributions by Dr. Dunlop. But he did some organizational stuff, he collected the contributions from the UK colleagues and me, he arranged the photo table via a graphic software based on the photos, which I had determined as scientifically relevant, and he was the so called corresponding author (I allowed him, because he is an English native speaker). That means, he submitted the final paper to the journal and communicated with the editors. Of course reviewers always ask for revisions. That was then mine and the technicians job again.

It is common that corresponding authors represent automatically the first authors of a paper. But it is not mandatory. I for example once was the corresponding author of a paper, which was based on a bachelor thesis that I (in major parts) supervised. I despite of my in fact major authorship regarding the scientific paper itself and my additional corresponding activities let her (the student) the first authorship. That even means that this paper can be easier found, when searching for her instead of my name. I just wanted to support a younger scientist.

And of course also a double first-authorship might be possible, especially representing  an adequate solution, in case another author even contributed more concerning the scientific content itself. In case of objections by the editors, the one, who contributed more, should to be the first author.

 

„B-word“?

 

But to come back to the amber paper of this article, it is surely not fair to reduce the scientist, who had the major scientific work on a paper secretly to a second author. It is highly unfair to leave him out in the international press release information. And I don’t trust to say here, what it is, when deleting his name entirely from a poster and an online abstract presentation and even impeding him to get a certification of a poster award in time for his work. Should one use the „b-word“? Generally bullying would be an act against the good scientific practice, but there would be clear proofs for malevolence against specifically somebody needed to get corresponding behaviors sanctioned. But when „only“ the elbow mentality is obvious, which means that people leave somebody out for their own better recognition, then the distinct malevolence against the victim is not clearly proven. Thus the interesting question arises: when is elbow behavior equal to bullying and when not?

 

Warning to young scientists

 

What I can say for sure is, even when the original bullying assumption is still a kind of questionable: after you complained, you might need to expect a real merciless and long lasting bullying. That’s why I intend to warn all young scientists: be careful and double check, with whom you cooperate. The wrong choice can be a failure as long as you do not agree being a bullying victim. The consequences can last over years and can destroy your whole career. I even once was told by a bullying victim that the accused institution did not even deny its bullying activities, but stated that depending of the kind of position, somebody has in an institute, an equality right would not be automatically existent. I go further and say: don’t become a natural scientist at all, except you are in a love relationship with an internationally highly influential professor.

In these days there are alternatives for possible natural scientists. Earlier I was a harsh critic of the modern gender sciences (sometimes also named genderism). But they have much financial capacities. Nobody there needs to sharpen his elbows, a good basis for fair careers, and based on that after a while surely also the most important basis for a good quality work!

 

Copyrights Stefan F. Wirth, Berlin 2019

 

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.

 

 

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

 

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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!).

 

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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

 

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

Mite Histiostoma sp., putatively new species, from mud around ponds (Berlin) and its morphology

Gravel pit area „Im Jagen 86“ in Berlin as biotope

 

„Im Jagen 86“ is a former gravel pit area in the Berlin urban forest Grunewald. It today represents a dynamic biotope, consisting of different types of habitats: mud around ponds, sand dunes, dry grassland and forest. Since the early 2000th, its habitat composition partly changed remarkably. Out of several (smaller) ponds, only one bigger pond remained. All ponds originally were surrounded by sapropel, a habitat for different interesting organisms, such as beetles of Heterocerus, Elaphrus and Bembidion. The mite Histiostoma maritimum was commonly found phoreticaly on Heterocerus and Elaphrus. I additionally in those early 2000th described the new mite Histiostoma palustre from Hydrophilidae of Cercyon and Coelostoma, living inside the saporopel as well. Today only a few small areas with open sapropel exist. I so far did not look for Histiostoma maritimum again and don’t know, how common it still is. At least Heterocerus beetles are harder to find than in earlier years. I so far did not found Histiostoma palustre again.

 

Rearing conditions of a putatively new mite species

 

I collected new mud samples in March 2019 at different areas, but found developing histiostomatid mites in a sample from the edge between mud (sapropel) and mosses. It is a species I never found before there and which might represent a new species. Only females could be morphologically studied. Nymyphal stages (not deutonymphs) are only available as video footage. No males were found. I had added bigger potato pieces to stimulate microorganism growth as mite food into the soil sample (room temperature). After about one month, a few mites (females and proto/tritonymphs) developed on only one of these potato pieces and quickly died out shortly after my filming activities and after I could prepare a few females. I actually try to get them reared again. Due to the low temperatures in March, it is considered that these mites hibernate independently from insects in the substrate. No bigger insects could be found in the substrate, which might be the corresponding carriers. But different dipterans (e.g. Ceratopogonidae) developed, they had no mite deutonymphs after hatching in my sample.

 

 

 

 

Morphological reconstruction of females and important characters as well as behavioral observations

 

The females of Histiostoma sp. differ from other females, which I know, by the mosaic of the following characters: body conspicuously elongated with a distinctly big distance between hind ringorgans and anus, digitus fixus almost simple shaped, fringes or ridges on palparmembrane, 6 dorsal humps, unusually big copulation opening. Leg setation not yet studied. One pair of ventral setae hardly visible (not in the drawing). Nymphs were observed during burrowing activities (footage), females are may be also able to. Deutonymphs or males would be useful to decide, whether the species is new. Some species are only described by deutonymphs.

 

Berlin, March/ June 2019 All copyrights Stefan F. Wirth

Ancient villa of Pollius Felix in Sorrento/ Italy: a nature refuge

Ancient ruins around the Gulf of Naples

 

The area of the Gulf of Naples (Italy) is full of ancient Roman ruins. Besides famous excavation sites such as Pompeii or Herculaneum, also not so famous, but nevertheless very fascinating buildings from around the first century are preserved. An example is the (originally) huge villa of Pollius Felix nearby Sorrento.

 

Pollius Felix and his eccentric extended villa in Sorrento

 

Pollius Felix was a rich man and build several villas around the Gulf of Naples. But the one nearby Sorrento surely was his biggest and most eccentric domicil. He intended to unite the four elements water (sea), air, earth (rocks) and fire (artificial heating system? lava rocks?) in his architecture. Unfortunately only a part of the very extended villa is preserved. But impressively shows, how the Mediterranean Sea was made to a part of a private building. What the natives call „I Bagni della Regina Giovanna“ is a sea water bassin (may be of natural origin) that was connected via stairs and bridges with the ancient super house. A reconstruction of the whole villa by the way can be seen in the second floor of the Georges Vallet Archeological museum.

 

 

 

How to visit the ruins?

 

The ruins are accessible for free, but visitors need to have good walking and climbing conditions. First an about 20 minuts walk downwards to the sea through an old tight walkway is required. To access the major parts of the ruins themselves small pathways through mediterranean seaside vegetation is necessary. The sea water bassin can be reached via stairs. In summer, it is a popular place for (mostly native) swimmers.

 

Landscape and biodiversity

 

The whole area is covered with natural wild vegetation, private and non private gardens and olive groves. A remarkable biodiversity is present, and – depending from the season – alwas shows different faces. In spring, early summer and autumn, everything is greening and blooming, while in the hot summer season drought predominates. The area is a home for interesting Opiliones (harvestmen), Diplopodes, rose chafers, snails or lizards (Podarcis) and snakes (rarely). I visited „Villa Pollio Felice“ (also named Villa Limona) this time in spring/ early summer: April 2019. Unlike in autumn, when I mostl visited the Gulf of Naples in the past, different flowers covered the region. The most abundant species was Allium triquetrum, decorating lush meadows with their almost bell-shaped white blossoms.

 

Villa Pollio Felice/ 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

 

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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.

Mite Histiostoma sachsi (Astigmata): Juvenile dispersal instar deutonymph and its orientation behavior

Some animals live in environments, where there is (almost) no light available. It makes no sense to see in the dark, but it is important for a specimen to know, where it actually is, where it is going to, whether there is enough food and what the conspecifics are doing. Predators need to be recognized in time, and a sexual partner must be found. There is also need for an efficient communication between specimens of a species. How can all this be performed by mites of the Astigmata, which usually live inside decomposing soil habitats in a more or less permanent darkness?

 

Olfactory sense organs in mites of the Histiostomatidae

 

Histiostoma sachsi (Histiostomatidae, Astigmata) is such a mite, living inside cow dung or compost. It might have a rudimentary ability for a light perception, but has not visible or functional eyes. It cannot produce any sounds. It can only feel and smell. Seemingly very limited abilities, but the contrary is fact: Due to evolution this mite is perfectly adapted to its life-style. It can feel objects by touching on them using its body setation (= body hairs). And it smells by means of very specialized body hairs, which are called solenidia and appear in different types, shapes and functions. These mites don’t smell on the level of us humans, which would be very insufficient. If at all, it should be compared with a dog. I am always fascinated when seeing blind dogs and how perfectly they can interact with their environment, despite their handicap. That’s may be how the efficiency of olfactory perception abilities of such a mite must be imagined. They do not only perceive scent particles from other animals, plants and soil components. Even olfactory signals from their conspecifics will be correctly and differentiatedly interpreted. And that not only marginally.  Olfactory signals represent indeed the major mode of their intraspecific communication.

 

Chemical communication of mites of the Histiostomatidae

 

Communication always requires contributions from both sides, a signal and an answer. These mites smell the signal of a conspecific using their solenidia, and they answer by the secretion of biochemical components. For these purposes, they possess a huge and complex gland system located on the upperside of their backs. Volatile excretions aggregate inside a big and rounded reservoir and finally leak to the outside via a pore, called oilgland opening. These gland systems are located symmetrically on both sides, each with one reservoir and one pore.

The meaning of the sent volatile message simply depends on the composition of the correspondingbiochemical components. Even diffferent stereochemical configurations of the same molecule can have different meanings. Citral for instance is a major component and has in different stereoisomers different functions. Such cummunicative volatile signals are usually named pheromones. And mites of the Histiostomatidae can indeed produce different kinds of pheromnes via the same gland system. Aggregation pheromones inform specimens about a suitable place to stay together with their conspecifics, for example due to a sufficient amount of food resources. Alarm pheromones solicit mites nearby to flee from an unpleasant situation. Sexual pheromones attract adult partners to each other in order to perform the mating procedure. But the gland secretions can even more. As allomones, they communicate with specimens of other species. They function as defenses against predators or other dangerous cohabitants.

 

Deutonymphs need to find a carrier for dispersal

 

Another form of communicative interspecific interactions is performed by a specific juvenile instar, the deutonymph. It looks morphologically quite different from all other instars (heteromorphic situation), does not need or possess a functional mouth, has a thicker cuticle as protection against drying out and a complex sucker organ on its underside in order to attach itself to an insect or another bigger arthropod. Deutonymphs of the astigmatid mites search for bigger carrier-arthropods to get carried from one habitat to another (dispersal strategy  is calledphoresy). While doing so, they again use their specifically modified leg setation (hairs) on the first pairs of legs to perceive scents for the detection of a suitable and passing by carrier. Basically it is still unknown, whether the term „communication“ is indeed appropriate in this context as we don’t know yet about a mutual interaction between deutonymphs and their carriers, before the phoretic ride begins.

 

 

Olfactory orientation of the deutonymph of Histiostoma sachsi, copyrights Stefan F. Wirth, February 2019.

 

Specific way of walking in deutonymphs

 

In detail, different kinds of behaviors can be observed in deutonymphs, when searching a carrier. The detailed behavioral patterns in this context can slightly differ between even closer related species. Deutonymphs of Histiostoma sachsi as all deutonymphs show a characteristic mode of walking, in which especially the first pair of legs plays an important role. During each step, performed by four pairs of legs, the first legs are lifted up much higher than all other hind legs. While doing so, they slightly tremble up and down. A behavior that mostly supports a better basic orientation inside a „jungle-„micro-landscape, being filled up with soil particles and decomposing plant tissues. But what H. sachsi deutonymphs additionally need in order to find their carriers is repeatedly to rest between the walking activities. Thus the first legs, which normally are still walking legs, are made free and that way available for the perception of carrier-scent-components only. These  namely are the legs that bear the highest densiy of solenidia.

 

Two different behavioral modes for an efficient orientation towards a carrier

 

Two different modes of resting with olfactory searching activities could be observed: In periodic intervals the deutonymph attached to the ground by using its sucking structures. They were then more or less laying on their entire undersides with only their forebodies slightly lifted up. By alternating moving the first legs up and down, olfactory information could be perceived from all directions without having the own body as a barrier to backwards. To improve its orientation situation, the deutonymph additionally turned on its own axis around, being stabilized by its sucking structures, which are flexible enough to follow these movements. When the deutonymph intended to continue its walk, it first needed to detach from the ground, which happened via muscle contractions that caused an abrupt detachment of the corresponding suckers. But main aim of the deutonymph is to find an elevated place, where the probability of a passing by carrier is especially high and from where a bigger insect (or other arthropod) can easier be ascended. There the second behavioral mode was performed. The deutonymph only fixed the edge of its hind body to the ground, again using the suckers on its underside, which are located close to this edge. This time the entire mite body stood in an upright position. The first legs again „waved“ alternating up and down and could under these especially elevated conditions even perceive scents from bigger distances. By occasionally slightly and alternating turning their upright bodies to both sides, olfactory information could be easier detected from all directions.

 

Carrier of H. sachsi still unknown

 

The frequency of such movements in mites increases typically as closer a suitable carrier approaches. But this was not yet observed or documented for Histiostoma sachsi. Its carrier inside the compost substrate is still unknown, which is why I so far could’t perform corresponding experiments. The species‘ describer, Scheucher (1957), found her mite specimens in cow dung and also didn’t identify the corresponding carriers there.

The observations presented in my video are part of my research project about morphologies and behaviors of deutonymphs in the Histiostomatidae.

 

Berlin, February 2019. All copyrights Stefan F. Wirth.