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During the Carboniferous period, global forests first appeared, covering tropical zones with tree-high horsetails, clubmosses, and ferns.
These were the first global forests, at least in tropical zones. They were originally interrupted by swamp-like areas and a correspondingly moist air. Especially horsetails and clubmosses could reach altitudes like modern trees. Correspondingly massive were their trunks, which not rarely were even preserved three dimensionally in bituminous coal fossils.
More oxygen, less free CO2 and a corresponding climatic change in the subsequent Permian period
Oxygen levels rose, and CO2 was bound for the transformation of sediments into peat, lignite and then bituminous coal. The climate presumably therefore increasingly became colder due to the decreasing greenhouse gas finally leading into the Permo-Carboniferous Ice Age period.
As in the Carboniferous, where conditions could temporarily change, for example due to floods creating even more layers of biomass, which subsequently was modified into peat, also the Permian was characterized by changes, creating an ice age period, which was no continuous time of cold, but interrupted by shorter warming periods.
Animals
Animals were mainly represented by (often) large arthropods, which benefited from the high oxygen levels for their unusual growth.
Arthropods breathe via a system of cuticular tracheas, through which oxygen is mostly transported via diffusion. A larger animal needs longer and wider tracheas to reach the internal organs, where gas exchange is required. This only works, when there is an especially high oxygen concentration available.
But also other taxa of Protostomia and Deuterostomia were present. Even represented by primeval tetrapods such as prehistoric amphibians and reptiles.
Fossil preservation in bituminous coal
Please find attached bituminous coal plant fossils from Saarland (Germany) from my collection. Bituminous coal is in greater quantities for example present in South-Western Germany, where coal mining was also an important economic factor until some decades ago. This coal is nothing else than fossilized remnants of Carboniferous forests. Complex and often intact appearing plant (and more rarely animal) remnants can be easily found, when you are interested in traces of prehistoric biodiversity and have some endurance to look for the good ones. Then you can find fern fronds, huge pieces of the trunks of tree-like horsetails or clubmosses. Often the root areas are preserved, as visible in one of my presented fossils.
An interesting ornamental plant genus, being even subject to scientific research
Plants of Peperomia belong to the pepper-related Piperaceae. Here, P. caperata is shown, a typical succulent with fleshy, water-storing leaves. In total, more than 1500 species are known, distributed in tropical and subtropical regions. E. Ji Shin et al. (2023) studied their effects of different white light color temperatures.
One citation of my literal narrative is: True beauty often lies hidden, more often than some would like to admit, those who present themselves as enlightened, even though they are actually quite blatantly concealing their true depravity with too much light.
Eun Ji Shin, Jae Hwan Lee, Sang Yong Nam. (2023). Changes in Growth, Visual Qualities, and Photosynthetic Parameters in Peperomia Species and Cultivars under Different Color Temperatures of White Lighting Conditions. Journal of Agricultural, Life and Environmental Sciences, 35(3), 307-321. https://doi.org/10.22698/jales.20230025
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Living on an arthropod cadaver and securing the access to it, when the arthropods is still alive, is a life-style named necromeny, which in specific mites evolutionarily derived from Phoresy/phoresis.
Phoresy in general, Phoresy in mites of the Histiostomatidae and necromeny derived from it
Phoresy is a strategy in which one organism uses another to transport itself. The benefit of this strategy is strongly skewed towards the so-called phoront, the partner being transported. However, the destination of the transport is often the nest of the transporter (for example of barkbeetles), at least when it comes to phoretic mites or nematodes. There, the phoronts can influence the microclimate, which can be advantageous or disadvantageous to the transporter. This is particularly true for mites of the Histiostomatidae (Astigmata). They are primarily fugivorous and carry their own fungal spores (hyperphoresy). Within the Histiostomatidae, another strategy has evolved from phoresy several times (apparently at least twice independently): necromeny, which will be explained in more detail here using the mite Histiostoma polypori and the earwig Forficula auricularia as examples.
Details about the life strategy phoresy
Life-strategies that closely connect two different organisms have long interested me in my scientific work on mites.
If mites, such as the Histiostomatidae (Astigmata, Acariformes), are phoretic, they will be transported to a new habitat in form of a special dispersal stage (deutonymph), when their old, ephemeral microhabitat is threatened by desiccation. In the new habitat, the transporter, usually an arthropod such as myriapods, spiders or insects, is abandoned, and the mites continue their development in the new substrate.
Necromeny and how/why it differs from phoresy
Another strategy, distinct from phoresy, is derived from this: necromeny. In the case of a necromenic mite, the ascent onto a transporter begins as in phoresy, but with the crucial difference that the habitat the mite needs for further development is the carcass of the transporter itself. It is important to note in this context that the mite does not cause the death of the necromenic transporter, but instead waits for its natural death.
The special case of mite Histiostoma polypori and earwig Forficula auricularia
In the case of the earwig Forficula auricularia, necromeny is even derived from the original necromenic procedure in that the mite Histiostoma polypori (Histiostomatidae) does not develop on the carcasses of adult female earwigs, even though these are the ones that carry the mites to their nests. Instead, the carcasses of young earwig nymphs that accumulate in the earwig’s nest due to natural mortality are the final habitat of this mite. This might be a hygienic benefit for the breeding earwig and its surviving brood. Subsequently mite deutonymphs attach to younger earwig nymphs and, as earwigs are hemimetabolous insects, switch during the earwig’s molting behavior onto the next nymphal developmental stage, which is reoeated until the earwig reaches adulthood.
In my scientific publication S. F. Wirth (2009), I report on the life strategy of the mite H. polypori. In my video S. F. Wirth (2015), I visualized these biological contexts again.
It is unknown, how often necromeny appears in the phylogenetic tree of the Histiostomatidae or even in the higher taxon Astigmata, as closer biological studies are often missing. If work about Histiostomatidae is performed, then mostly from a strict taxonomic point of view. Data then often are species lists or new species descriptions. This is a pity as most Histiostomatidae can be easily cultured, but which of course requires effort and some knowledge and experience about suitable climatic conditions in such tiny terraria.
I presume that necromeny might appear more often than only twice in Histiostomatidae, but studies are missing. And it is even unknown, whether there are species with an overlapping of both strategies, necromeny and phoresy, in which both, developing on the cadaver of its carrier or developing in its preferred substrate, are functioning options for may be the same mite species.
In the mite Histiostoma maritimum, which is mainly associated with beetles of the genus Heterocerus, necromeny is according to my studies (e.g. S.F. Wirth, PhD thesis 2004) the only strategy leading to a useful rearing success under culture conditions. In case of this mite the necromenic life-style corresponds to the most simple procedure as described in the general chapter above. Mite deutonymphs ascend their carriers, namely (at least) adult beetles, and never leave them, instead wait until their natural death to develop on their cadavers. I never reared the beetle, only the mites. Thus it is still unknown, whether the dispersal stage of the mite (deutonymph, in old publications also referred to as „hypopus“) only rides on adult beetles, or whether the beetle’s larvae or pupae play any role too. Pupae guarding can generally appear in phoretic Astigmata. For example in ants, see S.F. Wirth (2015, video) about ant Myrmica ruginodis and mite Forcellinia wasmanni (Acaridae, Astigmata).
Biological character traits of organisms on Earth are the result of evolution. Organism species form niches within their environment. Environmental selection factors favor certain randomly occurring combinations of traits, while other combinations are not favored and are therefore less frequently passed on to offspring generations. If an evolutionarily developed trait affects not only the species of concern but also another species, coevolution may have played a role. Coevolution can only occur if both species, which mutually influence each other evolutionarily, coexist over a longer period. A possible example is mimicry, in which another, more deterrent-looking species is imitated for self-protection. Such a mimicry is for example I the relationship between cheetah cubs and the honey badger.
Imitating the für of another species
The honey badger Mellivora capensis (Musteloidea, Caniformia) exhibits an unusual defensive behavior that even deters large predators from attacking it. Juvenile cheetahs Acinonyx jubatus (Felinae, Feliformia) mimic the typical appearance of the honey badger, specifically by developing a light-colored patch of greyish fur on their back that, as with the honey badger, contrasts sharply with the normal fur on their sides and bellies. This mimicry of a dangerous or particularly defensive animal to protect oneself from attack is known as protective mimicry. This context was for example reported in Eaton, R. L. (1976).
Mimicry is distinct from mimesis. The latter involves imitating not the appearance or behavior of another animal, but rather its environment. Mimesis can therefore also be described as visual (or tactile) camouflage.
Conditions that must be given that a selection pressure to a mimicry persists
Protective mimicry arose through selective pressure and evolution. Such selective pressure persists when the imitated animal actually inhabits the same environment. Mimicry is only beneficial if potential predators have had the opportunity to make negative experiences with the imitated animal. This condition is met in the case of the honey badger, which is mimicked by cheetah cubs. It is widespread in large parts of Africa and even occurs in parts of Asia. Cheetahs and honey badgers thus share their habitats, at least in sub-Saharan Africa. In Asia, only small, critically endangered remnant populations of cheetahs remained.
About the biology of the honey badger and its activity periods being more or less identical with the predators of cheetah cubs
The honey badger is similar in size and appearance to a European badger, but is not closest related to it within the Mustelidae. This solitary species feeds predatorily on mostly small vertebrates such as rodents, lizards, frogs, or bird eggs. It also ventures to prey on the young of larger animals. Honey badgers are often crepuscular and nocturnal, remaining hidden in underground burrows during the day. Cheetahs, on the other hand, are diurnal, so there is little overlap in their activity patterns. However, it is also much more important that the enemies of cheetahs, especially their cubs, are well aware of the honey badger and associate it with its formidable defenses. This is the case with the more nocturnal lions, leopards, or hyenas.
The honey badger defends itself fiercely, even against larger animals. Its extremely thick skin effectively resists bites. Its own bites, combined with its sharp claws, can inflict serious injuries on attackers. Furthermore, the animal can secrete a foul-smelling defensive fluid from its anal glands. A key factor in ensuring that leopards or lions who encounter a honey badger during their nocturnal forays have a negative memory of it is the honey badger’s aggressive nature, which can extend even to significantly larger animals. If one of these large, nocturnal predators encounters a leopard cub in low-light conditions, it may, under certain circumstances, leave it alone, namely if the cub’s resemblance to the honey badger appears too striking. This is despite the fact that the cheetah cub would otherwise be an easy prey.
About a videographic reference and my AI assisted illustrations
A video compilation to this topic from National Geographic (2026) is linked below. Motion pictures can sometimes highlight interesting and complex contexts better than words or still pictures.
My images I have included with this article are no photographs, but illustrations created with AI assistance.
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Despite our current awareness of species conservation and the importance of our biodiversity for maintaining the ecosystems we need to survive, species continue to go extinct. However, extinction events are not inherently a cause for concern. If two descendant species arise from a single ancestral species (steam species) through evolution, then that ancestral species is, by definition, extinct. This means that evolution and the extinction of species are inextricably linked. It happens constantly somewhere in the realm of living organisms and will only cease when the Earth no longer exists in its current form.
And yet, numerous extinction events of animals and plants can be attributed solely or primarily to humans.
These include large animal species that became extinct in modern times, such as the Tasmanian tiger (Thylacinus cynocephalus) or the dodo, which will be discussed in more detail here.
The dodo Raphus cucullatus (Columbidae), lived on Mauritius exclusively and was first discovered during a Dutch expedition in 1598. This flightless, ground-nesting bird died out by 1690 i.a. due to introduced predators, as it lacked defensive behavior. A research project aims to recreate it based on its and the genome of its closest living relative.
D. Angst et al. (2017) reconstructed ecological aspects from bone histology studies. The ground dwelling bird dodo, extinct by about 1690 on the island Mauritius had a size of about 1 meter, a weight of about 17 kg and a beak of 23 cm. The 2017 study above found due to bone morphology details that it was breeding in August and that chicks were fast growing to reach a larger size, before the austral summer began.
The dodo, which was found only on Mauritius, must therefore be classified as an endemic species. Endemic species are particularly vulnerable to changes in their ecosystems. They are generally highly threatened with extinction. In the case of the dodo, its demise was undoubtedly due to the fact that it had no natural predators to fear, and presumably no serious competitors for food. Consequently, it lacked effective defense mechanisms, although it has been reported that it occasionally used its distinctive beak in self-defense.
It was the domestic animals introduced by humans from around 1600 onwards, such as monkeys and pigs, that decimated the dodo population. Introduced rats also became detrimental to the dodo population. The aforementioned animal groups could act both as predators of the dodo, for example by eating its eggs and young, and as competitors for food. Unlike rats and domestic pigs, dodos were herbivores with a preference for fruit, such as palm fruit. They were therefore at a disadvantage compared to omnivores.
However, humans not only indirectly influenced the dodo’s extinction but also directly. They captured the birds, which offered no resistance, and used them as live food supplies on their voyages, even though their meat was not considered palatable.
Furthermore, recent discoveries have also provided evidence that a natural disaster further decimated parts of the dodo population.
Why would one want to „recreate“ the extinct dodo?
There are efforts underway to bring some extinct animal species back to life using genetic engineering. A prerequisite for this, of course, is the availability of genetic material. This is the case, for example, with mammoths, the thylacine (tasmanian tiger), and the dodo.
The company Colossal Biosciences, for instance, has announced plans to resurrect the dodo. But why all this? Naturally, the recreation of an extinct species is simply fascinating, arouses curiosity, and could therefore be commercialized. Science for its own sake also justifies many things that might seem surprising in terms of content, provided funding is secured. And that is often the case when a spectacular aspect is involved.
However, there are also sensible, practical reasons. For example, ecosystems and their biodiversity can benefit from a formerly native faunal element, which could thus support a better stabilization of the corresponding ecosystem. Furthermore, the activity of large, walking animals can stabilize the soil and keep carbon dioxide sources contained, which would benefit efforts toward greater climate neutrality in the face of global warming.This would, of course, apply particularly to mammoths.
Problems of recreating such species: according to current understanding, the animals produced would primarily have the genome of an extinct species. They would likely lack both instinctive behaviors and, even more so, those passed on to offspring through parent animals and other conspecifics.
My illustrations
Illustrations of extinct animals are common. Three-dimensional reconstructions are also plentiful. But depictions of the corresponding animals in their natural habitat are somewhat rarer, and when they are, they tend to appear, for example, in museum dioramas.
Animals in their natural environment—in this case, reconstructions of the animals and their environments—convey an ecological context and thus create the illusion that they are real animals, hopefully similar to those encountered in nature in the past.
Illustrations can be created analogously with paint and canvas. However, I also see interesting possibilities in the increasingly sophisticated use of AI for creating meaningful illustrations that can even be brought to life through animation using subsequently suitable further AI.
In the case of my dodo scenes, I worked with Adobe Firefly and generated images with cohesive scenes using detailed prompts and previously created sketches. For this, I also extensively researched the diversity of present-day landscapes on Mauritius through image research and satellite imagery. I then manually adjusted the resulting illustrations to my liking using editing software like Lightroom.
A robber fly with clearly visible, rhythmic breathing movements initially arouses the observer’s astonishment. After all, flies are insects, and insects breathe passively using a tracheal system through which oxygen-rich air diffuses to the organs inside their bodies. Well, not quite. Hemolymph pressure, for example, can cause the tracheae to move in subtle ways that go beyond mere diffusion. However, some insects also practice active breathing movements to make gas exchange more efficient. And these breathing movements are indeed clearly visible with suitable macro optics and are called convective ventilation.
About the relevance of video footage with animal behavior
Film recordings have traditionally been a suitable means of depicting animal behavior in its complete context, including all its gradual processes. However, they are not only suitable for illustrating behavioral characters, but also for scientific analysis. Video recordings are of especially high quality in the digital age. Digital processing with suitable software is relatively simple these days; the associated programs are efficient and serve either for video editing or even video image analysis. Thus, filmed animal behavior can serve as the basis for qualitative scientific studies, but with the help of specially developed scientific software, it can also enable quantitative behavioral studies, for example, when considering the use of drones to study the population dynamics of herd mammals. The film recordings I show here are primarily intended to illustrate the active breathing movements of a robber fly, which are difficult to detect with the naked eye.
What is a tracheal system and how does it generally work? Some basic information
What exactly is a tracheal system, and how did it evolve? And why don’t insects breathe like terrestrial vertebrates do? Well, insects are arthropods. Unlike vertebrates, they don’t have a bony inner skeleton, but rather a chitinous outer skeleton. Whenever an arthropod requires solid structures inside its body, these must be made of chitinous cuticle and have been relocated from the outside to the inside during early development. This applies to muscle attachment sites, so-called apodemes, as well as the internal respiratory system, the tracheae. Tracheae begin with an outward-facing spiracle opening, from which a spiracle branch connects inward, which ultimately connects to longitudinal tracheal branches and branches out finely toward the different organs and tissues. Is this always the same principle for all arthropods? In principle, yes; But the structure and course of the tracheal system differ in detail between different arthropod groups. This is because the principle functions similarly due to evolutionary constraints, but cannot be traced back to a single evolutionary event. Tracheae have evolved multiple times within the Arthropoda.
The robber fly Tolmerus cingulatus and about the energy consuming hunting behavior of robber flies (Asilidae)
The robber fly Tolmerus cingulatus (Asilidae, Diptera) can frequently be observed in Berlin. Its strength lies not in a long, sustained, and energy-efficient flight, but in the opposite. As an ambush predator, the robber fly observes its surroundings from a prominent position. Suitable prey are usually flying #insects, which the robber fly captures in a rapid, targeted, and precise sprint flight, efficiently grasping them with spiny leg segments and spiny, forward-facing bristles.
This requires strength and precision and is therefore particularly energy-intensive. While resting, in this case perched on my sun-exposed windowsill, it supported more efficient gas exchange through convective ventilation. At the same time, the thermoregulation effect prevented its body from overheating.
Convective ventilation and its context with thermoregulation and a scientific research paper about the complexity of breath control in insects
Breathing movements, known as convective ventilation, actively support gas exchange, for example, by opening the spiracles further. Such breathing movements are necessary and helpful when an insect has to perform a particularly energetically demanding task. The resulting accelerated air exchange also achieves thermoregulation, which prevents the insect from being harmed by excessive heat, what the fly had to deal with in my windowsill.
The authors E. Gefen (2021) studied detailed aspects of the complex motor activity connected with insect gas exchange patterns, which also includes central and peripheral chemoreception.
My YouTube Video about T. cingulatus performing convective ventilation
Please watch and also like my new YouTube video about convective ventilation of a robber fly:
Eran Gefen, Philip GD Matthews, From chemoreception to regulation: filling the gaps in understanding how insects control gas exchange, Current Opinion in Insect Science, Volume 48, 2021, Pages 26-31, ISSN 2214-5745,https://doi.org/10.1016/j.cois.2021.08.001
Whether solar or lunar eclipses, the latest results from space missions, or the thought that humans will one day travel into space the way we travel on Earth today, everything requires the latest technological advancements. And yet all of this is also directly connected to our past. For we ask ourselves how carbon, the basic building block of life on Earth, even came to be on Earth. Perhaps through asteroids that hit Earth? What do we know about the time of the formation of our solar system? At least we know that comets have something to do with it. That’s why it’s always around then when the news is announced that a comet will soon be visible to everyone from Earth. Anyone who is interested can catch a glimpse of a witness to the formation of our solar system. Comet Lemmon is one of the most recent examples of this.
Short introduction about comet Comet C/2025 A6 (Lemmon) seen from Berlin
Comet C/2025 A6 (Lemmon) was only discovered at the beginning of 2025. On October 21, 2025, it made its closest approach to Earth and, according to forecasts, should even have been visible to the naked eye. However, the sky was too cloudy, so I only had the photos from the previous day, when I shot the comet shortly before sunrise around 5:34 a.m. With the help of a starry sky app and thanks to very clear skies, I was able to locate it from Berlin, although it was hardly to see with the naked eye.
General Information about the composition of a comet
Comets are remnants from the time of the formation of our solar system. The structure of a comet can be simply divided into the cometary nucleus and the surrounding coma. Both together are called the cometary head, and both are visually distinguishable from the cometary tail, which only forms when the comet is within the sphere of influence of the sun. A comet is essentially a body of ice, dust, rock, and gases. Solar wind and radiation pressure stir up components of the coma and displace them outward. A cometary tail can reach a length of several hundred million kilometers, which is remarkable considering that the nucleus is only a few kilometers in diameter.
Comets and asteroids
Comets originate from the outer reaches of our star system. Only there is the necessary cold for carbon and hydrogen compounds to phase-transform into ice. In general, it can be said that comets are often difficult to distinguish from asteroids. Therefore, the characterization of a comet is often more comprehensive today than before. According to this theory, a comet is any icy minor planet. This is based on theories that some asteroids actually have a cometary nucleus.
Periodic and non periodic comets
Comets are usually divided into periodic and aperiodic. Periodic comets have orbits around the Sun that allow them to return to a certain area related to the earth regularly, making them visible again at specific intervals. Aperiodic comets, in contrast, move in hypebolic or parabolic orbits and either do not return, or the determination of their trajectory has not yet been reconstructed.
About the comet Lemmon, its discovery and my simple sky observations in mid October 2025
Comet C/2025 A6 (Lemmon) is considered non-periodic. It was discovered on January 3, 2025, by the Mount Lemmon Survey, which uses a Cassegrain reflector telescope for its observations. On October 21, 2025, the comet reached its closest position to Earth. On that day, however, the cloud cover in Berlin was so dense that a clear view of the starry sky was impossible. However, I did make simple observations early in the morning of October 20. Using the Stellarium app, I determined the comet’s position in the late night sky at about 5:34 am. At that time, the comet was located approximately centrally well below the constellations Ursa Major and Canes Venatici. More precisely, it was the „third position“ below the star 25 Canum Venaticorum. I used the night mode on my very high-resolution smartphone camera and was only able to locate the comet (seemingly) correctly in the photos by digitally zooming in and with some effort. It was located just above a house, and I almost mistook it for another rooflight, as one was visible not far away. Zooming in even further produced a correspondingly greater blur. However, the tail, pointing to the left in the image, still seems to be only very faintly visible, which corresponds to the image in the app I used as a template.
About a scientific paper about comets as witnesses of the formation of our solar system
In their preface article, scientific authors K. E. Mandt et al. (2015) examine comets as witnesses to the formation of our solar system. A crucial development leading to a better understanding of comets was the discovery of probe missions that, since the mid-1980s, have approached comets at close distances to collect data on the structure of these large, dusty ice balls. To date, precise measurements of the structure of the coma and the comet’s tail have been obtained. This article summarizes basic information on this topic. This concerns, among other things, the question of what role the solar wind plays in the formation of cometary coma and cometary tail.
On the harvestman Odiellus spinosus (Phalangiidae, Opiliones, Arachnida, Chelicerata), which is native to southern Europe but is increasingly spreading northward and can be found, for example, in Berlin. On its morphology and biology, on its expansion trends from its native territories, and about its first record in Poland.
Berlin as a German hotspot for O. spinosus populations
Odiellus spinosus was originally widespread in Southern Europe, but has now also become native to Western and Central Europe, with a trend toward Eastern Europe. The species appears to be benefiting from global warming. In Germany, the harvestman is not widespread, but rather in island-like areas of the country with warmer, climatically favorable conditions. The region around Berlin is a hotspot.
Distinctive morphological characters
The species is morphologically clearly distinguishable from other native or invasive harvestmen in Germany. Only it has three horn-shaped spikes in front of the eyes. With a body length of approximately 10 mm in females, O. spinosus is a rather large species. In comparison, the legs appear quite short, which gives the harvestman a stocky appearance. A clear saddle stain on the backside of the opisthosoma is also an important taxonomic character to identify this invasive species. O. spinosus is active as an adult from July to December and can be found in forests, where it prefers dry and warm conditions. I found the individual in my photo series under the bark of a dead tree trunk in Berlin in October 2025 and photographed it there on site. The harvestman can also occur synanthropically near human dwellings.
Global warming facilitated the establishment of numerous southern European species in the area of Berlin
Various animal species that originally occur in the Mediterranean/southern European region have spread to Berlin either independently (biological colonization) or through human intervention (invasion = neozoa). I have documented several such species photographically:
About the spread of O. spinosus in Belgium and about the role of citizen science
In their study, the authors S. Van de Poel et al. (2021) examined the spread of O. spinosus in Belgium. It was known that the species had reached Western Europe and Belgium since around 1990. A sufficiently large amount of data on the current distribution of the harvestman was only possible through the use of citizen science data, primarily provided by the free app. Obsidentify, which uses AI to identify species based on photographs. Thus, even laypeople with little biological experience were able to correctly identify this rather large harvestman.
Because the increase in data on the current distribution of O. spinosus coincides with the availability of certain identification tools such as Obsidentify, the actual history of the increasing rate of the species‘ spread in Belgium remains unknown. However, a drastic increase in the harvestman’s population density is discovered.
Introduced to Western and Central Europe by itself or by human transport?
There is multiple literature indicating that the harvestman O. spinosus must be named a neozoon or an invasive species and not a result of biological colonization, as the species did not disperse over these great distances by itself, but was, at least originally, introduced with human traffic.. Harvestmen, as non-flying arthropods, have less potential to spread independently over remarkable distances than, for example, flying insects. The authors of the paper above also infer that human introduction originally enabled the colonization of Western and Central Europe, for example, when they point to localities with new specimen findings that they interpret as the direct result of human introduction without the species indeed being already permanently established at these new areas.
Easternmost finding was in 2010 Poland
The authors R. Rozwałka & P. Sienkiewicz (2010) summarize the early spread history of O. spinosus to Western, Central, and Eastern Europe and place the first findings outside its original distribution area already starting in the 1970s. They name the first finding of the harvestman in Poland as the easternmost record in Central Europe of the species, which was discovered in the Warta River valley near Mosina.
The firebug Pyrrhocoris apterus (Pentatomorpha, Heteroptera) is a well-known insect in Germany, due to its strong aggregation behavior and its striking color pattern. Unfortunately, it is often called the „Feuerkäfer (fire beetle)“ in Germany and thus confused with a beetle (Coleoptera). The species exhibits an interesting dimorphism in its wing shape. Dimorphism here just means distinctly differently shaped.
Long-winged and short-winged and distinct personality differences
Pyrrhocoris apterus is distributed across parts of the Palaearctic with northward trend. Most individuals are short-winged (brachypterous), only 5% long-winged (macropterous). With few exceptions, all are flightless, but differ in their life-histories. E. Gyuris et al. (2010) found differing individual behaviors (personalities) with females of the long-winged morph being „braver and more exploratory.“
According to the literature, reports of flight-capable long-winged specimens are anecdotal in nature, and precise studies seem to be lacking. However, there are suggestions that flight-capable forms may have played a role in the northeastern expansion of the species‘ range. However, even independent of flight capability, macropterous forms are thought to play an important role in the species‘ dispersal trends due to their life histories differing from the short-winged forms.
biologe 