lemon tree Citrus × limon (Rutaceae) and its fruits, the insecticidal and antibacterial effect of the latter, about endophytic organisms and the fallen and rotting fruits as a microhabitat for phoretic mites

About the lemon tree Citrus × limon (Rutaceae) and its fruits, the insecticidal and antibacterial effect of the latter, about endophytic microbiota and the fallen and rotting fruit as a small habitat for phoretic mites (Histiostomatidae, Astigmata).

About the origin of lemon trees

The lemon is a hybrid of bitter orange (Citrus × aurantium) and citron (Citrus medica). It is unknown when the lemon was first cultivated. Some researchers place the origin of the lemon in ancient times. But wall paintings from the ancient Roman city may actually depict the citron. Presumably originally from India, it can be proven with certainty that the lemon reached southern Europe as a cultivated plant in the 13th century, where it was first cultivated in Sicily and Spain.

Morphology of flowers and fruits

The lemon flowers can be formed all year round and consist of five free petals and have 20-40 stamens that are fused together in groups. The fruits, which are on the tree at the same time, consist of up to ten segments that are interspersed with so-called juice tubes, which must be botanically referred to as emergences because different tissue areas are involved in their formation.

Lemon trees as species communities and about endophytic microbiota that a transmitted via the seeds

Like other trees, lemon trees are not just an individual plant, but a complex species community that contains a variety of micro habitats for a wide variety of organisms. The root system, the leaf system, the bark, the shoot endosphere, organisms live everywhere, mainly from taxa of bacteria, fungi, but also mites, nematodes and insects.
Organisms found inside a living plant can enter either through the roots, through injuries to the plant body or through natural openings such as in the area of the leaves. But how else can endophytic organisms get into the plant? The authors T. Faddetta et al. (2021) for the first time looked at the endophytic microbiota on Citrus x limon that enter the new plant via the seeds of the mother tree.
The researchers isolated fungi of the genera Aspergillus, Quambalaria and Bjerkandera and bacteria of the genus Staphylococcus directly from the lemon seeds. The following taxa were also identified by DNA sequencing from sprouts from externally sterilized seeds and the seeds themselves: Cutibacterium and Acinetobacter as particularly common representatives of the bacteria, Cladosporium and Debaryomyces as the most conspicuous fungal representatives.

Beneficial aspects of endophytes for the plant and hypotheses about coevolution

According to the authors, the biological role of the endophytes mentioned has not yet been sufficiently clarified. However, there is evidence that some of the endophytes are beneficial for the establishment of the young tree by promoting growth and inhibiting pathogens. Growth is promoted through the release of plant growth-promoting (PGP) factors. These can be, for example, acetoin, indoleacetic acid (IAA) or 1-aminocyclopropane-1-carboxylate deaminase, which can increase the solubility of phosphates and support nitrogen binding, thereby optimizing the metabolism of the lemon plant. The authors therefore assume that there may be a coevolution of the lemon with its endophytes, as selection pressure is conceivable that favored the vertical transfer of pathogens from the mother plant to the next generation. The authors also assume that endophytes have the ability to suppress plant pathogens. In general, the endophytes could help the young lemon tree cope better with adverse environmental conditions.

Defensive compounds of the fruits, a decomposing fungus and about the biological importance of decomposition

The fruit that is still ripening on the tree chemically protects itself from parasite infestation. The juice tubes inside the lemon are acidic, the peel contains bitter substances and an oil that contains i.a. the insecticidal substance citral. In particular, the fungus Penicillium digitatum (Eurotiales, Ascomycota), which regularly occurs on lemon plantations, is considered to be an important primary destruent of ripening and fallen fruits. It seems to have tolerance to the fruit’s defensive substances. The acids and oils of the lemon are a hurdle for numerous other organisms that normally decompose fallen fruits quickly. This applies to insects, but also to mites and various fungi, for example. Since the decomposition process of organic substances and the organisms involved are of fundamental biological interest, and since the return of free nutrients to the soil and the biogeochemical cycle is also of applied interest, I will discuss my own acarological research approach in the last chapter of this blog article. First, the chemistry of the lemon fruit should be introduced in more detail.

Major components in plant parts of lemon trees

The authors R. Hartati et al. (2021) deal with the phytochemically active substances in the various plant parts of the lemon tree in the form of a comprehensive literature research. They also deal with the multiple spectrums of action of these substances in the pharmacological spectrum. Active ingredients of the lemon plant can, for example, be divided into flavanones, flavones, flavonols, and terpenoids such as limonene, carotenoids and limonoids. For example, flavones can have an anti-cancer, antioxidant or anti-inflammatory effect on the human organism. They have in the plant tissue an antibacterial and fungicide effect.

Returning of nutrients into the biogeochemical cycle and the connection with mites and other decomposing organisms

In connection with plants, in view of my own acarological research work, I am particularly interested in the biological development of dying parts of plants through to the return of nutrients into the general biogeochemical cycle. Of course, the activities of various destructive organisms such as bacteria, fungi, nematodes, mites and insects are particularly important. Their presence obviously depends on various aspects.

Conditions, in which I found mites of the Histiostomatidae

The organisms must first be able to get to the fallen fruit, in this case the fallen lemon. They must also have suitable living conditions there. During collecting excursions from 2006 onwards in the area of Sorrento (Italy), which is known for its lemon groves, I examined rotting lemons for Histiostomatidae mites and developed breeding approaches. The mites seemingly only appear, when the lemon is in an already continuing state of decomposition. There are also requirements for sun intensity (shaded), soil quality (rather sandy and  slightly moist) and condition of the fallen fruit (partly moist, sometimes already earthy looking).

A mite of the Histiostomatidae that actively influences the microclimate of its microhabitat and that I used as model to study details of the feeding mechanism

I discovered the mite Histiostoma sp. in 2006. (H. feroniarum-complex, Histiostomatidae, Astigmata). The species arrives at the decomposing lemon fruit phoretically, i.e. it is transported there by a more mobile arthropod. The transporter is still unknown, but dipolopods might be possible transporters. The mite apparently has no problems on the lemon as there is little acid and oil left in the peel residue. Where mites of the Histiostomatidae occur, they take on a creative function for their microhabitat. This is because they can hyperphoretically introduce fungal spores into a habitat and have a chemical effect (L. Koller, S. F. Wirth, G. Raspotnig, 2012) on the growth of fungi that they have brought with them and those that are already present. Among other things, fungicides are formed in certain paired gland systems on the mite’s backsides. The mite was easy to breed under room conditions with the addition of potato pieces to enrich the growth of the food base (dying fungus with bacterial growth). At times I used the mite as a model organism, for example to analyze details of the food intake principle (S. F. Wirth, 2023).

.

© StefanFWirth Berlin 2024

.

.

Photos: details of my blooming and fruit bearing lemon tree (bought, plant trade), scanning electronmicroscopy (SEM) of Histiostoma sp. (H. feroniarum-complex) from rotting lemon fruits in Italy. © Stefan F. Wirth, 2006-2024.

.

.

.

Sources:

T. Faddetta et al. (2021):
https://doi.org/10.1038/s41598-021-86399-5

R. Hartati et al. (2021):
https://ijrps.com/home/article/view/270

L. Koller, S. F. Wirth, G. Raspotnig (2012):
http://dx.doi.org/10.1080/01647954.2012.662247

S. F. Wirth (2023) in FAO, page 102:
https://doi.org/10.4060/cc6728en
corresponding poster publication (2022):
https://wp.me/p2l6XU-1IJ

A bleeding Mary miracle in Germany was in reality due to mites

Mites instead of miraculous blood in the German village Ostro (East Saxony)

Mites instead of a religious miracle. In the East Saxon village of Ostro (Oberlausitz, Germany), an apparently bleeding statue of the Virgin Mary in a field chapel caused a stir. But instead the cause of reddish color effects were aggregating mites that had not yet been fully identified by Technical University-Dresden.

What reddish mites can aggregate in greater number and create the impression of blood?

Gamasina mites such as for example bird mites of the genus Dermanyssus (Parasitiformes) or e.g. from the taxon Erythraeoidea or the taxon Trombidiidae (Trombidiformes, Acariformes) can lead to reddish appearing mite accumulations. From the photos published in the press media in a low magnification of dried mite individuals I can’t see systematically important features such as the body divisions, details of the pedipalps or the clear number of leg articles. But it looks as if the coxae may not be fused with the venter, which would rather point to Parasitiformes than to Acariformes. Gamasina are also bigger than the majority of Trombidiformes, which might be why the reddish aggregation was so impressively visible for the chapel visitors. But I can here only speculate. The TU Dresden according to news media suspects that the animals gathered on the statue to benefit from the warmth at higher altitudes. I would prefer stating that the behaviors in species or taxa depend on the corresponding life-styles, thus climbing up elevations can have different reasons, but there are indeed also thermophilic mites existing in many taxa.

What the diocese announced and why I think that such events should not motivate people to hope for the next miracle to which they could pray, but to get interest in scientific contexts instead, because young scientists are needed

The Dresden-Meißen diocese responded in my opinion sensibly or even „correctly“ by saying it was just one of the many miracles in God’s work of creation, although I would like to add that if there was indeed a creation, then it was the creation of all the countless natural-scientific laws. Describing natural phenomena in general as a kind of miraculous in the sense of „interesting“, „fascinating“ and even „motivating for a closer look to understand more“ could create new naturalists in religious communities who partly may hopefully even participate in future citizen research projects, on biodiversity for example. According to Spiegel magazine (link below, in German), Vicar General Andreas Kutschke also said: “I would like to express my thanks to all the believers who felt called to special prayers by this event. It is optimistic if believers remain sensitive to God’s signs to us humans in this time in many ways.“ Well, what can I say about that? We need more young academics or other professionals in the fields of biology and natural sciences in general. Praying alone is not enough. And the “sensitivity” could bear fruit much more productively on a more solid educational foundation, which generally is in Germany partly not on the level any more, where it was twenty years ago.

.

© Stefan F. Wirth, Berlin 2024

.

.

Photos:
1) village Ostro, author Gunther Alfred Tschuch, 2018, licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
2) Dermanyssus gallinae as example for a reddish mite of the Gamasina (Parasitiformes), author Luis Fernández García, 2007, licensed under the Creative Commons Attribution-Share Alike 2.5 Spain license.
3) A species of Genus Balaustium as example for a reddish mite of the Trombidiformes (Acariformes), author Ted Kropiewnicki, 2009, licensed under the Creative Commons Attribution 2.0 Germany license.

.

.

Source:

Spiegel article in German:

https://www.spiegel.de/panorama/madonna-von-ostro-in-sachsen-angebliche-blutstropfen-waren-milben-kein-wunder-a-9b874f84-35ae-4607-b987-fcfb9b6e3a9f

Diphenism in migratory locusts and about different sensitive stimuli in the context of formation and food efficiency of the gregarious form

About diphenism in migratory locusts and about new research findings on the function of olfactory perception in response to conspecifics in a swarm and in response to food plants.

Schistocerca gregaria as Modell organism and about the polyphyly of migratory locusts

Schistocerca gregaria (Acrididae, Caelifera) is one of the best-known migratory locusts because it is easy to breed for research purposes and because it also plays an important role as a food animal in terraristics, for example. Individials from the commercial animal feed trade are depicted in my attached photos.

Migratory locusts are characterized by two distinctive morphological morphs, which are also associated with different behaviors. However, migratory locusts are not a monophyletic grouping, but rather represent numerous convergent evolutionary lines within the Acrididae, But the dimorphism of migratory locusts always corresponds to more or less a similar principle, which could possibly be at least due to a certain tendency towards a distinct reaction to avoid food competition in a far away last common ancestor species.

Solitary and gregarious forms, food competition and how the development of the gregarious Form is triggered

The diphenism consists in the fact that a solitary living form can be distinctively distinguished from a gregarious living form, i.e. without intermediate forms. The gregarious form is the one that gathers in swarms and then moves away from the original area in usually jerky migration spurts in order to find less densely populated areas with less intraspecific competition for food. Due to the size of these swarms, the migratory locusts can cause significant economic damage to human agriculture through their feeding behavior. The transition from the solitary to the gregarious form takes place within the nymphal stages and remains up to the adults, which due to their possession of wings can migrate over huge distances. Apart from the different behavior, dipenism is also noticeable in the morphology of the nymphs, in which the gregarious morph differs from the solitary morph by a more intense color and additional black patterns. The change from one phase to the other is caused by a too high density of individuals in the solitary form, which is accompanied by increased intraspecific competition for food. More precisely, this dimorphism in migratory locusts is an evolutionary adaptation to avoid competition for food. An immediate trigger that initiates the transition to the gregarious form in S. gregaria is a tactile stimulus that occurs when the legs of individuals crowded together again and again touch each other.

About the difference between dimorphism and diphenism

This stimulus releases the hormone serotonin, which is an important means to induce the gregarious form. However, other aspects also play a role here. What all of these aspects have in common is that, as external environmental influences, they initiate the emergence of one of two morphs. The underlying genetic information alone is not sufficient to allow the two morphs to develop. When only genetic components are responsible for the formation of two distinctly different morphs in the kingdom of living organisms, this is called dimorphism. However, if – as with migratory locusts – the interaction of both together, genetic components and external environmental influences, is necessary to initiate the phenomenon, this is referred to as diphenism.

Role of olfactory behaviors in a swarm

To understand interactions in the gregarious form, a neurological approach is instructive. Different approaches are theoretically conceivable here. One approach, for example, is so-called calcium imaging, in which the movements of intracellular calcium are observed using fluorescence microscopy in order to be able to assess the activity of neurons based on the calcium signals. The authors I. Petelski et al. have shown that it is precisely this method that can provide information about the sensory interactions between individuals in a migratory locust swarm, shown in their preprint (2023). For their studies they used the model organism  S. gregaria that I mentioned earlier. Using this species, the researchers were able to discover that the olfactory perception of the smells of conspecifics in conjunction with the smells of food sources in the swarm play an important role, which can be observed in the antennal lobe. This is interpreted as an adaptation to finding food efficiently in a swarm.

.

© Stefan F. Wirth, Berlin 2024

.

.

Photos:1+2 side and ventral view to an adult of Schistocerca gregaria, 3+4 freshly molted adult, © Stefan F. Wirth, 2020-2024, Berlin

.

.

Sources:

I. Petelski et al. preprint (2023):
https://doi.org/10.1101/2023.09.15.557953

Saharan dust seen from Mauerpark Berlin and about its origin and effects

Saharan air layer (SAL) over Germany end of March 2024

Saharan dust (Saharan air layer (SAL)) over Germany during the Easter holidays and its significance for the weather and ecology. Photos taken on Easter Sunday 2024 in Berlin’s popular Mauerpark park. About the background to the expensive renovation work there.

Thermal turbulences carry Saharan dust up to heights of 5 km

Saharan dust is created due to the extreme ground temperatures of the world’s largest dry desert, which stretches along Africa’s Atlantic coast. Thermal turbulences drive the dust to high altitudes of up to 5000 m, where the particles, which have been ground down to fine sizes between 1 and 74 µm by soil weathering, can remain for months. They reach South America through the trade wind drift. Due to strong south-southwest currents that precede Mediterranean lows, Saharan dust also reaches Europe, which usually happens in spring or autumn and up to fifteen times a year. The Sahara dust air masses that reached Germany around the Easter holidays 2024 were described in various media as being stronger than usual, which is why the phenomenon could be seen for days, particularly clearly in West Germany, but also in Berlin. The greatest intensity across Germany was reached on Easter Saturday. On Easter Sunday the phenomenon could still be seen in the form of a milky, cloudy sky and a corresponding veil over the sun.

Nutrient supply for forests and a possible context to temperatures, important for climate warming research

Saharan dust has various effects on weather and ecosystems worldwide, which are by no means predominantly negative. Sahara dust is actually very rich in nutrients. It is a fallacy to believe that desert sand is hostile to life. The hostility to life in a desert like the Sahara lies in its dryness and heat. The sand, on the other hand, was created from the remains of the bottom of a huge freshwater lake that was there until after the Würm Ice Age (around 10,000 years ago). The sand therefore contains valuable nutrients, such as magnesium and calcium. Due to its global distribution, desert dust may make a significant contribution to the nutrient supply of forests, especially the Amazon rainforests or the forest areas on the Iberian Peninsula. On the other hand, the aerosols containing the dust are suspected of promoting the formation of hurricanes over the Mid-Atlantic, for which they could act as condensation nuclei. In connection with global warming, scientific considerations are also being given to the extent to which the temperature e.g. in South America or Europe could be influenced by the dusty air.

How can the effect of Saharan dust on climate be studied? And what amount of masses is deposited in which pattern?

The authors J.F. Kok et al. (2018) have dealt with the influence of the global Dust cycle and the climate system in the form of a theoretical framework, and although it is unclear what exactly this influence is, the authors consider it likely that the future climate in different areas of the Earth such as North Africa, the Sahel or Central Asia could be influenced by the dust cycle. However, many variables related to the impact of Saharan dust are still unknown. Therefore, the authors M. Dumont et al. (2023) investigated the question of the spatial deposition pattern of Saharan dust in the form of a citizen science campaign, for which they were provided with samples from 70 different locations, mostly in high mountains. The authors noted, among other things, „a decrease in deposited mass and particle sizes with removal of the source along the transport route.“

About Mauerpark Berlin, the site, from which my photos were taken and about the recent construction of an ecological redesign concept

The attached photos were taken by me in the famous Berlin park „Mauerpark“ in the Prenzlauer Berg district, a green space along a former GDR border strip that is very heavily visited on summer days. Now a huge construction site represents an ambitious and expensive redesign concept as part of urban greening and species protection that is scheduled to be completed by 2027.

.

.

Photos: Saharan dust over Park Mauerpark in Berlin, 31 March 2024, ©Stefan F. Wirth

.

.

© Stefan F. Wirth Berlin March 31, 2024

Sources

J.F. Kok et al. (2018)
https://doi.org/10.1038/s41467-017-02620-y

M. Dumont et al. (2023)
https://doi.org/10.5194/essd-15-3075-2023

Article in „Morgenpost“ about the new Mauerpark by T. Schubert (2022)
https://www.morgenpost.de/bezirke/pankow/article237046279/Alles-neu-bis-2027-So-laeuft-das-grosse-Mauerpark-Facelift.html

Yawning in humans and about so called mirror neurons and their functions in primates

Why do we yawn in response to other people’s yawns? And about mirror neurons in primates

When we see a person yawn, it triggers a mirror reaction, a well known human behavioral effect. This can also happen, when visually perceived stimuli look similar to the human yawning behavior we are familiar with, as in the #bird video  by John Delhotal (link below), in which a yawn-like effect was created by a slow motion sequence of a great blue heron (linked below). In any case, I immediately yawned while watching the video. But the video description may also have a suggestive effect. However, my reaction might indicate that I am a very empathetic person. The effect of imitating seen behavioral characteristics in birds and primates (including us humans) is neurobiologically caused by so-called „mirror neurons“ , which show measurable activity when certain behaviors of (normally) a conspecific individual are observed. In human brains these neurons are among others located in the premotor cortex and the primary somatosensory cortex.

Mirror neurons and hypotheses about the functions of those neuron groups based on monkey studies: learning and emotions, such as empathy

The authors H. Théoret & A. Pascual-Leone (2002) deal with mirror neuron populations in monkeys and conclude that the activation of these neuron areas through recurring behaviors of conspecifics contributes to improving their own behaviors by being able to understand the behaviors of others. As an example the authors specifically refer to the learning of language. However, the reaction of the mirror neuron areas is also associated with the development of emotions. An important such emotion is empathy. An editorial article by S. Blakeslee in the New York Times (2006), for example, discusses this.
Important further tags: #evolution #neurobiology #behavioralbiology

© Stefan F. Wirth, Berlin 2024

.

.

Photos 1+2: yawning © Stefan F. Wirth, Berlin 2024

.

.

Sources:

Video by John Delhotal (2024):
https://twitter.com/ImagesByJohnDel/status/1768958565698371941?t=WifgTXPKDnc4zkEYZv6bYw&s=19

H. Théoret & A. Pascual-Leone (2002):
https://doi.org/10.1016/S0960-9822(02)01251-4

S. Blakeslee in the New York Times (2006),
https://www.nytimes.com/2006/01/10/science/cells-that-read-minds.html

About more than two sex types in living organisms and about a ciliate with seven different sexes

Major topics

About more than two sex types in animals and other organisms and a species of unicellular ciliates (Ciliophora, Alveolata), which has seven different sexes, and about how these forms are recognized by each other.

Important characters of the monophyletic Ciliophora

Ciliates are characterized by special features of their morphology and biology (apomorphies). These include the eponymous cilia, which cover the entire cell surface and are used for swimming locomotion, but also take on multiple sensory tasks.
The reproductive mode of ciliates is called conjugation. Individuals come close together and form plasma strands through which genetic material is exchanged. As with all cells in general, components of the cell membrane play a major role in such cell to cell interaction. This is also the case with the well-studied model organism Tetrahymena thermophila (Tetrahymenidae), which must be able to recognize seven different sexes.

About the predominant binary mode of sexual reproduction in animals and a mite with two distinct male forms

Species that can be said to have more than two sexes are rare in animals with multicellular tissue. Across the boundaries of different taxa, the binary mode of sexual reproduction is predominant, in which individuals produce one of two gamete types, eggs or sperm. In most cases in which other forms exist in addition to males and females, one speaks of different mating types rather than different sexes, since, for example, in cases of self-fertilization (hermaphroditism) also only sperm and eggs are involved. On the other hand, species that practice parthenogenesis cannot be assigned to sex because fertilization does not occur and self cloning is carried out instead. Even more than two gender phenotypes are not necessarily an indication of more than two sexes. In the mite species Histiostoma palustre, which I described in 2003 for example, there are two morphologically distinct male forms. However, there is currently no knowledge, whether these also produce different types of sperm.

May be more than two sexes in an edible frog, more sex forms in plants and fungi and about mating-type proteins in T. thermophila

More than two sexual forms in vertebrates might, for example, be spoken of in connection with all-hybrid populations of diploid and triploid edible frogs (Pelophylax esculentus), in which diploid and triploid hybrids contribute „different gamete contributions for successful reproduction“ (see link below). Other examples exist in fungi and plants. While in the multicellular animal kingdom there are obviously biological and ecological constraints that particularly favor the retention of only two gamete types, in the case of the ciliate Tetrahymena thermophila, more options are available, which can be named as different sexes, although the authors of the paper below still use the more neutral term „mating types“ . There are seven forms of sexes that differ from each other  in regard of their mating-type proteins, being localized to their cell surfaces. According to authors Guanxiong Yan et al. (2024), specimens are able to distinguish between the multitude of sexual forms.

Mating type genes and about a dual recognition system via cell surface proteins in  T. thermophila

The different sex types are encoded by the mating type genes MTA1-MTB1 to MTA7-MTB7. The protein complexes MTA and MTB on the cell surfaces act as a dual recognition system, responsible for the specific recognition of a sex type. They also serve at the same time for self-recognition. This is because a cell can „mate“ with any mating type, but not with the type that it represents itself. Such research approaches  generally contribute to the understanding of communication between cells.

.

© Stefan F. Wirth, Berlin 2024

.

1) Ciliate T. thermophila, 2006, author R. Robinson, licensed under the Creative Commons Attribution 2.5 Generic license.
2) Two Tetrahymena cells of complementary mating types, author Jmf368w, 2016, licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

.

.

Sources:

Guanxiong Yan et al. (2024):
https://doi.org/10.7554/eLife.93770.2

Further reading:

S. F. Wirth about H. palustre with different male types (2003):
https://www1.montpellier.inrae.fr/CBGP/acarologia/article.php?id=1849

Gamete types in edible frogs by D. G. Christiansen (2009):
https://doi.org/10.1186/1471-2148-9-135

The 96th AcademyAwards, about some winners and some that didn’t win and about Films as part of the modern human heritage

Celebrating inspiring movies

The 96th AcademyAwards are over, which I really enjoyed watching. Such an event in Hollywood is a big spectacle, it’s about what which star is wearing on the red carpet, it’s about music performances, a little about current political issues and of course about the award ceremony itself. However it makes immense sense to get as many as possible nominated films to have watched in advance. Numerous artistically sophisticated and inspiring films were nominated. But one should not forget that many good and artistically valuable smaller lower budget films are never even considered for award nominations. I say: go also to the smaller art house cinemas, because you otherwise would miss great artworks.

Me as a cinephile

I would definitely describe myself as a cinephile, who even already had chances to look behind some movie settings. for example as extra, stand-in or body double for several smaller and also some larger films,  shot in Berlin or Potsdam, a few years ago.
Such experiences help me today to see more interesting detail when watching films.

About breathtaking show acts and not so breathtaking movies

Some of the feature films I saw leading up to these Oscars were breathtaking, although Barbie (one Oscar for best song) didn’t really take my breath away. But if you consider that in Barbie-Land Ken can do nothing other than „beach“, while Barbie herself can everything from astronaut to Nobel Prize winner, Ken is excellent at getting an Oscar nomination and Barbie herself unfortunately is not. And Ken aka Ryan Gosling can do even more, as his musical performance in the show, where he danced and sang brilliantly, was actually breathtaking.

About the winners and some non-winners, which still deserve to be watched

The science fiction film Poor Things is one of the leading award winners (4 Oscars) at these Oscars, and as was previously suspected, even more the film about American theoretical physicist Robert Oppenheimer (born April 22, 1904 in New York City; † February 18, 1967 in Princeton, New Jersey), who is often called „father of the atomic bomb“

Killers of the Flower Moon was one of my favorites, a dark film set in the 1920s and dealing with the murders of indigenous women who had wealth due to natural resources and were therefore married and murdered by white men (Osage Indian murders), but it won no Oscar. The film Society of the Snow did also not receive an award, but it is still very well worth seeing and was nominated for the best international film category. It shows the fate of a group of athletes who survive a plane crash in the Andes in 1972 and experience the limits of what humans can survive in the midst of unforgiving nature. French movie Anatomy of a Fall with German leading actress Sandra Hüller got  the best Original Screenplay Oscar.

Leading actress and actor and best picture

Emma Stone got the Oscar for the leading actress (Poor Things), which she certainly deserved. Unfortunately I couldn’t see the film. Annette Bening didn’t win for her impressive role as long-distance swimmer Diana Nyad, who I dmittedly would have loved to win.
Al Pacino presented the Oscar for best picture, Oppenheimer won (7 Oscars in total).
This also includes Cillian Murphy, who received the award as leading actor.

Films as modern human heritage

Films are an important part of our culture,  because they have since they exist become immortal witnesses of our human creativity.

© Stefan F. Wirth, Berlin 2024

.

.

Photographies of the true historical events or people behind some of the movies nominated for Oscars 2024:

Photos:
1) Academy award. Per § 107 (US) it is believed that reproduction for criticism, comment, teaching and scholarship constitutes fair use and does not infringe copyright (Wikipedia)

Photographies of the true historical events or people behind some of the movies nominated for Oscars 2024:

2) Robert Oppenheimer as PhD student, author unknown, 1926/27, in the public domain because its copyright has expired and its author is anonymous
3) Albumen print of a group of Osage pictured 1865, William Henry Blackmore, 1865, public domain where the copyright term is the author’s life plus 70 years or fewer. In the US, because before January 1, 1929
4)  Survivors of the plane crash in the Andes in1972, author Héctor Maffuche, 1974, in the public domain because the copyright of this photograph, registered in Argentina, has expired. at least 25 years have passed after the photograph was created.

About the two sex forms in humans and about transident people as members of modern tolerant societies representing also parts of the human biology and about the misuse of biological terms by right wing or conservative people

The biological definition of sexes

Is the biological definition for the two sex forms, prevalent in the animal kingdom, suitable for describing the transident lifestyle of humans, including an arbitrary classification according to their perceived gender identity, as a biological untruth? My answer is no. The biological definition of sexual gender, which in humans only recognizes those individuals, who produce eggs and those, who produce sperm, serves for the phylogenetic comparison of homologous characteristics across the species boundaries within the animal kingdom. Especially when it comes to questions about the mode of reproduction.

Not unbiological or spiritual

The aspect of perceived gender identity in humans is completely ignored in such comparative approaches, as we cannot determine the perceived gender identity of mites, nematodes, lizards or kangaroos. But a phenomenon that is not covered by a certain biological concept for good reasons is by no means automatically unbiological and therefore automatically spiritual, unless an explicit attempt is made to untruthfully describe the above-mentioned biological concept of sexes as inapplicable or as untruth.

When gender identity feeling and sexual gender differ from each other

We humans are biological organisms, which is why everything we think and feel is also of biological origin. Everything is based on processes that take place at the cellular level and depend on the ability of (human) cells to communicate with one another. The feeling of a gender identity that differs from sexual gender, which is tied to the existence of one of two germ cell forms, does not necessarily have to be an indication of a destructive fad, a brutalization of mores, an enemy of conventional family models or the wanton destruction of scientific-biological knowledge.

Diversity of life plans is no reason for the misuse of biological terms by right wing and conservative people

First of all, as a scientist, I unconditionally recognize that it is a real and biological fact that there are people who feel trapped in the „wrong gender“ . I also support that in a modern and tolerant society these people are enabled and supported to live out the gender identity that they believe is right for themselves. It does not contradict biology if a trans man describes himself as a man and a trans woman as a woman, as long as these people do not intend to spread the claim that they finally can produce the germ cells of the opposite sex. It is a clearly biologically based need to want to live according to one’s perceived gender identity, which is why the formal entry on the birth certificate or identity card is irrelevant. Equality laws and anti-discrimination laws in Germany protect trans people in all the diversity of their different facets of life plans. Anyone who defames trans people, insults them or even degrades them as non-existent is violating German law and is in no way entitled to abuse my professional discipline, namely biology, as a cover.

© Stefan F. Wirth, Berlin, 2024

.

.

Photo: digital drawing „two people with their rights to live according to their identity feelings“, © Stefan F. Wirth Berlin 2024

One of the largest snakes in the world: A new species, the northern green anaconda Eunectes akayima, was described after it was identified as distinctly different from its southern sibling species via mitochondrial DNA.

Authors have identified a new Anaconda species, one of the largest snake species in the world: the northern green anaconda.

About cryptic species complexes in general and focused on Squamata with mitochondrial DNA differing zwo vrry similar anaconda forms as two separate species

It has been known for decades that more other species can be hidden behind already known species. One speaks in such cases from cryptic species groups or complexes. However, for a long time it was rarher problematic to be able to distinguish such very similar species from one another. The species concepts that have become more complex, especially in connection with increasingly differentiated options for molecular genetic studies, now make it possible to better recognize cryptic groups of species and to establish them as distinctly different species. In principle, DNA studies are not even necessary for this, as e.g. the eco-species concept also allows species to be differentiated based on their distinct lifestyles. W. Böhme & Th. Ziegler (1997) were e.g. able to name the monitor lizard species Varanus niloticus and V. ornatus as two distinct species via morphology, ecology and distribution studies. However, in case of the northern green anaconda Eunectes akayima (Boidae, Serpentes), the independent species status could not even be determined with nuclear genomic data. However, this was instead achieved using mitochondrial DNA. But according to the authors of the new anaconda paper (see below) „the lack of nuclear support is more likely to be related to inappropriate markers than to a lack of difference“.

About sibling species and the allopatric speciation

The fact that sister species, which are also referred to as sibling species in the case of species that look extremely similar to each other, are often geographically separated from one another can e.g. be explained as result of allopatric speciation, in which an originally insurmountable obstacle did not disappear too long ago (related to the earth’s history) or still exists. At least the phenomenon, in which a northern species and a southern species are in a sibling species relationship, occurs not infrequently in snakes of South America. Examples are Corallus ruschenbergerii or Epicrates maurus,  in the North with their closest relatives in the south. A spatial barrier that explains this presence of northern and southern species in South America does not exist today. But according to the authors of the Anaconda paper (see below) „these patterns likely speak to paleogeographic events that produced this split at the continental scale.“

Northern and Southern Green anaconda

The northern green anaconda Eunectes akayima lives north of the Amazon and east of the Andes, in Ecuador, Venezuela, Trinidad, Guyana, Suriname and French Guiana. Occurrences in Colombia are also suspected. The species is tied to larger bodies of water and cannot easily be distinguished morphologically or ecologically from its sister species, the southern green anaconda Eunectes murinus. A possible size difference should also be taken with caution, although the southern species is described as being up to 5.21 m long, but the northern species is described as being up to 6.3 m. There is evidence from reports by native tribes that in both species significantly longer individuals could exist (11 to 12 meters are sometimes claimed, but there is no verified evidence for this).

Scientific research paper about the new anaconda species and a spectacular video

Researchers J. A. Rivas et al. (2024) have sampled data of the new anaconda species from the area of rivers Orinoco and Rio Negro in Northern South America.

Especially spectacular is a video footage that was published in the context of the species description, showing wildlife researcher Freek Vonk with a remarkable large specimen (allegedly 26 feet = 7.9 m) of the northern green anaconda under water.

©  Stefan F. Wirth, Berlin 2024

.

.

Photo:
E. akayima at the Hato El Cedral, author Fernando Flores, 2013, licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.

.

.

Sources:

Böhme & Ziegler (1997):
https://www.thebhs.org/publications/the-herpetological-journal/volume-7-number-4-october-1997/1505-04-a-taxonomic-review-of-the-varanus-polydaedalus-niloticus-linnaeus-1766-species-complex

J. A. Rivas et al. (2024): https://doi.org/10.3390/d16020127

Video with F. Vonk swimming with a northern green anaconda:
https://twitter.com/Rainmaker1973/status/1760360560632164820?t=4upmG4Wa6laKmbn6KgzT_Q&s=19

Stridulating young winged queens of the leafcutting ant Atta texana

Masses of leafcutting winged alates after a mating flight attempt

My new Youtube-Video. A situation that one does not encounter very often: hundreds of winged allates of the leafcutting ant Atta texana (Myrmicinae, Formicidae) after their mating flight were made available to me for scientific studies. Packed tightly together in a big box, the noticeably large animals sent out clearly audible cries for help, they stridulated, clearly audible to the human ear. What happened? Early one morning, forestry workers found the animals crowded together near a street lamp, which had apparently attracted the young queens. They had just completed their mating flights, as the leaf-cutting ant Atta texana flies in the #morning darkness.

Non fertilized after an unsuccessful mating flight

The whole thing happened in Louisiana (USA), where I worked with the forest researcher, entomologist and acarologist John C. Moser as part of a research stay in 2009. It was actually about mites from the Histiostomatidae (Astigmata), which are phoretically tied to the red invasive fire ant Solenopsis invicta. However, since I had biologically studied the mite Histiostoma bakeri in Atta texana nests two years previously with the same cooperation partner (S. F. Wirth & J. C. Moser, 2008), I hoped to become able to document the development of this phoretic mite during the nest founding behavior of the young A. texana queens. The young queens survived breeding approaches for a while as long as I added fungus cultivar. However, they were unable to grow their own fungus independently and did not lay any eggs. Specimens that Moser released in the field also did not establish colonies. We therefore assumed that all animals were non-fertilized.

Behavioral context of stridulation in ants with specific focus on Atta texana

But fortunately at least the stridulation behavior of the winged young queens could be clearly observed. Because of their considerable size, I was able to record the stridulation sound using the built-in microphone of a standard compact camera. The stridulation mechanism was also clearly visible to the naked eye. According to F. Barbero et al. (2009) Myrmica queens stridulate to „elicit increased benevolent responses from workers, reinforcing their supreme social status“. According to F. A. Hager, L. Kirchner, W. H. Kirchner (2017) leafcutter ant workers stridulate in the context of „foraging, alarm signaling and collective nest building“. F. Roces, J. Tautz, B. Hölldobler (1993) describe the stridulation mechanism in Atta and explain the stridulation of workers in the context of the common leaf cutting procedure. According to A. Masoni et al. (2021), ant workers of genus Crematogaster modulate stridulating in their different behavioral contexts. I consider the stridulatory signals of the A. texana winged queens in my footage to function as alarm signal. A behavior that only could cause a useful response before their mating flights, when they were still in their maternal nests. It remained unknown, why these alates were not mated.

© Stefan F. Wirth, Berlin 2024 (footage 2009)

.

Photo: left side with crowd of winged Atta texana queens in a box, left side with the stridulation area in dorsal view to the gaster. © Stefan F. Wirth 2009 – 2024

.

.

Sources:

Please watch my full #video in a better resolution on my #Youtube channel and give it a like please:

My YouTube video about stridulating young queens of Atta texana, © Stefan F. Wirth 2009 – 2024

.

.

S. F. Wirth & J. C. Moser (2008):

Wirth, S. & Moser, J.C. (2008): Interactions of histiostomatid mites (Astigmata) and leafcutting ants

.

.

.

F. Barbero et al. (2009):

http://www.jstor.org/stable/20403024

F. A. Hager, L. Kirchner, W. H. Kirchner (2017):

https://doi.org/10.1242/bio.029587

F. Roces, J. Tautz, B. Hölldobler (1993):

file:///C:/Users/wirth/Downloads/1993_Roces-Tautz-Hoelldobler-Naturwiss.pdf

A. Masoni et al. (2021):

https://doi.org/10.1038/s41598-021-84925-z