Web damage during prey capture in Hyptiotes paradoxus (C.L.KOCH 1834) (Uloboridae)

H. paradoxus - well known for its characteristic triangular web - has frequently been described to always completely collapse its web when catching prey. The aim of the present article is to show that this is not the case, and to discuss how the myth of the obligate complete collapse of the web has arisen and why it survived so well.Es wurde oft beschrieben, dass das charakteristische, dreieckige Netz von H. paradoxus beim Fang einer Beute vollständig zerstört wird. Diese Arbeit zeigt auf, dass dies meist nicht der Fall ist und diskutiert, wie sich der Mythos der obligaten vollständigen Netzzerstörung bildete, und wieso er sich soweit verbreiten konnte

Taking Interstate Rights Seriously

When the U.S. Supreme Court in the 2019 case of Franchise Tax Board v. Hyatt held that the Constitution bars private suits against a state in another state’s courts, it endorsed a surprisingly shallow conception of state sovereign power. But the doctrinal alternative from the now-overruled Nevada v. Hall is no better. Where Hyatt gives too much constitutional protection to would-be defendant states, Hall gives too little. And both approaches mistakenly conceive of interstate sovereign immunity as an on/off switch that the Constitution locks in one position. Finding neither Hyatt III nor Hall satisfactory, I offer a third view. The Full Faith and Credit Clause was meant to ensure that states extend to each other dignity and respect for their sovereign duties. In the case of private suits against a defendant state in another state’s court, these sovereign duties conflict, and it is impossible for a forum state to preserve the sovereign duties of another state without impairing its own. To ensure full faith and credit, the Constitution, I argue, requires that states extend sovereign immunity to their sister states only when doing so maximizes the total sovereign power available to both states. In my view, this approach to interstate sovereign immunity is more consistent with the crucial value precipitated by the Constitution and enshrined in our federal system: states respect each other

Compelled Climate Speech

Climate change threatens nearly every corner of human life and may structurally change the global financial system. Investors increasingly demand information about how climate change may impact their investments. In response, the U.S. Securities and Exchange Commission issued a proposed rule that would require registered companies to disclose certain climate-related information in their registration statements and annual reports. But some critics argue that this proposed rule is unconstitutional under the Supreme Court’s current doctrine on compelled and commercial speech. This doctrine misunderstands the First Amendment. When corporations engage in speech that possesses commercial and non-commercial characteristics, the Court’s binary, categorical conception of the compelled speech doctrine divorces from the constitutional values that the First Amendment protects. This paper identifies those values, analyzes the Court’s current doctrine through the lens of compelled climate speech, and proposes an alternative doctrine that better understands of corporations, the natural persons with whom they interact, and the constitutional rights shaped by those interactions

Die Cestoden der Marsupialia und Monotremata

Ueber Bandwürmer aus Monotremen und Marsupialiern war bis heute nur wenig bekannt, und die wenigen Notizen und Abbildungen entsprechen nur in ungenügendem Maasse den Anforderungen einer wissenschaftlichen Beschreibung und der neueren, auf anatomische Merkmale sich gründenden Cestodensystematik. Im Jahre 1819 beschrieb RUDOLPHI (20) in seiner "Synopsis" unter dem Namen Taenia festiva einen Bandwurm aus den Lebergängen und der Gallenblase von Macropus giganteus, und BREMSER (3) lieferte in den "Icones Helminthum" treffliche Illustrationen dazu. Soweit Beschreibung und Abbildungen Schlüsse gestatten, dürfte der Parasit am ehesten in das von STILES (26) so eingehend beschriebene Genus Monie,da gehören, eine Ansicht, die auch von BLANCHARD (2) vertreten wird. Dafür spricht, ausser der Gestaltung von Scolex und Strobila, besonders die deutliche Trennung der in jeder Proglottide sich in Zweizahl ausbildenden Gruppen von Genitalorganen. Als zweifelhafte Art führt RUDOLPHI Taenia didelphidis aus Didelphys murina an, ohne eine Beschreibung beizufügen. Ueber ein reiches Material von Tänien aus australischen Vögeln und Säugethieren verfügte KREFFT (7). Doch muss ich mich der Ansicht v. LINSTOW'S (9) anschliessen, der bemerkt, dass die Schrift des genannten Autors den heutigen Bedürfnissen der Wissenschaft nicht entspreche. Die Schilderung der gesammelten Helminthen beschränkt sich auf die äussere Körpererscheinung und gestattet keine Schlüsse in Bezug auf die systematische Stellung. KREFFT'S Arbeit beansprucht unser Interesse nur insofern, als sie uns den Beweis liefert, dass Tänien in Marsupialia keine allzu seltene Erscheinung sind. Als sicher verbürgte Funde werden angeführt: Taenia mastersii aus einer Art von Halmaturus und T. phalangistae aus dem Darm von Phalangista vulpina. Einige weitere Angaben über Vorkommen von Cestoden in Beutelthieren werden von KREFFT selbst nur unter allem Vorbehalt gegeben. In neuester Zeit hat D'ARCY W. THOMPSON (27) einen Darmschmarotzer aus Echidna unter dem Namen Taenia echidnae beschrieben. Es standen dem englischen Forscher nur wenige und zudem stark contrahirte Exemplare des Wurms zur Verfügung. Eine anatomische Charakterisirung der neuen Art wird nicht gegeben; immerhin genügen Beschreibung und Abbildungen zur Wiedererkennung der Form. Auf die eben aufgezählten Schriften gründete sich unsere bisherige Kenntniss über die Bandwürmer der Monotremata und Marsupialia. So musste es wünschenswerth erscheinen, das von SEMON in Australien gesammelte und sorgfältig conservirte Cestodenmaterial einer genaueren Untersuchung zu unterziehen. Die Frage nach der Organisation und systematischen Stellung der Parasiten der niedersten Säugethiere durfte wohl ein gewisses Interesse beanspruchen. Es hat sich im Verlaufe der Untersuchung denn auch ergeben, dass nicht nur das Vorkommen der SEMON'schen Cestoden ein eigenthümliches ist, sondern dass dieselben auch in anatomischer und systematischer Beziehung mehrfach Beachtung verdienen. Zur Untersuchung lagen drei Arten von Cestoden in reichlichen Exemplaren vor: Eine Tänie aus dem Darme von Echidna hystrix, die ich aus weiter unten zu erörternden Gründen mit Taenia echidnae n' ARCY W. THOMPSON identificire; und zwei neue Arten: Taenia obesa, aus dem Darme von Phascolarctus cinereus, und Taenia semoni, aus dem Darme von Perameles obesula. In einem ersten Abschnitte der vorliegenden Arbeit sollen die drei Tänien anatomisch geschildert werden; der zweite Theil soll die aus dieser Schilderung sich ergebenden Schlüsse über die gegenseitige Verwandtschaft der drei Formen und über ihre systematische Stellung ziehen, sowie ihre Beziehung zu den Tänien der Placentalia erläutern

Distorted Sex Ratio at Birth in the Captive Pygmy Hippopotamus, Hexaprotodon Liberiensis

The total captive population of the pygmy hippopotamus Hexaprotodon (=Choeropsis) liberiensis has a highly female-biased sex ratio at birth (41% males), which exceeds most of the other known distorted sex ratios in captive mammals. Deviation from an even sex ratio was not compensated by a higher juvenile mortality in females. I examined the possible causes of that deviation and could not find any association between offspring sex and inbreeding, parity, or mother's age. I found, however, a significant difference in sex ratios among different zoological gardens, suggesting that husbandry influenced sex at birth in the pygmy hippopotamus. Further analysis suggested that high feeding intensity and "hands-on” husbandry favored production of daughters. However, not all the observed patterns and relationships could be explained by classic sex ratio theorie

The Problem of Soil Saving in the Hawaiian Islands

This bulletin covers prevention and methods of control of erosion in agricultural lands in Hawaii

Asymmetry in Orb-Webs: An Adaptation to Web Building Costs?

Orb-web spiders build vertically asymmetric webs, in which the lower part is larger than the upper part. One hypothesis explaining this asymmetry suggests that the spider's mass imposes higher building costs in the upper part of the web, causing the spider to reduce this part of the web. We tested this hypothesis by assessing building costs of different parts of the web. We found that the specific time-cost of building (i.e. the time required to build a certain length of silk) differed between the two parts of the web and that the difference in time-costs influenced web asymmetry. Contrary to predictions, however, building costs were larger in the lower part of the web, suggesting that additional factors affect the spider's decisions while building the web, which are likely to be prey-capture consideration

First records and data about the biology of Cyclosa oculata (Araneae: Araneidae) in Switzerland

Die Radnetzspinne Cyclosa oculata (Walckenaer, 1802) wurde an elf Orten in der Nordwestschweiz nachgewiesen. Alle Fundorte lagen in Buntbrachen mit relativ hohem Anteil abgestorbener Vegetation vom Vorjahr, relativ niedriger Vegetationshöhe und geringem Anteil von Gräsern an der Vegetation. C. oculata baute ihr kleines Radnetz in Bodennähe, tief in der Vegetation. Unter den ecribellaten Radnetzspinnen Mitteleuropas ist C. oculata einzigartig, da sie manchmal ein rudimentäres Netze baut und verwendet, da sie ihre Kokons in das Netz einbaut, und da sie ein dauerhaftes Detritus-Stabiliment baut. Aufgrund unserer Beobachtungen nehmen wir an, dass das Stabiliment C. oculata zur Tarnung dient.The orb-web spider Cyclosa oculata (Walckenaer, 1802) was found at eleven localities in north-western Switzerland. All records were from wildflower strips ("Buntbrachen") with a relatively high proportion of dried vegetation from the previous year, a relatively low vegetation height and a low proportion of grasses in the vegetation. C. oculata built its vertical orb-web near the ground, deep in the vegetation. Among ecribellate orb-web spiders in Central Europe, C. oculata is unique because it sometimes builds rudimentary webs on which it stays, because it builds its cocoons into the web, and because its stabilimentum is long-lasting and consists largely of debris. Based on our observations, we deduce that the stabilimentum of C. oculata serves as camouflage

Spider orientation and hub position in orb webs

Orb-web building spiders (Araneae: Araneoidea, Uloboridae) can be considered as territorial central place foragers. In territorial central place foragers, the optimal foraging arena is circular, with the forager sitting in its centre. In orb webs, the spider's orientation (head up or head down) whilst waiting for prey on the hub of its web and the downwards-upwards asymmetry of its running speeds are the probable causes for the observed deviation of the hub from the web's centre. Here, we present an analytical model and a more refined simulation model to analyse the relationships amongst the spider's running speeds, its orientation whilst waiting for prey and the vertical asymmetry of orb webs. The results of our models suggest that (a) waiting for prey head down is generally favourable because it allows the spider to reach the prey in its web on average quicker than spiders waiting head up, (b) the downwards-upwards running speed asymmetry, together with the head-down orientation of most spiders, are likely causes for the observed vertical asymmetry of orb webs, (c) waiting head up can be advantageous for spiders whose downwards-upwards running speed asymmetry is small and who experience high prey tumbling rates and (d) spiders waiting head up should place their hub lower than similar spiders waiting head dow

Untangling the Tangle-Web: Web Construction Behavior of the Comb-Footed Spider Steatoda triangulosa and Comments on Phylogenetic Implications (Araneae: Theridiidae)

Theridiidae typically construct a three-dimensional web often described as "irregular.” The web consists of a supporting structure and lines under tension termed gumfooted lines. We used automated methods to observe web construction in the theridiid Steatoda triangulosa under laboratory conditions. Web construction lasted several nights. After orientation, spiders built a three-dimensional structure of several threads radiating sideways and downward from the retreat. To build gumfooted lines, they started from the retreat, moved along a structural thread, then dropped down to attach the thread to the lower substrate. On returning, they coated the lowest part of the thread with viscid silk before moving up along the same thread back to the structural thread. They then continued moving along the same structural thread to drop down again to build the next gumfooted line. This behavior was continued until the spiders had built a series of gumfooted lines (a bout). There were regular intervals between the construction of two bouts. Thus, a single web included many bouts built in different stages. We show that gumfooted lines are not homologues to sticky web elements of orb-weavers and present new synapomorphic characters that support the monophyly of Theridiidae + Nesticidae and the monophyly of araneoid sheet web weavers. Further, the time allocation pattern for different behavioral stages and the fine structure of a gumfooted line are presente