Ego in amorem inciderem ... et ego tristis spectator - Die Autobiographie des jülich-bergischen Rates Petrus Simonius Ritz (1562-1622)

Der vorliegende Beitrag stellt die 1604 verfasste und bislang unveröffentlichte Autobiographie des kurtrierischen, jülich-bergischen und nach dem Zerfall der Vereinigten Herzogtümer Jülich-Kleve-Berg pfalz-neuburgischen Rates Petrus Simonius Ritz (1562-1622) vor. Seit 1595 stand der Schreiber in jülich-bergischen Diensten und nahm bis zu seinem Tod an fast allen bedeutsamen Ereignissen der damals angespannten politischen Situation am Niederrhein teil. Bei Beachtung der Klischees, die Simonius in seiner Selbstdarstellung verwendet, dürfte die mitunter sehr detaillierte und aufmerksame Beschreibung seiner alltäglichen Wahrnehmungen den besonderen Wert der Aufzeichnungen ausmachen. Er erzählt von seinem Bildungsweg, von Heirat, Krankheit und dem Tode seiner ersten Frau, der anschließenden Wiederverheiratung und natürlich auch vom Alltag bei Hofe.

The impact of plant diversity and fertilization on fitness of a generalist grasshopper

In many environments land use intensification is likely to result in a decrease in species richness and in an increase in eutrophication. Although the importance of both factors for higher trophic levels such as insect herbivores is well documented, their impact has rarely been studied in combination. Herbivorous insects have a strong impact on the functioning of ecosystems and it is therefore important to understand how they are affected by eutrophication in high or low diversity environments. We used a grassland biodiversity experiment to investigate the combined effect of fertilization and plant diversity loss on the fitness of the generalist grasshopper Chorthippus parallelus by rearing grasshopper nymphs for four weeks in cages on unfertilized or fertilized (NPK) subplots across a species richness gradient from 1 to 60 plant species. Survival, the number of oothecae, body mass and the number of hatchlings were measured separately for each cage. Plant diversity had no effect on any of the grasshopper fitness measures, neither in unfertilized nor in fertilized plots. NPK-fertilization reduced grasshopper survival but increased body mass of males and reproductive success of the surviving females. Fertilization effects were not mediated by plant community structure, productivity or composition, suggesting that higher food plant quality was one of the main drivers. There was no interaction between plant diversity and fertilization on any of the measures. In conclusion, an increase in eutrophication, in both species-rich and species-poor grasslands, could lead to higher reproductive success and therefore higher abundances of herbivorous insects including insect pests, with fertilization effects dominating plant diversity effects.

Organization of the Hox gene cluster in the grasshopper, Schistocerca gregaria

The conserved organization of the Hox genes throughout the animal kingdom has become one of the major paradigms of evolutionary developmental biology. We have examined the organization of the Hox genes of the grasshopper, Schistocerca gregaria. We find that the grasshopper Hox cluster is over 700 kb long, and is not split into equivalents of the Antennapedia complex and the bithorax complex of Drosophila melanogaster. SgDax and probably also Sgzen, the grasshopper homologues of fushi-tarazu (ftz) and Zerknüllt (zen), respectively, are also in the cluster, showing that the non-homeotic Antp-class genes, “accessory genes,” are an ancient feature of insect Hox clusters.

Grasshopper crop and midgut extract effects on plants: an example of reward feedback.

Acid extracts and a resultant fraction from solid-phase extraction (SPE) of Romalea guttata crop and midgut tissues induce sorghum (Sorghum bicolor var. Rio) coleoptile growth in 24-h incubations an average of 49% above untreated controls. When combined with plant auxin, indole-3-acetic acid (IAA), the SPE fraction shows a synergistic reaction, yielding increases in coleoptile growth that average 295% above untreated controls and 8% above IAA standards. The interaction lowered the point of maximum sensitivity of IAA 3 orders of magnitude, resulting in a new IAA physiological set point at 10(-7) g/ml. This synergism suggests that contents in animal regurgitants making their way into plant tissue during feeding may produce a positive feedback in plant growth and development following herbivory. Such a process, also known as reward feedback, may exert major controls on ecosystem-level relationships in nature.

Birds in relation to a grasshopper outbreak in California,

Mode of access: Internet.

Knee-high to a grasshopper,

Mode of access: Internet.

The life of the grasshopper,

Some of the chapters have already appeared, part under different titles and part in an abbreviated form, in an interesting miscellany extracted from the Souvenirs, translated by Mr. Bernard Miall, under the title of Social life in the insect world. cf. Translator's note.

The abdominal mechanisms of a grasshopper,

Publication 3335.

Grasshopper green and the meadow-mice /

Mode of access: Internet.

Grasshopper integrated pest management handbook.

Title on disk: Hopper.

Observations on mass flights and other activities of the migratory grasshopper /

Includes bibliographical references (p. 46).

Grasshopper egg pods destroyed by larvae of bee flies, blister beetles, and ground beetles /

Literature cited: p. 28-29.

The High Plains grasshopper : a compilation of facts about its occurrence and control /

Includes bibliographical references (p. 156-168).