scholarly journals Distribution of flying insects across landscapes with intensive agriculture in temperate areas

2021 ◽  
Vol 129 ◽  
pp. 107889
Author(s):  
C.J.M. Musters ◽  
Tracy R. Evans ◽  
J.M.R. Wiggers ◽  
Maarten van 't-Zelfde ◽  
Geert R. de Snoo
Keyword(s):  
Intensive Agriculture ◽  
Flying Insects

Organochlorine Residues in Brook Trout and Yellow Perch From New Brunswick and Nova Scotia (Canada) Lakes

1987 ◽  
Vol 22 (3) ◽  
pp. 352-364
Author(s):  
R. Peterson ◽  
S. Ray
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Brook Trout ◽  
Yellow Perch ◽  
Intensive Agriculture ◽  
Fish Tissues ◽  
North Central ◽  
Ddt Metabolites ◽  
Headwater Lakes

Abstract Brook trout and yellow perch collected while surveying New Brunswick and Nova Scotia headwater lakes were analyzed for DDT metabolites, chlordane, hexacyclohexane isomers, hexachlorobenzene, toxaphene and PCB’s. Concentrations of DDT metabolites were much higher from fish taken from lakes in north-central N.B. (200-700 ng/g wet wt) than from fish taken elsewhere (<10 ng/g). Seventy to 90% of the DDT metabolites was DDE. Chlordane (3-13 ng/g) was analyzed in seven trout, six of them from central N.B. areas with intensive agriculture. Isomers of hexachlorocyclohexane were in highest concentration from north-central N.B. (10-20 ng/g), eastern N.S. (5-15 ng/g) and southern N.B. (5-20 ng/g). In most cases, alpha-hexachlorocyclohexane (lindane) was the isomer in highest concentration. Concentrations of hexachlorobenzene in fish tissues was highly variable with no obvious geographic bias. PCB’s were detected in very few fish, and no toxaphene was detected.

scholarly journals Hox dosage contributes to flight appendage morphology in Drosophila

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rachel Paul ◽  
Guillaume Giraud ◽  
Katrin Domsch ◽  
Marilyne Duffraisse ◽  
Frédéric Marmigère ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Differential Expression ◽  
Hox Genes ◽  
Expression Profiles ◽  
Fruit Fly ◽  
Insect Species ◽  
Wing Morphology ◽  
Hox Proteins ◽  
Spatial Expression ◽  
Flying Insects

AbstractFlying insects have invaded all the aerial space on Earth and this astonishing radiation could not have been possible without a remarkable morphological diversification of their flight appendages. Here, we show that characteristic spatial expression profiles and levels of the Hox genes Antennapedia (Antp) and Ultrabithorax (Ubx) underlie the formation of two different flight organs in the fruit fly Drosophila melanogaster. We further demonstrate that flight appendage morphology is dependent on specific Hox doses. Interestingly, we find that wing morphology from evolutionary distant four-winged insect species is also associated with a differential expression of Antp and Ubx. We propose that variation in the spatial expression profile and dosage of Hox proteins is a major determinant of flight appendage diversification in Drosophila and possibly in other insect species during evolution.

scholarly journals Advances in automatic identification of flying insects using optical sensors and machine learning

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Carsten Kirkeby ◽  
Klas Rydhmer ◽  
Samantha M. Cook ◽  
Alfred Strand ◽  
Martin T. Torrance ◽  
...  
Keyword(s):  
Machine Learning ◽  
Optical Sensors ◽  
Precision Agriculture ◽  
Insect Pests ◽  
Crop Damage ◽  
Automatic Identification ◽  
Flying Insects ◽  
Remote Sensor ◽  
Promising Solution ◽  
Environmentally Sensitive

AbstractWorldwide, farmers use insecticides to prevent crop damage caused by insect pests, while they also rely on insect pollinators to enhance crop yield and other insect as natural enemies of pests. In order to target pesticides to pests only, farmers must know exactly where and when pests and beneficial insects are present in the field. A promising solution to this problem could be optical sensors combined with machine learning. We obtained around 10,000 records of flying insects found in oilseed rape (Brassica napus) crops, using an optical remote sensor and evaluated three different classification methods for the obtained signals, reaching over 80% accuracy. We demonstrate that it is possible to classify insects in flight, making it possible to optimize the application of insecticides in space and time. This will enable a technological leap in precision agriculture, where focus on prudent and environmentally-sensitive use of pesticides is a top priority.

scholarly journals Southeast Asian clearwing moths buzz like their model bees

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Marta Skowron Volponi ◽  
Luca Pietro Casacci ◽  
Paolo Volponi ◽  
Francesca Barbero
Keyword(s):  
Slow Motion ◽  
Southeast Asian ◽  
Batesian Mimicry ◽  
Evolutionary Models ◽  
Acoustic Parameters ◽  
Warning Signals ◽  
Visual Model ◽  
Flying Insects

Abstract Background The endless struggle to survive has driven harmless species to evolve elaborate strategies of deceiving predators. Batesian mimicry involves imitations of noxious species’ warning signals by palatable mimics. Clearwing moths (Lepidoptera: Sesiidae), incapable of inflicting painful bites or stings, resemble bees or wasps in their morphology and sometimes imitate their behaviours. An entirely unexplored type of deception in sesiids is acoustic mimicry. We recorded the buzzing sounds of two species of Southeast Asian clearwing moths, Heterosphecia pahangensis and H. hyaloptera and compared them to their visual model bee, Tetragonilla collina, and two control species of bees occurring in the same habitat. Recordings were performed on untethered, flying insects in nature. Results Based on eight acoustic parameters and wingbeat frequencies calculated from slow-motion videos, we found that the buzzes produced by both clearwing moths highly resemble those of T. collina but differ from the two control species of bees. Conclusions Acoustic similarities to bees, alongside morphological and behavioural imitations, indicate that clearwing moths display multimodal mimicry of their evolutionary models.

The toxicity of some insecticidal sprays to adult locusts

1962 ◽  
Vol 53 (3) ◽  
pp. 597-608 ◽  
Author(s):  
R. D. MacCuaig
Keyword(s):  
Schistocerca Gregaria ◽  
Droplet Diameter ◽  
Flight Activity ◽  
Spray Application ◽  
Single Drop ◽  
Flying Insects ◽  
Spray Droplets ◽  
Tentative Explanation

The toxicities of sprays of some insecticides used against locusts have been determined. The LD50's of γ BHC, diazinon, and dieldrin to both flying and settled adults of Schistocerca gregaria (Forsk.) were between 0·9 and 1·5 times those of the same formulations when applied as a single drop to the abdomen. The toxicity of these insecticides was not affected by the size of the spray droplets when these ranged from about 60 to 250 µ in diameter. The toxicity of DNC, however, was always less by spray application than when applied by micro-drop syringe and was affected by the droplet diameter (droplets of 100 µ being 1·5 times as toxic as those of 200–230 µ) and by whether the locusts were sprayed in flight or when tethered on a card (those in flight being about 1·6 times as susceptible to 100 µ droplets as those at rest). A tentative explanation of this effect is given.The speed of action of the insecticides was compared and the effects of flight activity on susceptibility to the insecticides when sprayed over the flying insects was examined, but none could be detected by the technique used.

Population Fluctuation and the Adoption of Food Production in Prehistoric Korea: Using Radiocarbon Dates as a Proxy for Population Change

Radiocarbon ◽  
2017 ◽  
Vol 59 (6) ◽  
pp. 1761-1770 ◽  
Author(s):  
Yongje Oh ◽  
Matthew Conte ◽  
Seungho Kang ◽  
Jangsuk Kim ◽  
Jaehoon Hwang
Keyword(s):  
Probability Distribution ◽  
Population Growth ◽  
Food Production ◽  
Population Change ◽  
Population Pressure ◽  
Population Fluctuation ◽  
Intensive Agriculture ◽  
Rice Farming ◽  
Radiocarbon Dates ◽  
Transition To Agriculture

AbstractPopulation growth has been evoked both as a causal factor and consequence of the transition to agriculture. The use of radiocarbon (14C) dates as proxies for population allows for reevaluations of population as a variable in the transition to agriculture. In Korea, numerous rescue excavations during recent decades have offered a wealth of14C data for this application. A summed probability distribution (SPD) of14C dates is investigated to reconstruct population trends preceding and following adoptions of food production in prehistoric Korea. Important cultivars were introduced to Korea in two episodes: millets during the Chulmun Period (ca. 6000–1500 BCE) and rice during the Mumun Period (ca. 1500–300 BCE). The SPD suggests that while millet production had little impact on Chulmun populations, a prominent surge in population appears to have followed the introduction of rice. The case in prehistoric Korea demonstrates that the adoption of food production does not lead inevitably towards sustained population growth. Furthermore, the data suggest that the transition towards intensive agriculture need not occur under conditions of population pressure resulting from population growth. Rather, intensive rice farming in prehistoric Korea began during a period of population stagnation.

Sign in / Sign up

Export Citation Format

Share Document