The Insects has been the standard textbook in the field since the first edition published over forty years ago. Building on the strengths of Chapman's original text, this long-awaited 5th edition has been revised and expanded by a team of eminent insect physiologists, bringing it fully up-to-date for the molecular era. The chapters retain the successful structure of the earlier editions, focusing on particular functional systems rather than taxonomic groups and making it easy for students to delve into topics without extensive knowledge of taxonomy. The focus is on form and function, bringing together basic anatomy and physiology and examining how these relate to behaviour. This, combined with nearly 600 clear illustrations, provides a comprehensive understanding of how insects work. Now also featuring a richly illustrated prologue by George McGavin, this is an essential text for students, researchers and applied entomologists alike.

The insects: structure and function.

Mosaic analysis with a repressible cell marker for studies of gene function in neuronal morphogenesis.

The administration of leptin to leptin-deficient humans, and the analogous Lepob/Lepob mice, effectively reduces hyperphagia and obesity. But common obesity is associated with elevated leptin, which suggests that obese humans are resistant to this adipocyte hormone. In addition to regulating long-term energy balance, leptin also rapidly affects neuronal activity. Proopiomelanocortin (POMC) and neuropeptide-Y types of neurons in the arcuate nucleus of the hypothalamus are both principal sites of leptin receptor expression and the source of potent neuropeptide modulators, melanocortins and neuropeptide Y, which exert opposing effects on feeding and metabolism. These neurons are therefore ideal for characterizing leptin action and the mechanism of leptin resistance; however, their diffuse distribution makes them difficult to study. Here we report electrophysiological recordings on POMC neurons, which we identified by targeted expression of green fluorescent protein in transgenic mice. Leptin increases the frequency of action potentials in the anorexigenic POMC neurons by two mechanisms: depolarization through a nonspecific cation channel; and reduced inhibition by local orexigenic neuropeptide-Y/GABA (gamma-aminobutyric acid) neurons. Furthermore, we show that melanocortin peptides have an autoinhibitory effect on this circuit. On the basis of our results, we propose an integrated model of leptin action and neuronal architecture in the arcuate nucleus of the hypothalamus.

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Leptin activates anorexigenic POMC neurons through a neural network in the arcuate nucleus

Recent advances in integrative studies of locomotion have revealed several general principles. Energy storage and exchange mechanisms discovered in walking and running bipeds apply to multilegged locomotion and even to flying and swimming. Nonpropulsive lateral forces can be sizable, but they may benefit stability, maneuverability, or other criteria that become apparent in natural environments. Locomotor control systems combine rapid mechanical preflexes with multimodal sensory feedback and feedforward commands. Muscles have a surprising variety of functions in locomotion, serving as motors, brakes, springs, and struts. Integrative approaches reveal not only how each component within a locomotor system operates but how they function as a collective whole.

https://science.sciencemag.org/content/sci/288/5463/100.full.pdf

How Animals Move: An Integrative View

We have developed a method for temporal and regional gene expression targeting (TARGET) in Drosophila and show the simultaneous spatial and temporal rescue of a memory defect. The transient expression of the rutabaga-encoded adenylyl cyclase in the mushroom bodies of the adult brain was necessary and sufficient to rescue the rutabaga memory deficit, which rules out a developmental brain defect in the etiology of this deficit and demonstrates an acute role for rutabaga in memory formation in these neurons. The TARGET system offers general utility in simultaneously addressing issues of when and where gene products are required.

https://science.sciencemag.org/content/sci/302/5651/1765.full.pdf

Spatiotemporal rescue of memory dysfunction in Drosophila

Common design in a unique midline neuropil in the brains of arthropods.

Neck muscles of Calliphora erythrocephala, situated in the anterior prothorax, are innervated on each side by 8 motor neurons arising in the brain (cervical nerve neurons, CN1–8) and at least 13 motor neurons arising in the prothoracic ganglion (anterior dorsal and frontal nerve neurons, ADN1,2 and FN1-11). Three prominent motor neurons (CN6 and FN1,2) are described in detail with special emphasis on their relationships with giant visual interneurons from the lobula plate, haltere interneurons, and primary afferents from the prosternal organs and halteres. These sensory organs detect head movement and body yaw, respectively. Neuronal relationships indicate that head movement is under multimodal sensory control that includes giant motion-sensitive neurons previously supposed to mediate the optomotor response in flying flies. The described pathways provide anatomical substrates for the control of optokinetic and yaw-incurred head movements that behavioural studies have shown must exist.

Convergence of visual, haltere, and prosternai inputs at neck motor neurons of Calliphora erythrocephala

http://link.springer.com/content/pdf/10.1007/978-3-642-66907-1_1.pdf

Neuroarchitectures Serving Compound Eyes of Crustacea and Insects

The evolution of crustacean and insect optic lobes and the origins of chiasmata

Like horizontal cells in vertebrate retinas, horizontal amacrine cells beneath the insect eye intervene between receptors and interneurons at the first level of synapses. Synaptic arrangements between amacrines and interneurons that give rise to regular networks of axon collaterals may explain recent electrophysiological observations of lateral inhibition beneath the insect retina. Neural adaptation mechanisms acting on single retinotopic channels or assemblies of channels can also be referred to reciprocal relationships between receptors and first-order interneurons as well as to centrifugal cells from levels of so-called photopic receptor endings.

https://science.sciencemag.org/content/sci/195/4281/894.full.pdf

Nicholas J. Strausfeld

Papers

Common design in a unique midline neuropil in the brains of arthropods.

Convergence of visual, haltere, and prosternai inputs at neck motor neurons of Calliphora erythrocephala

Neuroarchitectures Serving Compound Eyes of Crustacea and Insects

The evolution of crustacean and insect optic lobes and the origins of chiasmata

Vision in insects: pathways possibly underlying neural adaptation and lateral inhibition