Mapping the Auditory Space of Female Mosquitoes in 3D.

The task of directional hearing faces most animals that possess ears. They approach this task in different ways, but a common trait is the use of binaural cues to find the direction to the source of sound. In insects, the task is further complicated by their small size and, hence, minute temporal and level differences between two ears.

Beyond the Limits of Light: An Application of Super-Resolution Confocal Microscopy (sCLSM) to Investigate Eocene Amber Microfossils.

Amber is known as one of the best sources of fossil organisms preserved with exceptional fidelity. Historically, different methods of imaging have been applied to amber, including optical microscopy and microtomography. These methods are sufficient to resolve millimeter-scaled fossils.

A transitional fossil mite (Astigmata: Levantoglyphidae fam. n.) from the early Cretaceous suggests gradual evolution of phoresy-related metamorphosis.

Metamorphosis is a key innovation allowing the same species to inhabit different environments and accomplish different functions, leading to evolutionary success in many animal groups. Astigmata is a megadiverse lineage of mites that expanded into a great number of habitats via associations with invertebrate and vertebrate hosts (human associates include stored food mites, house dust mites, and scabies). The evolutionary success of Astigmata is linked to phoresy-related metamorphosis, namely the origin of the heteromorphic deutonymph, which is highly specialized for phoresy (dispersal on hosts).

Frequency tuning of swarming male mosquitoes (Aedes communis, Culicidae) and its neural mechanisms.

The primary function of hearing in mosquitoes is believed to be intraspecific communication. This view dictated the principle of many behavioral studies, namely, the attraction of male mosquitoes to the sounds that mimicked a female tone. However, after the avoidance response to certain frequencies of sound was demonstrated, it became clear that attraction tests cannot fully account for all the capabilities of the mosquito auditory system.

Directional and frequency characteristics of auditory neurons in male mosquitoes.

The paired auditory organ of the mosquito, the Johnston's organ (JO), being the receiver of the particle velocity component of sound, is directional by its structure. However, to date almost no physiological measurements of its directionality have been made. In addition, the recent finding on the grouping of the JO auditory neurons into antiphase pairs demands confirmation by different methods.

Frequency organization of the Johnston's organ in male mosquitoes (Diptera, Culicidae).

The Johnston's organs (JO) of mosquitoes are the most complex mechanosensitive organs yet found in insects. Previous findings on the behavior of mosquitoes suggest that, together with exceptional sensitivity, their auditory system can discriminate frequencies. Analysis of compound responses of the JO did not provide unambiguous evidence of such discrimination, nor did it help to find its mechanism.

Previous motor activity affects the transition from uncertainty to decision making in snails.

One of the most widely accepted benefits of enhanced physical activity is an improvement in the symptoms of depression, including the facilitation of decision making. Up until now, these effects have been shown in rodents and humans only. Little is known about their evolutionary origin or biological basis, and the underlying cellular mechanisms also remain relatively elusive.

Direct and decarboxylation-dependent effects of neurotransmitter precursors on firing of isolated monoaminergic neurons.

To elucidate mechanisms that underlie the profound physiological effects of the monoamine precursors 5-hydroxy-L-tryptophan (5-HTP) and L-3,4-dihydroxyphenylalanine (L-DOPA), we examined their action on single monoaminergic neurons isolated from the ganglia of the gastropod snail Lymnaea stagnalis. In isolated serotonergic PeA motoneurons, 5-HTP produced excitation. The effect was mimicked by serotonin at 0.