Zoraptera are a cryptic and enigmatic group of insects. The species diversity is lower than in
almost all other groups of Hexapoda, but may be distinctly higher than presently known …

Intromittent organs—structures that place gametes into a mate for internal fertilization—
evolved many times within the animal kingdom, and are remarkable for their extravagant …

The radula, a chitinous membrane spiked with teeth, is the molluscan autapomorphy for the
gathering and processing of food. The teeth, as actual interfaces between the organism and …

No consensus exists for the homology and terminology of the male genitalia of the
Hexapoda despite over a century of debate. Based on dissections and the literature, genital …

The gastric mill of Decapoda is a unique feature, which comprises teeth, stabilizing ossicles,
and particle sorting setae. Involved in the fragmentation and sorting of the food, this structure …

Coevolution of male and female genitalia is widespread in animals. Nevertheless, few
studies have examined the mechanics of genital interactions during mating. We …

Spiral, one of the most well-known functional patterns in nature that can be observed in
structures such as the proboscis of lepidoptera and snail shells or as vortices forming in …

Hyper-elongated structures and their penetration are widespread among insects, for
example, intromittent organs, ovipositors, and piercing-sucking mouthparts. The penetration …

Geometry and material are two key factors that determine the functionality of mechanical
elements under a specific boundary condition. Optimum combinations of these factors fulfil …

The distal leg structures of Zoraptera are documented and discussed with respect to their
functional morphology and evolutionary aspects. We investigated eight species using …