Light-mimicking cockroaches indicate Tertiary origin of recent terrestrial luminescence

Physiology of environmental adaptations and resource acquisition in cockroaches

Cockroaches are a group of insects that evolved early in geological time. Because of their antiquity, they for the most part display generalized behavior and physiology and accordingly have frequently been used as model insects to examine physiological and biochemical mechanisms involved with water balance, nutrition, reproduction, genetics, and insecticide resistance. As a result, a considerable amount of information on these topics is available. However, there is much more to be learned by employing new protocols, microchemical analytical techniques, and molecular biology tools to explore many unanswered questions.

Eco-evo bioluminescence on land and in the sea

This review discusses the evolution of bioluminescence organisms that inhabit various environments based on the current understanding of their unique ecologies and biochemistries. As shown here, however, there are still many unanswered questions regarding the functions and mechanisms of bioluminescence, which should be investigated in further studies. To facilitate future research in this field, we introduce our recent attempt, the bioluminescent organism DNA barcode initiative. This genetic reference library will provide resources for other scientists to efficiently identify unstudied bioluminescent organisms, focus their biochemical and genetic research goals, and will generally promote bioluminescence as a field of scientific study.

Cockroaches probably cleaned up after dinosaurs

Dinosaurs undoubtedly produced huge quantities of excrements. But who cleaned up after them? Dung beetles and flies with rapid development were rare during most of the Mesozoic. Candidates for these duties are extinct cockroaches (Blattulidae), whose temporal range is associated with herbivorous dinosaurs. An opportunity to test this hypothesis arises from coprolites to some extent extruded from an immature cockroach preserved in the amber of Lebanon, studied using synchrotron X-ray microtomography. 1.06% of their volume is filled by particles of wood with smooth edges, in which size distribution directly supports their external pre-digestion. Because fungal pre-processing can be excluded based on the presence of large particles (combined with small total amount of wood) and absence of damages on wood, the likely source of wood are herbivore feces. Smaller particles were broken down biochemically in the cockroach hind gut, which indicates that the recent lignin-decomposing termite and cockroach endosymbionts might have been transferred to the cockroach gut upon feeding on dinosaur feces.

Luminescence Phenomena: An Introduction

Luminescence is "cold light", light from other sources of energy, which can take place at normal and lower temperatures. There are several varieties of luminescence, each named according to what the source of energy is, or what the trigger for the luminescence is. Luminescence is a collective term for different phenomena where a substance emits light without being strongly heated, i.e., the emission is not simply thermal radiation. This definition is also reflected by the term "cold light".