Ecophysiology Of Spiders

With over 43,000 species, spiders are the largest predacious arthropod group. They have developed key characteristics such as multi-purpose silk types, venoms consisting of hundreds of components, locomotion driven by muscles and hydraulic pressure, a highly evolved key-lock mechanism between the complex genital structures, and many more unique features. After 300 million years of evolutionary refinement, spiders are present in all land habitats and represent one of the most successful groups of terrestrial organisms. Ecophysiology combines functional and evolutionary aspects of morphology, physiology, biochemistry and molecular biology with ecology. Cutting-edge science in spiders focuses on the circulatory and respiratory system, locomotion and dispersal abilities, the immune system, endosymbionts and pathogens, chemical communication, gland secretions, venom components, silk structure, structure and perception of colours as well as nutritional requirements. Spiders are valuable indicator species in agroecosystems and for conservation biology. Modern transfer and application technologies research spiders and their products with respect to their value for biomimetics, material sciences, and the agrochemical and pharmaceutical industries.

Recently another book on insect physiology was published. It was restricted to a few focal points as are many of these new insect physiology books, but there was considerable depth in its specialized point of view. We were dis cussing the structure of this book and of insect physiology books, in general, when Prof. Remmert asked me " . . . and what about books on spider physio logy?" Silence. Then I started to explain "oh yes, there is a congress pro ceedings volume on this topic and there is a group with excellent publica tions on another topic . . . ", but I felt that this answer was weak. One can no longer buy the proceedings volume in a bookshop and to read a series of publications on a given topic one must search in a library for a dozen journals. Why is there not a single book on spider physiology comparable with the many books on insect physiology? Are spiders a scientific ivory tower, far from public interest and commercial importance? I do not think so, although spiders are one of the many "forgotten" animal groups which always grew in the shadow of the insects. There are research groups working on spider physiology, there are fascinating phenomena in this animal group and there are plenty of exciting results. Spiders may have been always underresearch ed, but research is progressing. In the last few years, new books have been published, e. g.

One of the only books to treat the whole spider, from its behavior and physiology to its neurobiology and reproductive characteristics, Biology of Spiders is considered a classic in spider literature. First published in German in 1979, the book is now in its third edition, and has established itself as the supreme authority on these fascinating creatures. Containing five hundred new references, this book incorporates the latest research while dispelling many oft-heard myths and misconceptions that surround spiders. Of special interest are chapters on the structure and function of spider webs and silk, as well as those on spider venom. A new subchapter on tarantulas will appeal especially to tarantula keepers and breeders. The highly accessible text is supplemented by exceptional, high-quality photographs, many of them originals, and detailed diagrams. It will be of interest to arachnologists, entomologists, and zoologists, as well as to academics, students of biology, and the general reader curious about spiders.

In this lavishly illustrated, first-ever book on how spider webs are built, function, and evolved, William Eberhard provides a comprehensive overview of spider functional morphology and behavior related to web building, and of the surprising physical agility and mental abilities of orb weavers. For instance, one spider spins more than three precisely spaced, morphologically complex spiral attachments per second for up to fifteen minutes at a time. Spiders even adjust the mechanical properties of their famously strong silken lines to different parts of their webs and different environments, and make dramatic modifications in orb designs to adapt to available spaces. This extensive adaptive flexibility, involving decisions influenced by up to sixteen different cues, is unexpected in such small, supposedly simple animals. As Eberhard reveals, the extraordinary diversity of webs includes ingenious solutions to gain access to prey in esoteric habitats, from blazing hot and shifting sand dunes (to capture ants) to the surfaces of tropical lakes (to capture water striders). Some webs are nets that are cast onto prey, while others form baskets into which the spider flicks prey. Some aerial webs are tramways used by spiders searching for chemical cues from their prey below, while others feature landing sites for flying insects and spiders where the spider then stalks its prey. In some webs, long trip lines are delicately sustained just above the ground by tiny rigid silk poles. Stemming from the author’s more than five decades observing spider webs, this book will be the definitive reference for years to come.

Spiders, objects of eternal human fascination, are found in many places: on the ground, in the air, and even under water. Leslie Brunetta and Catherine Craig have teamed up to produce a substantive yet entertaining book for anyone who has ever wondered, as a spider rappelled out of reach on a line of silk, “How do they do that?” The orb web, that iconic wheel-shaped web most of us associate with spiders, contains at least four different silk proteins, each performing a different function and all meshing together to create a fly-catching machine that has amazed and inspired humans through the ages. Brunetta and Craig tell the intriguing story of how spiders evolved over 400 million years to add new silks and new uses for silk to their survival “toolkit” and, in the telling, take readers far beyond the orb. The authors describe the trials and triumphs of spiders as they use silk to negotiate an ever-changing environment, and they show how natural selection acts at the genetic level and as individuals struggle for survival.

My initial interest in the Solifugae (camel-spiders) stems from an incident that occurred in the summer of 1986. I was studying the behavioral ecology of spider wasps of the genus Pepsis and their interactions with their large theraphosid (tarantula) spider hosts, in the Chihuahuan Desert near Big Bend National Park, Texas. I was monitoring a particular tarantula burrow one night when I noticed the resident female crawl up into the burrow entrance. Hoping to take some photographs of prey capture, I placed a cricket near the entrance and waited for the spider to pounce. Suddenly, out of the comer of my eye appeared a large, rapidly moving yellowish form which siezed the cricket and quickly ran off with it until it disappeared beneath a nearby mesquite bush. So suddenly and quickly had the sequence of events occurred, that I found myself momentarily startled. With the aid of a headlamp I soon located the intruder, a solifuge, who was already busy at work macerating the insect with its large chelicerae (jaws). When I attempted to nudge it with the edge of my forceps, it quickly moved to another location beneath the bush. When I repeated this maneuver, the solifuge dropped the cricket and lunged at the forceps, gripping them tightly in its jaws, refusing to release them until they were forcefully pulled away.