Abstract
Spiders are known for producing specialized fibers. The radial orb-web, for example, contains tough silk used for the web frame and the capture spiral consists of elastic silk, able to stretch when prey impacts the web. In concert, silk proteins and web geometry affects the spider’s ability to capture prey. Both factors have received considerable research attention, but next to no attention has been paid to the influence of fiber processing on web performance. Cribellate spiders produce a complex fiber alignment as their capture threads. With a temporally controlled spinneret movement, they connect different fibers at specific points to each other. One of the most complex capture threads is produced by the southern house spider, Kukulcania hibernalis (Filistatidae). In contrast to the so far characterized linear threads of other cribellate spiders, K. hibernalis spins capture threads in a zigzag pattern due to a slightly altered spinneret movement. The resulting more complex fiber alignment increased the thread’s overall ability to restrain prey, probably by increasing the adhesion area as well as its extensibility. Kukulcania hibernalis' cribellate silk perfectly illustrates the impact of small behavioral differences on the thread assembly and, thus, of silk functionality.
Highlights
Spiders are known for producing specialized fibers
For example, the tough dragline silk is used for the production of the radial frame, but the capture spiral consists of more elastic silk, which is able to stretch rather than brake when prey is impacting the web[7]
Since we know that the mechanical performance is influenced by the threads’ structure, we asked: How can the much larger K. hibernalis capture enough prey, if its adhesive strength is predicted to be inferior to that of U. plumipes? Is a looped 3D structure enough? Or are there some hidden structural features that enable the capture of larger prey? If so, what are the inherited behavioral differences associated with the production? To answer these questions, we evaluated the ability of K. hibernalis’ threads to restrain prey and combined these data with the analysis of their capture thread assembly
Summary
Spiders are known for producing specialized fibers. The radial orb-web, for example, contains tough silk used for the web frame and the capture spiral consists of elastic silk, able to stretch when prey impacts the web. Most studies so far have tried to understand the capture thread production of cribellate uloborid spiders, as they produce very simple structured capture threads[17,20,21] These threads consist of two parallel axial fibers as core fibers, produced by pseudoflagelliform spigots[17,20], absorbing most of the energy during prey capturing[22]. The final puffy structure of the thread is produced by a comb on the metatarsus of the fourth leg, the calamistrum, probably influencing the protein conformation when brushing over the freshly extracted nanofibers[17,23] As this is a rather linear alignment of fibers in the thread, this thread assembly can abstractly be described as 2D-structure. If one excludes the elasticity data of uloborids’ cribellate capture threads, only two cribellate species (P. otwayensis and Deinopis spinosa) remain showing a much greater extensibility (~680%)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
