My brothers pictures of an Orb Weaver in his CA yard
Orb-weaver spider
Orb-weaver spiders are members of the spider family Araneidae. They are the most common group ofbuilders of spiral wheel-shaped websoften found in gardens, fields, and forests. The English word "orb" can mean "circular",[1] hence the English name of the group. Araneids have eight similar eyes, hairy or spiny legs, and no stridulatingorgans.
Diversity: 186 genera, 3108 speciesThe family has a cosmopolitan distribution, including many well-known large or brightly colored garden spiders. With 3,108 speciesin 186 genera worldwide, the Araneidae comprise one of the largest family of spiders (with the Salticidae and Linyphiidae).[2] Araneid webs are constructed in a stereotypical fashion, where a framework of nonsticky silk is built up before the spider adds a final spiral of silk covered in sticky droplets.
Generally, orb-weaving spiders arethree-clawed builders of flat webswith sticky spiral capture silk. The building of a web is an engineering feat, begun when the spider floats a line on the wind to another surface. The spider secures the line and then drops another line from the center, making a "Y". The rest of the scaffolding follows with many radii of nonsticky silk being constructed before a final spiral of sticky capture silk.The third claw is used to walk on the nonsticky part of the web.Characteristically, the prey insect that blunders into the sticky lines is stunned by a quick bite, and then wrapped in silk..
Much of the orb-spinning spiders' success in capturing insects depends on the web not being visible to the prey, with the stickiness of the web increasing the visibility, thus decreasing the chances of capturing prey.
Many orb-weavers build a new web each day. Most orb-weavers tend to be active during the evening hours; they hide for most of the day. Generally, towards evening, thespider consumes the old web, rests for about an hour, then spins a new web in the same general location.
Some orb-weavers do not build webs at all. Australia produce sticky globules, which contain a pheromoneanalog. The globule is hung from a silken thread dangled by the spider from its front legs. The pheromone analog attracts male moths of only a few species. In the Araneus diadematus, variables such as wind, web support, temperatures, humidity, and silk supply all proved to be variables in web construction. When studied against the tests of nature, thespiders were able to decide what shape to make their web, how many capture spirals, or the width of their web.[6]
Though it could be expected for these spiders to just know these things, it isn't well researched yet as to just how the arachnid knows how to change their web design based on their surroundings. Some scientists suggest that it could be through the spider's spatial learning on their environmental surroundings and the knowing of what will or won't work compared to natural behavioristic rules.[7].
One feature of the webs of some orb-weavers is the stabilimentum, a crisscross band of silk through the center of the web. It is found in several genera, but Argiope – the yellow and banded garden spiders of North America – is a prime example. As orb-weavers age, they tend to have less production of their silk;many adult orb-weavers can then depend on their coloration to attract more of their prey.[8]The band may be a lure for prey, a marker to warn birds away from the web, and a camouflage for the spider when it sits in the web. The stabilimentum may decrease the visibility of the silk to insects, thus making it harder for prey to avoid the web.[9] The orb-web consists of a frame and supporting radii overlaid with a sticky capture spiral, and the silks used by orb-weaver spiders have exceptional mechanical properties to withstand the impact of flying prey.[10] The orb-weaving spider Zygiella x-notataproduces a unique orb-web with a characteristic missing sector, similar to other species of the Zygiella genus in the Araneidae family.[11].The capacity of orb–webs to absorb the impact of flying preyled orbicularian spiders to become the dominant predators of aerial insects in many ecosystems.[14] Some Metepiera species are semisocial and live in communal webs. In Mexico, such communal webs have been cut out of trees or bushes and used for living fly paper.[citation needed] In 2009, workers at a Baltimore wastewater treatment plant called for help to deal withover 100 million orb-weaver spiders, living in a community that managed to spin a phenomenal web that covered some 4 acresof a building, with spider densities in some areas reaching 35,176 spiders per cubic meter.[16]
(1 cubic metre = 1000 litres (exactly)[2][3]) ≈ 35.3 cubic feet
https://en.m.wikipedia.org/wiki/Orb-weaver_spider