Transcript:

Today on Animal Fact Files we’re discussing common house spiders. The information in this video is specific to this species, but they look similar to their family members (Theridiidae) so you’ll see some of them appear in this video— they’re also known as tangle-web spiders, cobweb spiders, and comb-footed spiders. The common house spider gets its name because it is commonly seen in people's homes. These invertebrates almost exclusively live in close proximity to humans; they're a synanthropic species! They take up residence in barns, sheds, basements, and more, constructing loose, tangled webs in ceiling corners and eves. Although common house spiders have a cosmopolitan distribution, they're believed to have originated in South America. It's likely they traveled the world on native plant species sent around the globe by humans, so now the spiders live just about everywhere! 

It's not always easy to tell a common house spider from their family members, which is part of why we decided to showcase the entire family in this video. This species and its congeners typically have a teardrop shaped abdomen and downward facing spinnerets; those are the silk-producing glands on their rear end. The common house spider is typically brown to yellow in color with yellow bands around its legs; however, it's worth mentioning that even black widows are part of this spider family and those are often confused with other spider species, so it's not uncommon for misidentification to occur. Of course, mention of a relation to black widows might give a false impression of the common house spider. While black widows are feared for their medically significant bite, common house spiders don't have the kind of potency as they're family members. Common house spiders are considered harmless and a bite from them won't cause any issues other than some pain (unless you're allergic).

Common house spiders are small in size with females reaching up to 8 millimeters in length and males maxing out at about half this. The males are smaller, but they don't have to worry about cannibalism. Common house spider couples share their webs with the male living alongside the female during the mating season. In warmer parts of their range, adults of these spiders are present year round! They can even form aggregations where their messy webs entangle with those of their neighbors. Common house spiders catch insect prey like flies and grasshoppers on their sticky silk.

While you may have never noticed a common house spider, I would bet that you've probably witnessed one of their egg sacs. These are brown and papery, often appearing far larger than the female who made them. Inside, a few dozen to over 300 eggs develop. The babies remain in their mother's web for their first few days of life before ballooning to travel elsewhere. Ballooning Is when young spiders let out a thread of silk and ride the wind whatever it takes them. Most don't survive, but those that do can live more than a year as adults!

Common house spiders tend to enjoy the benefits of human-dwelling living by avoiding many predators in the outside world, such as birds and small mammals. Of course, humans tend to be fairly intolerant of the spider's presence regardless of the benefit they provide people by keeping their home free of other unwanted visitors. House pets, like cats, can also cause some problems for the common house spider. Thankfully for them, and for us, cats can't fly!

For more facts on common house spiders, check out the links below. Give a thumbs up if you learned something new today. Thank you to our Patrons SpikeSpiegel93, Dad, and everyone else for their support of this channel! And thank you for watching Animal Fact Files!