You don’t have to spend much time browsing social media sites before finding a proud pet owner’s picture of their four-legged companion. Nobody has a problem with this because dogs and cats are cute animals that do adorable things. However, some pet owners post pictures of their beloved tarantulas to social media sites as well. Unlike pictures of dogs and cats, many people respond to pictures of tarantulas with horror. It is becoming more and more common for tarantula enthusiasts to post pictures of their pet arachnid’s supposedly cute “paws.” Little do many know, but the tip of a tarantula’s leg resembles a paw of sorts. For example, the “paws” belonging to the pinktoe tarantula are often found pictured and posted on social media sites, as this species of tarantula must have the most picture-worthy feet of any tarantula species, just as their common name would suggest. Of course, tarantulas do not have paws; instead, tarantulas have dense patches of hair called “claw tufts.” Claw tufts are an important feature as they allow bulky tarantulas to climb vertically along a variety of different surfaces.
When compared to other arachnids, tarantulas are relatively heavy. In order to support their weight and the weight of their prey while climbing vertical surfaces, a tarantula’s hairy feet adhere to many surfaces. These hairs are visible to the human eye, but each visible hair is covered with hundreds of thousands of smaller hairs called “setules.” Setules are so small that an electron microscope is required to see them. The heavier the tarantula species, the more setules it has. For example, researchers found that a species of jumping spider known as Evarcha arcuata has a total of 600,000 setules, which is necessary for this species as it hunts and carries prey regularly up vertical surfaces. Smaller arachnids do not possess the hairy claw tufts that tarantulas possess because their low body weight does not require dense patches of setules. However, the relatively small huntsman and jumping spiders possess setules, as they are the only spider groups that are capable of crawling upside down along a ceiling while carrying prey as large as a toad in their fangs.
Have you ever found a spider crawling along your ceiling?