Did you know that some animals are notorious hitchhikers? The phenomenon known as “phoresy” is when one organism attaches itself to another to catch a ride, and perhaps no animals have been hitchhiking as long as pseudoscorpions.
Pseudoscorpions are arachnids that occupy an order separate from their cousins spiders and scorpions. Pseudoscorpions resemble ticks but have massive, crab-like front claws that make them deceptively frightening given that they only tend to be a few millimeters long. The oldest pseudoscorpion fossils are 390 million years old, and they haven’t really changed much since then. Nor has their behavior. Scientists have found pieces of amber millions of years old with pseudoscorpions attached to another organism exactly as they do today.
Because they are so small, predators and weather conditions can make travel dangerous for them. Pseudoscorpions use phoresy to avoid some of these dangers, latching onto bigger, stronger creatures for transportation. Phoresy is especially helpful because many species of pseudoscorpions live in places such as decaying logs and under decaying leaves. So, when the habitat becomes inhospitable, they wait until a fly or some other creature comes by, grab onto their legs, and get a lift, free of charge.
The behavior doesn’t affect the hosts who give them rides, and from a human perspective, this behavior can actually be beneficial. Pseudoscorpions often find their way into houses through phoresy and will make themselves comfortable by eating bed bugs, carpet beetles, and other creatures that cause damage to our homes and belongings. So, while hitchhiking might not seem advisable, in the animal world, it seems like it can sometimes be a good thing.
Special thanks to Mark Harvey, Western Australian Museum for revieiwng today's episode.
Learn more
Sources Pseudoscorpions, University of Minnesota
Hitchhiking Pseudoscorpions, Common Naturalist
Pseudoscorpions: the Strangest Arachnids? Bug Eric, Blogspot
