Blood-sucking ticks might be even clingier than we thought. Recent research has found that at least one tick species seems to use static electricity to help itself grapple onto potential hosts. The trick allows the tick to extend its reach by several body lengths, the authors say.
Ticks are tiny parasitic arachnids, though they’re more closely related to mites than spiders. As a rule, ticks need to feed on the blood of other animals to survive. And it’s this same way of life that makes them a prolific vector for spreading many diseases to their hosts, humans included. Every year in the U.S., almost a half million people are estimated to contract Lyme disease, the most common tickborne germ in the country.
Despite their similarity, the vampiric bugs aren’t capable of flight or even jumping. To reach their prey, many species will engage in a behaviour known as questing, which basically means that they’ll climb up a leaf or other vegetation and grab onto a host when the animal brushes alongside it. But a team of researchers in the UK has theorised that ticks aren’t just relying on direct contact to finagle themselves into prime feeding position — they’re also using electrostatic forces.
In a study published over the weekend in the journal Current Biology, the researchers have presented multiple lines of evidence, including lab experiments, for their theory. They focused on studying young castor bean ticks (Ixodes ricinus), a common source of Lyme and other diseases in Europe.
In one experiment, for instance, they electrostatically charged animal fur, then found that the ticks could be pulled to the fur within short distances. In another experiment, they showed that ticks could be attracted to electrodes tweaked to mimic the electric field of a potential host, allowing the ticks to be lifted across air gaps. They also found that the natural interaction between animals and surrounding vegetation can produce strong electric fields and that the ticks can be equally attracted to both positive and negative voltages, likely increasing the opportunities for this trick to happen.
The static boost might only extend the ticks’ ability to reach a host by a few millimetres, but that’s still several more body lengths than they would normally be capable of achieving. In human terms, that’s “the equivalent of us jumping three or four flights of stairs in one go,” lead study author Sam England, an ecologist at Berlin’s Natural History Museum, told the Associated Press.
Other scientists will have to replicate the findings of England and his team before they become widely accepted. But should this research pass muster, we might eventually learn that ticks aren’t the only ones using static electricity to their benefit. The team speculates that this ability might be widespread among all kinds of parasites that invade the skin, including fleas, lice, and other mites.