As arachnid superorders go, ticks are pretty evolutionarily successful. They’ve been around for at least 100 million years in one variety or another, with their main party trick – hanging around until they can latch a host to feed on – working on thousands of different animals across almost endless environments. But how concerned should you be about them in the UK? You won’t miss the blood they take, but they can cause a variety of unpleasant conditions in their hosts – and there’s some evidence that their population is growing.
Just so we’re all on the same page, there are at least 900 species of ticks currently operating across every continent – some targeting seabirds and lizards, others cattle or dogs. Ticks sense vibrations and body heat, and will find a good place to wait for a host, then latch on to it, finding a patch of skin where the animal’s blood vessels run close to the surface and where it’s hard to be scratched away. At this point, it digs in and inserts its barbed, tubular mouthpart – sometimes secreting attachment “cement” to make itself harder to remove. In between slurps, it squirts saliva into the wound, containing a protein that prevents the host’s blood from clotting.
