What Good Are Ticks?

3 Reasons We Should Tolerate Ticks

Deer tick.
What good are ticks?. Getty Images/Robert Trevis-Smith

There may be no “bug” creepier than a tick. These blood-sucking parasites crawl up our bodies, embed their mouthparts in our skin, and then casually drink their fill of our blood, until their bodies expand like tiny water balloons. Ticks carry and transmit a variety of diseases to people and pets, from Lyme disease to anaplasmosis. Feeding ticks can paralyze livestock, and large tick infestations can kill the host animal.

So as you carefully pluck a tick from your skin, you may undoubtedly wonder what purpose they serve? What good are ticks, exactly?

Ticks Are Ancient Arthropods

First, consider the tick's long history on earth. Though it might be hard to see from our perspective as a blood host, ticks do serve an important role in the ecological system. Every organism serves a purpose, and the lowly tick is no exception.

Parasitic ticks first appear in the fossil record during the Cretaceous period, and it’s believed they were the bane of dinosaurs millions of years before they bothered us. The oldest known fossil tick was discovered in a piece of amber recovered from a vacant lot in Sayreville, NJ. Carlos Jerseyi, as the specimen was named, is 90 million years old, and may have come to NJ by hitching a ride with a seabird that migrated from South America. Despised though they might be, ticks are clearly doing something right to have survived this long.

3 Reasons We Should Tolerate Ticks

So, why do we need ticks? First, and perhaps most obvious, ticks are food for other animals. Reptiles, amphibians, and birds all consume ticks in quantity. The awful arachnids are an essential food source for animals that forage for sustenance in the places where ticks live (which is almost everywhere, really).

In areas that are thick with ticks, in fact, people will sometimes deploy guinea hens as a roaming tick control team. And the neighborhood opossums that wander through your yard after dark are doing their part, too. Opossums eat a remarkable number of ticks.

Second – and this may not help ticks gain your support – ticks host a remarkable variety of other organisms, namely micro-parasites. Ticks carry viruses, bacteria, protozoa, and other microscopic life wherever they go. While we’d prefer that they didn’t, since many of these stowaways are the very source of our tick-borne illnesses, in the grand, ecological scheme of things these microorganisms are part of the diversity of life on Earth. Ask the virus that lives within the tick why we need the tick.

And third, by virtue of their blood-draining and disease-causing ways, ticks help control the populations of their larger hosts. We understand concepts like carrying capacity and population control when we study predator-prey relationships, but we are less sympathetic to the tiny parasites that serve the same purpose. Just as the owl keeps the population of mice and shrews in check, ticks play a role in maintaining a balance within the ecosystem.

Regardless of whether the giraffe is taken down by the lion or by the blood-draining feast of 50,000 ticks (and that is the record for the number of ticks on a single, small giraffe), it’s still one less giraffe in the herd.

Don’t hate the ticks, they’re just doing what they’ve been doing for tens of millions of years. If you don’t want them feeding on you, be sure to take precautions to avoid tick bites.

Sources:

  • Ancient Tick Found In New Jersey Leaves Experts Guessing, Ohio State University media release, March 27, 2001. Accessed online May 28, 2013.
  • Encyclopedia of Entomology, 2nd edition, edited by John L. Capinera.
  • Ticks - Integrated Pest Management Manual, National Park Service website. Accessed May 28, 2013.