So I was recently posed this question: “What is the point of ticks? Seriously, what purpose do they serve?”
Fair question. I have recently joined the field of vector-borne disease, more specifically working with arboviruses (arthropod-borne viruses), which includes such delightful creatures as mosquitoes and ticks. I am currently working with mosquitoes, but ticks are a fairly common carrier of diseases in the US, and certainly worth a bit of digital discussion. When answering this question, I am going to be up front here and say that very little of my explanation is going to endear ticks to you. Quite frankly, if we humans found a way to rid the world of bloodsuckers like ticks and mosquitoes, I would crack open a six pack and sit outside in the evening without using bug spray after taking a long walk through a field of tall grass wearing shorts. Devastating consequences to the ecosystem? Meh. Nature can take one for the team. I would not shed a tear. That being said, these blood-sucking salivary glands with legs (seriously…the salivary glands make up a significant portion of their anatomy) do play a role in ecology. The brief version is this:
- They contribute to biodiversity.
- They consume blood.
- They serve as a food source.
- They carry disease.
Does that answer the question? Oh…you want some explanation or elaboration? *sigh* Fine, fine. I did not have any other plans for my evening.
OK, the first one is pretty self-explanatory, right? I mean, our world is ultimately better off with more biodiversity than less. Think about genetic diversity, and how amazing it is that such a myriad of creatures have evolved on this planet. There are clues and answers to so many of life’s questions and problems just waiting to be found in the genetic information that exists in our world. Who knows what insights we might one day gain from the evolutionary path that these arthropods have taken? They have been around since the dinosaurs walked the earth, so they must be doing something right. Not good enough, though…am I right? That justification can be used for most anything, so what else do we have?
They consume blood. This is actually kinda important, as it ties in with the fact that they also serve as a food source. Here…you can go read a lot of information about them, courtesy of the National Parks Service, if you feel so inclined. Lots of things eat them, especially birds, reptiles, some amphibians, and maybe some other arthropods as well. The thing about consuming blood is that they serve as a intermediary in the food chain, taking energy from larger organisms and conveying it to smaller ones that might not necessarily feed on those larger creatures. Birds are cute, right? It would be a shame if they were constantly trying to prey upon you and drink your blood. Life would be like a Hitchcock film. Instead, they feed on parasites that feed on you, leaving us free to hate the parasite and enjoy the birds.
The final point relates to the role ticks play in contributing to population balance. Many ticks carry pathogenic organisms that like to infect larger organisms, so from the perspective of a virus or a bacteria, ticks are just super! All of us who suffer from the effects of disease-causing organisms would probably like to see them eradicated as well, but the combined role of disease and vector is to curb population growth. Simply put, as the population of the host (human, deer, bird, mouse, whatever) increases, so too does the population of the tick. The ticks spread more disease, more animals get sick and die, or become more susceptible to predation, and the population decreases. As the population decreases, so tick population decreases as well until the population of the host is able to recover. Sorta like the predator/prey relationship. The thing is, none of these relationships happen in isolation from one another. The overall ecological relationships are much more complicated, and influence one another, but hopefully you get the idea.
So that is the purpose of the tick, such as I understand it. If you expected me to fill you with a sense of awe and mystical wonder, giving you cause to reevaluate your opinion of this oft-maligned creature and embrace it as a part of the natural order to which we all belong…well…sorry to disappoint. I am just answering a question. They can be fascinating and we can understand the role that they play in the ecosystem, but I still look forward to the day when I crack open that cold one and drink it down in honor of their memory.