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Updated on: July 21st, 2026
The Tin Man in the Wizard of Oz sang that getting one would make him “kind of human,” but most animals have a heart, even if they’re not quite the same as the ones that beat in our chests.
Read on to find out about the chambers of the heart, why insects have a different system and why insect anatomy matters in pest control…
Insects have an open circulatory system, in which a dorsal vessel acts as both a heart and an aorta, pumping a fluid called hemolymph through a single tube towards the head. Once released near the head, the hemolymph flows freely through the body cavity, known as the hemocoel, directly delivering nutrients and hormones to the internal organs.
This system is not the main way insects transport oxygen. That’s done by a network of tracheal tubes delivering air directly to the insect’s tissues.
To make a comparison, we’ll say that a “heart” is any bodily organ that circulates blood around an animal’s body. That’s because a four-chamber heart that we have isn’t the only way it forms in other living creatures. Plus, all the veins and arteries extending out to our limbs—not all animals have those either.
Generally, insects have much simpler circulatory systems than us. They have no veins or arteries. Their hearts are not as complex as ours. They don’t have four chambers, but one. It’s located in their abdomen and pumps blood through their open circulatory system.
Insects don’t need blood vessels, partly because they have a kind of armor on the outside of their bodies. We humans have our skeletons on the inside. Insects have exoskeletons, so their ‘bones’ are on the outside. That allows them to push blood throughout their bodies to collect and distribute oxygen (that’s the main purpose of blood in any creature).
Want to know something else that insects are missing? Lungs.
An insect's entire anatomy, including its open circulatory system, is designed to support its specific physical needs and environmental interactions. Their open design means insects can be flexible and lightweight: vital for them to fly and move through tight spaces.
Their exoskeletons mean most insects maintain a fairly consistent, rigid shape throughout their lives, except for those that molt—they live through multiple forms.
We look at many small details like how insects circulate blood or what kinds of organs they have or don’t have. Because if we understand a pest’s anatomy, we can implement precise, species-specific treatments to maximize control and minimize environmental impact.
Knowing their exoskeleton helps us select pesticides that penetrate or erode protective waxes
Understanding their respiratory system’s spiracles means we can use suffocants or dusts
Identifying their specific chewing or piercing-sucking mouthparts helps us know whether baiting or contact sprays will be more effective
Knowing their circulatory and nervous systems means our treatments reach their vital organs.
That’s also why we go through such extensive training to learn all the nitty-gritty stuff before we’re certified to go out into the world and treat a home or business for pests. It’s why we have a comprehensive pest control training program for all our new hires, taught by our resident entomologist, Dr. Gary.
Got bugs? Get JP Pest Solutions. We offer expert professional help to identify the source, so we eradicate not just the pests you see, but also their nests. Plus, we provide prevention solutions to keep bugs out of your home.
Interested in learning more fun pest facts? Check out our blog to learn more about all-things-pest.
Our local technicians will assess your property and recommend tailored solutions. Fast, friendly, and completely obligation-free.