Why Ants Are Attracted to Blood - The Surprising Reasons

Unraveling the Mystery: Why Do Ants Like Blood?

Ants are constantly scavenging for food, and they seem especially attracted to sugary and protein-rich substances. This can lead ants to invade picnics, kitchens, and even bite or sting humans and animals to get to the nutrients in blood. But why exactly are ants drawn to blood? The reasons behind this gruesome ant behavior are complex and shed light on their biology and ecology.

Ants Require Protein

Ants are omnivores and require a balanced diet of carbohydrates, lipids, and protein to survive. Protein provides nutrients needed for growth, development, and reproduction. Lacking a steady protein source can impair ant colony growth.

Blood provides an excellent source of protein through blood plasma and hemoglobin inside red blood cells. Mammalian blood is particularly protein rich - human blood is 14% protein by weight. Ants likely evolved to target blood as a dense, readily available protein supplement.

Attracted to Blood Chemicals

Ants use chemoreceptors on their antennae and mouthparts to detect food sources. Specific chemicals in blood stimulate these chemoreceptors and attract ants.

Plasma proteins and nitrogenous waste like urea emit volatile chemicals that signal a protein meal. Iron-containing hemoglobin also produces a distinct odor. Furthermore, blood emits carbon dioxide as it degrades, which ants can detect.

Opportunistic Foraging

Ants have opportunistic feeding habits and collect any food they encounter. If ants stumble upon a bleeding animal, they immediately mobilize to collect the nutritious blood before it goes to waste. Ants use pheromone trails to quickly recruit nestmates to transport the food back to the colony.

This opportunism allows ant colonies to thrive on ephemeral, scattered resources. It also makes ants persistent around wounds and sores seeping blood - they painstakingly gather every last drop.

Attracted by Sugar Too

While the protein in blood attracts ants, they also gather it for the glucose it contains. Blood glucose levels range from 60-140 mg/dL - a significant sugar source. Ants need dietary sugars and carbohydrates for energy.

Hearty blood meals provide ants both protein for growth and sugars for immediate energy. This combination makes blood an ideal ant food.

Do All Ants Bite for Blood?

The vast majority of ants do not consume blood. Out of over 12,000 ant species, only a few groups like bull ants and army ants actively bite or sting other animals to drink blood.

Army ants are particularly notable for their swarm raids on small animals to draw blood. But most ants get protein from dead insects, seeds, and honeydew secretions from sap-sucking bugs.

Biting vs. Stinging Ants

Ants have two main ways to get through skin to access blood:

• Biting - Mandibles cut through skin.
• Stinging - Ovipositor injects venom.

Biting ants like bull ants have large, powerful mandibles designed to slice through flesh. Stinging ants have modified egg-laying structures (ovipositors) that inject painful venom.

Stinging ants belong to the subfamily Myrmicinae, including fire ants. When they sting, they anchor themselves in place with mandibles and sting repeatedly.

Why Do Ant Bites/Stings Hurt?

The pain and injury from ant bites/stings comes from two sources:

1. Mechanical damage - Mandibles and ovipositors pierce tissue.
2. Toxic venom - Stinging ants inject venom through ovipositors.

Bull ant mandibles are serrated like steak knives, causing intense pain and tearing. Stinging ant venom contains toxic alkaloid chemicals that damage cells and cause localized pain.

Risks of Ant Bites/Stings

For most people, ant bites and stings cause minimal lasting harm. But they can pose greater risks for:

• Children
• Elderly
• Those with allergies/weak immune systems

Severe allergic reactions like anaphylaxis rarely occur with ant stings. But the toxic venom can be dangerous in those with compromised immunity. Multiple stings increase toxicity.

Symptoms of Ant Bites and Stings

Typical symptoms at the wound site include:

• Instant, sharp pain
• Itching, burning sensation
• Red bump or welt
• Swelling
• Small, fluid-filled blister

General allergic reaction symptoms may follow:

• Hives, itchy rash
• Swelling in other body parts
• Wheezing or breathing difficulty
• Dizziness, fainting
• Nausea, vomiting, diarrhea

See a doctor immediately if severe symptoms appear, especially trouble breathing.

Treatment for Ant Bites and Stings

Following prompt first aid can minimize ant bite/sting symptoms:

1. Wash with soap and water.
2. Apply cold pack to reduce swelling.
3. Avoid scratching the wound.
4. Apply hydrocortisone cream/calamine lotion to ease itching.
5. Take antihistamine containing diphenhydramine.
6. Use OTC pain reliever if needed.

See a doctor for severe reactions, multiple stings, signs of infection, or venom reactions in high-risk individuals.

Preventing Ant Bites and Stings

You can take proactive measures to avoid attracting ants and getting bitten or stung:

• Clean up food spills, crumbs, and residues after eating.
• Store food in sealed containers.
• Use ant baits and traps around the home.
• Wear shoes outdoors in grassy areas.
• Shake out clothing and shoes before wearing.
• Avoid disturbing or provoking ant mounds.
• Seal cracks and openings where ants enter buildings.

Why Blood? Evolutionary Ant Mysteries

While ants' attraction to blood made sense from an ecological perspective, mysteries remained around how it evolved. Recent genetics research has shed light on ant hematophagy origins.

Scientists discovered the major group of stinging, blood-feeding ants - Leptanillinae - evolved this behavior only once early in their ancestry. All extant blood-drinking ants descend from this ancient common ancestor.

This ant lineage developed specific genetic adaptations like salivary proteins to consume blood. The behavior likely evolved to capitalize on an abundant but competitive nutrient source before spreading to various descendent species.

DNA studies continue to reveal the evolutionary pathways and genetic tricks enabling ants to survive on such peculiar diets as blood.

Avoiding Unwanted Ant Attention

Blood, sweat, and skin oils attract curious ants. To dodge ant bites and stings:

• Clean and cover wounds to avoid attracting ants.
• Rinse off after exercise to remove sweat.
• Shower after swimming to wash off skin secretions.
• Avoid walking barefoot outdoors.
• Manage diabetes and reduce blood sugar levels.

Controlling ants around your home also reduces unwanted interactions. Target ant nests and trails with baits or insecticides if needed. With some diligence, we can appreciate ants at a distance without becoming their next meal.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.