Ladybugs, those small, brightly colored beetles, are a familiar sight in gardens and homes. Their distinctive spotted appearance makes them easily recognizable. Many people wonder what their patterns might reveal about the individual ladybug.
What Ladybug Spots Do Not Indicate
The number of spots on a ladybug does not indicate its age. Ladybugs do not gain or lose spots as they grow older. Most ladybugs have a lifespan of about one year, too short for their spot patterns to change significantly. For example, a ladybug with 24 spots is not 24 years old.
Similarly, the number or size of a ladybug’s spots does not reveal its gender. Both male and female ladybugs of the same species typically exhibit similar spot patterns. The idea that spot patterns might predict future events, such as a harvest or the number of children one might have, is a folk belief not based on scientific fact.
What Ladybug Spots Actually Mean
The number and pattern of spots on a ladybug primarily help identify its species. Over 5,000 species exist worldwide, and their markings can vary significantly. Some ladybug species have no spots at all, while others can have a large number.
For instance, the seven-spotted ladybug (Coccinella septempunctata) is characterized by its orangish-red body with seven black spots, typically one near the thorax and three on each wing case. The two-spotted ladybug (Adalia bipunctata), despite its name, can have variations from two spots to six, or even be entirely black. The Asian lady beetle (Harmonia axyridis) exhibits a wide range of spot patterns, from none to 22, and is often identifiable by a distinctive “M” or “W” shaped marking behind its head. These consistent patterns within species help entomologists classify and distinguish different types of ladybugs.
Why Ladybugs Have Spots
Ladybugs’ bright colors, including their spots, serve an evolutionary purpose as a warning signal to predators. This phenomenon is known as aposematic coloration, where conspicuous markings advertise that an animal is unpalatable or toxic. Ladybugs produce defensive chemicals called alkaloids, which make them taste bitter or toxic to potential attackers like birds or spiders.
When threatened, ladybugs can release small droplets of a foul-smelling, bitter fluid called hemolymph from their leg joints, a behavior known as “reflex bleeding.” This fluid contains the unpalatable alkaloids, reinforcing the warning conveyed by their bright coloration. Research indicates that brighter colored ladybugs often have higher levels of these toxins, suggesting their vivid appearance is an honest signal of chemical defenses. This deterrent helps ladybugs avoid being eaten, allowing them to survive and reproduce.