How Does Math Relate to the Life Cycle of Periodical Cicadas?

November 25, 2024

Two broods of periodical cicadas have emerged together for the first time in over 200 years. Brood XIX appears in the southeastern U.S., while Brood XIII is found in the Midwest. Additionally, Australian greengrocer cicadas, which follow a seven-year cycle, have also emerged, and overlap has taken 1,547 years to align.

Life Cycles of Cicadas

Cicadas spend most of their lives underground and emerge every 13 or 17 years to eat, reproduce, and die. These life cycles are based on prime numbers. This strategy helps them avoid predators.

The Role of Prime Numbers

Prime numbers reduce overlap with predators. Predators often have life cycles of 2, 3, 4, 5, 6, or 7 years. Cicadas with a 12-year cycle face frequent encounters with these predators. Conversely, those with a 13-year cycle only overlap with a 2-year predator every 26 years.

Mathematical Concepts

The concept of the lowest common multiple explains cicada survival. Prime-numbered cycles help avoid predator overlap. This mathematical principle illustrates the connection between biology and math.

Prime-numbered cycles may also prevent interbreeding between different cicada broods. This ensures genetic diversity and the survival of distinct groups.

Australian and American Cicadas

Australian cicadas follow a 7-year cycle. Their emergence rarely overlaps with American cicadas. The lowest common multiple of 7, 13, and 17 is 1,547 years, explaining the infrequency of their alignment.

Mathematics appears in various biological contexts. For example, gears in machines often have a prime number of teeth. This design minimises wear and tear.

Historical Context

The last simultaneous emergence of American and Australian cicadas occurred in 477 AD. This coincided with the decline of the Western Roman Empire. Their reappearance now adds an intriguing layer to current global uncertainties.

Important Facts for Exams:
Brood XIX – Brood XIX is a group of periodical cicadas emerging in the southeastern United States. This brood appears every 13 or 17 years, contributing to unique ecological phenomena.
Lowest Common Multiple – The lowest common multiple is a mathematical concept that determines the smallest multiple shared by two or more numbers. It explains the cicadas’ rare alignments and predator avoidance strategies.
Greengrocer Cicadas – Greengrocer cicadas are Australian insects following a seven-year life cycle. Their emergence rarely coincides with American cicadas, denoting the significance of prime-numbered cycles in survival.
Interbreeding Prevention – Prime-numbered life cycles in cicadas may prevent interbreeding between different broods. This genetic strategy ensures diversity and enhances the resilience of cicada populations.

« Previous Post Next Post »