Nocturnal Bull Ants Navigate Using Polarised Moonlight

Recent studies have revealed that nocturnal bull ants, specifically Myrmecia pyriformis and Myrmecia midas, utilise polarised moonlight for navigation during foraging. This discovery, made by researchers at Macquarie University in Sydney, marks a unique adaptation in these insects. Unlike many nocturnal animals that rely solely on moonlight, these ants can detect polarised light patterns, aiding their orientation even in dim conditions.

About Polarisation in Light

Light consists of electromagnetic waves. These waves oscillate in various directions. When light travels through the atmosphere, it gets scattered by particles. This scattering causes the light to become polarised, meaning it oscillates in a specific direction. Both sunlight and moonlight can be polarised, but the patterns they create differ . Polarised light provides a stable reference point, which can serve as a natural compass for animals that can detect it.

Ants and Navigation

Prior research established that these bull ants navigate using polarised sunlight. However, as daylight fades, they must adapt to nocturnal conditions. The current study indicates that these ants can detect polarised moonlight throughout the lunar cycle. They adjust their paths based on the e-vector pattern of the light, which changes with the moon’s position. This ability is particularly useful during the waxing and full moon phases when moonlight intensity is higher.

Experimental Findings

Researchers conducted experiments by projecting linearly polarised light onto the ants. They observed how the ants adjusted their paths in response to changes in the light’s e-vector. The study demonstrated that the ants could alter their heading under various moonlight conditions. Notably, during the full moon, the ants displayed the most substantial shifts in direction. Conversely, these shifts decreased during the waning phases, suggesting that the intensity of moonlight influences their navigation.

Significance of Findings

This research is only the second instance of an animal being found to use polarised moonlight for orientation. The first was the dung beetle. The ability of these bull ants to navigate using polarised moonlight opens new avenues for understanding animal navigation. It raises questions about how other species might utilise similar strategies to orient themselves in low-light conditions.

Month: Current Affairs - February, 2025

Category: Science & Technology Current Affairs