Prelims – Biodiversity, species migration, scientific innovations, and climate change impacts.

Mains (GS – I & III) – GS I (Biogeography, species adaptation) | GS III (Biodiversity conservation, climate change, scientific advancements).

Why in News?

A recent study found that painted lady butterflies (Vanessa cardui) don’t have significant genetic differences between short- and long-distance migrants.

• Painted Lady butterfly is a medium-sized butterfly belonging to the Nymphalidae family.
• It is renowned for its extensive migratory patterns and adaptability to various habitats.
• Habitat – Thrives in diverse environments, from temperate grasslands to deserts.
• They can be found on every continent except Antarctica and South America.
• Conservation status – Listed as Least Concern on International Union for Conservation of Nature’s Red List.
• Migratory Behaviour – This species is a long-distance migrant, originating from areas like the desert fringes of North Africa, the Middle East, and Central Asia.
• Each year, it moves northwards, recolonizing mainland Europe and reaching Britain and Ireland.

Key findings of the study

• Isotope Tracking – Scientist studied about the species using the ratios of the isotopes in the wings of species.
• Wings retain hydrogen & strontium isotopes from larval food/water, revealing birthplace.
• No genetic difference in migration – Short- and long-distance painted lady butterflies belong to a single interbreeding population.
• Migration driven by environment – Distance covered depends on environmental factors, not genetics.
• Single migratory cycle – Painted Lady butterfly can travel up to 15,000 km in a single migratory cycle, one of the longest insect migrations on the earth.

A "single migratory cycle" refers an animal (like a bird) makes one round trip between two places—usually moving from a breeding area to a wintering area and back—due to seasonal changes or food needs.

• Multi-generational migration – The full migration cycle spans 8–10 generations.
• Super fly Adaptations – Thoracic muscles like "bodybuilders" enable high-speed, high-altitude flights.
• Wing shape/size doesn’t predict migration distance.
• Different from bird migration – Butterflies don’t return to a single breeding ground, unlike birds.

References

1. The Hindu | Painted Lady
2. Britannica | Painted Lady