Magnets in their heads: How some animals guide themselves using the Earth's magnetic field

"Alpine newts are born and live as larvae in puddles, ponds and streams. After metamorphosis, while still young, they leave the water and spend almost the entire year in the dense, humid forests of Europe. But when mating season arrives, they return to the same body of water where they were born. To assess their sense of direction, some were taken up to 26 miles (42 km) from their place of birth."

"And they made their way back home in a straight line, without any problems, despite being only 4.7 inches (12 cm) long. Like many other animals, these amphibians can perceive the Earth's magnetic field, which serves as both a compass and a GPS, allowing them to know their location on Earth and find their way back. Humans are only just beginning to understand this superpower known as magnetoreception."

Alpine newts hatch and live as larvae in puddles, ponds and streams, then metamorphose and spend most of the year in dense, humid European forests. During mating season, individuals return to their natal water bodies, sometimes navigating back from distances up to 42 km in straight lines. These amphibians, like many birds, fish, reptiles and some mammals, can detect Earth's magnetic field and use it as both a compass and positional reference. No dedicated magnetoreceptive organ has been definitively identified. Early molecular evidence in bird retinas implicates light-sensitive cryptochrome proteins as part of a complex orientation mechanism.

Read at english.elpais.com