Incredible scientific discovery: they discover that the …

the platypus it is a very special animal. It is poisonous, one of the few mammals to lay eggs, has something like a duckbill, webbed legs, hunts by electro-reception, and wields poisonous spurs capable of causing severe pain in humans. Its unique characteristics make it an important subject of study in the field of evolutionary biology.

Now they have discovered a new property. A study found that the platypus’s fur turns green or cyan under ultraviolet light. This is the first observation of biofluorescence in a mammal that lays eggs, the so-called monotremes. Scientists suggest that this extraordinary trait may not be so rare, and responds to an evolving need to live in the dead of night.

In January of last year, the team of Colorado State University researcher Allison M. Kohler discovered this trait in the flying squirrel’s fur that exhibited varying intensities of pink. So far, fluorescence has only been detected in several species of reptiles, amphibians and even birds, also in marsupial mammals, such as the opossum.

The discovery came by accident while he was doing a nighttime lichen sampling. The team confirmed this peculiarity with specimens of extinct flying squirrels kept in museums. As in the following drawer, the ornitorrincos (Ornithorhynchus anatinus), scientists also set out to examine them.

After analyzing three specimens of the species – a female and a male from the Field Museum of Natural History in Chicago, and another male specimen from the State Museum at the University of Nebraska – the researchers confirmed that their fur shone brightly. verde O cian under the ultraviolet light. It should be noted which is uniformly brown in natural light.

The results, published in the journal Mammalia, show that the platypus’s coat absorbs the UV rays (with wavelengths of 200 to 400 nanometers) and again emits visible light (500 to 600 nanometers), which makes it fluorescent.

Four hypotheses and a debate

The researchers postulated four hypotheses to explain the presence of fluorescence. They are not necessarily exclusive, but are precisely complementary in their function.

Like the marsupial opossum and the placental flying squirrel, the platypus is most active during night. These mammals, and possibly others, may have developed biofluorescence to adapt to low light conditions. The researchers suggest that this way the platypus could see and interact with each other in the darkness.

“What led us to illuminate the museum’s platypus with ultraviolet light was a mixture of chance and curiosity”, explains the main author, Paula Spaeth Anich, Associate Professor of Biology and Natural Resources at Northland College (United States).

The other hypotheses state that this feature was developed to stand out visually, especially in those who inhabit snowy landscapes; it could also serve as an instrument of communication between them and, finally, it is believed that it could play an important role as a tool of defense against predators.

Scientists were also interested in seeing how far the biofluorescent fur trait descended in the mammalian tree. “It is believed that monotremes originated from the marsupial-placental lineage over 150 million years ago. Therefore, it was very curious that these distant relatives [los ornitorrincos] they also had biofluorescent fur, ”the authors note.

The next step will be to collaborate with Australian researchers to observe biofluorescence in wild animals, and thus to deepen the exploration of this phenomenon in the family tree of mammals.