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Punxatawney Phil, the main character of the annual winter parade known as Groundhog Day, isn’t very good at his job. Their predictions are often more wrong than correct.
On Friday, the seer did not see the marmot’s shadow, indicating that spring had come early. However, technically, winter will end on the spring equinox, which falls on the evening of March 19.
But the groundhog is just one of many animals that, according to folklore, have an uncanny ability to predict the weather; these include cows said to lie down before an early rain, and woolly bear caterpillars purportedly decked out in less color ahead of a cold winter. .
Many of these associations are disconnected from modern science; but among the myths there are occasionally hints of documented facts.
Phenology is the study of how seasonal events in the lives of plants and animals change with weather and climate, such as how fish or migratory birds respond to water and air temperature. (As information, this field of study can be practiced as a hard science and is completely different from the pseudoscientific “phrenology.”)
The U.S. National Phenology Network tracks when ecological markers of spring arrive in the United States, and the season is already in bloom in certain places along the east and west coasts.
Theresa Crimmins, director of the U.S. National Phenology Network, said that although the Punxatawney Phil does not make a reliable prediction of the arrival of spring, phenology offers scientific support for other seemingly superstitious axioms about the natural world.
“Humans have been observing (environmental conditions) for thousands of years, that is, as long as humans have existed,” Crimmins said. “So (many of these proverbs) actually work because they kind of capture the relationships between environmental conditions and plant response.”
But while folklore often assumes that animal behavior foreshadows future weather events, in reality flora and fauna respond to weather and climate.
Plants and their predictions
Groundhog Day has its roots in traditions probably imported to the United States from Germany, where the animal that predicted winter was a badger rather than a groundhog.
However, many tried-and-true proverbs about the natural world come from Native American communities.
“Planting corn when oak leaves are the size of squirrel ears is an example,” says a University of Wisconsin-Madison paper on phenology. “You know that planting corn has nothing to do with oak leaves or squirrels. “However, Native Americans had made the observation centuries ago that the soil was warm enough to prevent the seeds from rotting, but if corn was planted at this time it was still early enough to produce a favorable harvest.”
Crimmins points out that there are many other predictors of upcoming ecological events expressed in the leaves, fruits and flowers of plants.
For example, the shade blow serviceberry is a small tree native to parts of eastern North America, and its name is believed to come from the fact that it bears flowers at the same time of year when shad begin their river migration. The Lenape and other Native American populations recognized this long ago and prepared to fish when the plant began to bloom.
Animals and severe weather conditions
The Old Farmer’s Almanac compiled several dozen proverbs about insects, animals, and their ability to predict the weather.
Some of the claims are questionable. Grass-eating dogs, for example, are much less accurate in predicting rain than a meteorologist’s weather report.
But there is research to suggest that some animals may have an innate sense that helps them detect when a disaster is approaching.
For example, golden-winged warblers evacuated an area of Tennessee more than 24 hours before a devastating string of tornadoes hit the region, according to a December 2014 study published in the journal Current Biology.
The study authors speculated that migratory birds were listening for infrasound (sound at frequencies too low for humans to hear) associated with storms and took this as a warning sign.
Researchers in Germany also investigated whether various animal species could detect an approaching earthquake. Scientists found that animals, which collectively included cows, sheep and dogs, exhibited increased activity up to 20 hours before the earthquake, according to a report by the Max Planck Society in Germany, a nonprofit association of research institutes.
Insects and frogs
The idea that crickets can act as nature’s thermometer is also true. Insects are ectotherms, meaning their body temperature varies with the temperature of the surrounding environment, and they routinely chirp faster in warm weather.
According to Dolbear’s Law, a formula that explains this relationship between crickets and weather, the National Oceanic and Atmospheric Administration notes, “You can count the number of chirps in 15 seconds, add 40, and that will give you the temperature in Fahrenheit.”
Frogs also make unique calls when it’s about to rain.
Professor emeritus of environmental studies, Dr. Gordon Miller said: “Many twentieth-century herpetologists have confirmed and clarified the traditional observation that various frog species sometimes make a distinctive sound ‘rain call’ shortly before rainy weather.” via email at Seattle University.
Miller said the calls were “perhaps triggered by increased humidity prior to precipitation.”
Fact and folklore
But other metaphors about animals’ ability to predict seasonal conditions are false.
The woolly bear, a type of caterpillar also called the woolly worm, is thought to predict the severity of the upcoming winter with its colorful bands. More black on the beetle supposedly indicates harsher conditions on the road.
But in reality, “the color of caterpillars depends on how long the caterpillar has been feeding, its age, and its species,” according to the National Weather Service. “The better the growing season, the more it will grow. This causes narrower red-orange bands to form in the middle. Therefore, the width of the banding is an indicator of the growth of the current or past season rather than an indicator of the severity of the coming winter.”
Climate change and phenology
Crimmins emphasized that unusual animal behavior could also be a response to a changing climate. And often not in a good way.
Crimmins stated that the climate crisis and human development are causing all kinds of ecological problems. For example, bears enter hibernation later and wake up earlier due to warmer weather. This could lead to more human-bear interactions as bears search for food, and there are concerns about how shorter hibernation periods affect bear pregnancies.
Miller added: While frogs can predict future rainfall, “as many amphibian species continue to decline due to a variety of environmental and climatic factors, perhaps their clearest call to us today, as Rachel Carson noted of birds in 1962, is this: their diminishing chorus.” and their growing silence.
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