A recent study has revealed that Earth’s seasonal cycles can vary substantially across short distances,even at the same latitudes.
The research team has created a detailed map of seasonal rhythms around the world, which highlights the stark differences in timing for seasonal variations such as the start and end of the growing season. These variations have been found to contribute to high biodiversity in certain ecosystems, lead to the advancement of new species, and even affect the types of coffee harvested in colombia.
According to study co-author Drew Terasaki Hart, an ecologist and data analyst at Commonwealth scientific and Industrial Research Institution (CSIRO) in Australia, “Seasonality may often [be] thoght of as a simple rhythm – winter, spring, summer, fall - but our work shows that nature’s calendar is far more complex.” He further added in a statement that “This is especially true in regions where there are notable differences in shape and timing of local seasonal cycles across landscapes.This can have profound implications for ecology and evolution.”
While the concept of a simple, seasonal growing pattern works well for plants in high latitudes, such as those in Europe and North America, it does not apply to arid or tropical ecosystems. To map vegetation’s growth cycles around the world, Terasaki Hart and his team used 20 years’ worth of satellite data that captured how plants reflected infrared light throughout the year.
They found that areas on the slopes of mountains in tropical regions or with a balmy Mediterranean climate frequently enough exhibit seasonal asynchrony, meaning there are significant differences in thier seasonal cycles across short distances. In these areas, factors such as light and water availability play a more crucial role in determining local plant growth cycles than temperature.
“Our map predicts stark geographic differences in flowering timing and genetic relatedness across a wide variety of plant and animal species,” Terasaki Hart stated. “It even explains the complex geography of coffee harvest seasons in Colombia – where coffee farms separated by just one day’s drive over mountains can have reproductive cycles as out of sync as if they were on opposite hemispheres.”
The study suggests that these starkly different niches over short distances could explain the high biodiversity in tropical regions. As plant and animal species on different seasonal cycles slowly diverge, they may reproduce at different times and eventually form new species after many years.
The findings of this study could also help understand how species evolve in other ecosystems, such as river or ocean environments, and how environments are adapting to climate change. “We suggest exciting future directions for evolutionary biology, climate change ecology, and biodiversity research,” Terasaki Hart added. “But this way of looking at the world has captivating implications even further afield, such as in agricultural sciences or epidemiology.”
Wow, that’s fascinating! I never knew Earth’s seasons could vary so much.