Nature has its own rhythm. Flowers bloom, bees arrive, fruits grow, and then life moves on. But with the changing climate, this rhythm is now being disrupted. Clearly, the impact of climate change is no longer limited to temperatures or melting glaciers. Its effects are also clearly visible on the plants and flowers in the most biodiverse regions of the Earth.
A new study on this matter has revealed that with the warming of the earth, the flowering time in tropical areas has started changing.
Many tropical plants are now blooming weeks, even months, earlier or later than they used to. Nature’s clock is shifting. This change is very slow and is invisible to the naked eye. Howevre, its effects are profound enough to disrupt entire ecosystems.
This study has been done by scientists Skyler Graves and Erin Manjito-Tripp associated with the University of Colorado Boulder, USA, the results of which have been published in the journal PLOS One.
For their study, the scientists examined more than 8,000 flower specimens collected between 1794 and 2024. These specimens were preserved in museums and herbaria. The scientists selected a total of 33 tropical species.
The analysis revealed that, on average, the flowering time of flowers is shifting by about two days per decade. This change may seem small at first glance, but over 100 to 200 years, this change adds up to several weeks.
Some examples are even more surprising: Ghana’s rattlepod shrubs have shifted their flowering time by about 17 days between 1950 and 1990. Meanwhile, Brazilian amaranth trees are now blooming about 80 days later than they did in the 1950s.
These changes are not minor. They are so significant that they could disrupt the balance between plants and the organisms that depend on them. Flowering marks the moment when pollination begins, fruiting sets in, and the food cycle of birds and animals continues.
But if a plant flowers when pollinating insects are not present, seeds will not be formed. Fruits will be scarce. This will affect the birds and animals that depend on those fruits. As a result, the balance that has existed for years could be disrupted.
In tropical regions, the relationships between plants, insects, and animals are unique and delicate. So even slight changes in timing can affect the entire food web.
In tropical regions, temperatures remain relatively constant throughout the year, so it was previously believed that climate change would not significantly affect flowering time there. But this study disproves this assumption.
The study confirmed that the rate of change is similar to that observed in temperate and cold regions, meaning tropical plants are equally sensitive to climate change.
Another significant aspect of this research is that the scientists used centuries-old herbarium records. A single flower preserved in 1820 is not just a specimen, but evidence of the climate and ecology of that time. Digital technologies now allow these records to be analysed on a large scale. This could provide answers to many questions related to climate, diseases, invasive species, and biodiversity.
Some recent research has observed similar changes in India. Several studies on trees have revealed evidence that climate change is having a profound impact on trees. A similar phenomenon was observed in December 2022, when mango trees in Telangana and Odisha began blooming as early as the third week of December, at least a month earlier than usual.
Experts had held unseasonal rains and warmer than normal winters responsible for this.
Similarly, another study published in the journal Ecology Environment and Conservation in March 2016 found that climate change is causing mango trees to blossom earlier and later. Another study found that rising temperatures in the Hindu Kush Himalaya region have led to a 38 per cent decline in pine trees. The Hindu Kush Himalaya is warming much faster than the global average.
One such research has shown that with increasing temperature, the trees present on the mountains are now shifting towards higher altitudes, meaning that the mountain tree line is now shifting towards higher altitudes.
Tropical regions are among the world’s most biodiverse regions, yet they have received relatively little research. The widespread changes in flowering times are a warning sign for conservation efforts.
The message is clear: change has already begun in the forests, and this change will not be limited to flowers alone. Therefore, it is crucial to understand and manage this changing rhythm of nature.