Since the 19th century, plant geographers have been marveling at the luxurious collection of leaf sizes and types that Mother Earth created. Over time, they noticed that plants get longer leaves when they are closer to the equator. On the other hand, these parts of plants tend to shrink when the latitude increases. A new study might hold the answers to what exactly triggers such a phenomenon. The findings suggest that the rich patterns depend on various climatic factors.
The Differences in Leaf Sizes Depend on the Combination of Irradiance, Moisture, and Temperature
Ian Wright of Macquarie University in New South Wales published a new scientific paper in journal Science regarding the leaves of plants across the world. Wright together with his colleagues analyzed a collection of 7,670 species coming from 682 regions of the world.
Their collected data suggested that certain climatic agents dictate the shape of a leaf. The most important agent is the difference between nighttime and daytime leaf-to-air temperatures. As a consequence, the plethora of leaf sizes was created by different mixtures between moisture, irradiance, and temperature.
The various shapes of leaves were created to withstand the risks of chilling and overheating at nighttime and daytime respectively. As a consequence, hot and humid locations are giving birth to plant species with large leaves. On the other hand, the cold and arid climates at high latitudes and elevations are encouraging vegetation to develop short parts.
The Paper Has Also Discovered a New Hint to the Existence of Global Warming
Large leaves come in thicker sizes which develop slower heat exchanges with the air. In other words, they trigger bigger differences in leaf-to-air temperatures. The high temperatures and irradiation make plants to be in higher need for water deposits. Therefore, they create generous leaf sizes.
The paper has also delivered new hints at the impact of global warming on the environment. As the temperatures are getting higher over time, several reports pointed out that the average size of leaves started to increase. This indicates that their environments are getting hotter.
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