The researchers collected samples of different species of leaves and measured their repellency by comparing the contact angles of water droplets of a uniform size deposited on their surfaces by the use of pipettes under laboratory conditions. Experimental Results:

Contrary to the experimental expectations, the results of the experiment did not support the initial hypothesis: some of the leaves collected from the drier environments exhibited greater water repellency than some of the leaves collected from the wettest environments. After analyzing the data, the researchers proposed an alternate evolutionary purpose for the mechanism behind water repellency of different...

According to this hypothesis, the purpose of high water repellency is to promote the efficient draining of rainwater in regions where moisture is scarce, to increase the amount of water available to the roots of their trees. The results naturally suggest repeating similar experiments in conjunction with this alternate hypothesis.