When you think of the tropics, your mind will most likely conjure images of white, sandy beaches, tropical fruit drinks served on the beachside, towering palm trees and colorful wildlife.
Most people, even biologists, thought that tropical fauna and flora are more vibrant and colorful compared to animals and plants found in milder environments and in the poles. For hundreds of years, it seemed no one stood up to contest the theory, until Dr. Rhiannon Dalrymple came along.
Dalrymple is an ecologist from the University of New South Wales in Australia. Her research found that species in the tropics are not more colorful or vibrant compared to species in milder and colder climates.
"On average, we found tropical communities are less colorful than temperate communities", said Dr. Dalrymple. "That is pretty surprising."
Using a spectrometer machine, Dalrymple studied over 500 bird species, over 400 butterfly species, and flowers of over 300 flora species. Apart from measuring the spectrum levels, Dalrymple also measured the ultraviolet (UV) color levels, which are not visible to the naked eye but visible to several animals. The research findings, which is the first of its kind, surprised the scientific community.
Using cross-species analysis, researchers found that species living farther from the equator have greater color diversity. Their colors are distinct and saturated compared to their tropical cousins. The research concluded that species across latitudes share parallel levels of color vibrancy. The scientists believe that this suggests a very strong environmental consistency.
The scientific community did have discussions and even attempted to test the same hypothesis in the last century. They did not, however, have the same technology and techniques.
"They could look at pictures and say whether they felt something was colorful but we didn't have the techniques to quantify coloration", Dalrymple added.
Early explorers' quests for the brightest plant and animal species in the last century probably fueled the popular belief that tropical species are more vibrant. The brighter the colors look, the more expensive the species will sell.
Professor Angela Mole, Dalrymple's co-author and research supervisor, added that there is a bias when it comes to specimen collection. People tend fixate on one bright blue or radiant red butterfly during their walks. It is sad that people rarely notice how the brown butterflies fluttering in the same place because they think the blue and red ones are more vibrant.
