Determining factors of flower coloration

Abstract

Diversity and distribution of flower coloration is a puzzling topic that has been extensively studied, with multiple hypotheses being proposed to account for the functions of coloration, such as pollinator attraction, protection against herbivory, and prevention of damage by ultraviolet light. Recent methodologies have allowed studies to consider the visual system of animals other than humans, helping to answer questions regarding the distribution of flower coloration. A survey of keywords in Web of Science shows floral color to be mainly studied in relation to macroevolutionary traits and biochemistry of pigments, focusing on pollination and anthocyanins, respectively. The present paper reviews mechanisms that determine the color of flowers. First, it is discussed how pigment, visual systems and signaling environments influence flower color; secondly, patterns of convergent evolution of flower color is debated, including evolutionary history, pollinator preference, flower color change, flowering season, and habitat. Third and last, patterns of flower coloration that have been found around the globe are addressed. In short, the aim is to contribute to ongoing research, by underlining mechanisms that lead to global patterns of coloration and indicating perspectives for future study on the topic.

Study on the frequency of ultraviolet (UV) light reflectance and absorption in native and nonnative flowering plants

“…Frequency of UV reflection among categories of basic visible petal colors is shown in Figure 1. In arrangement with previously reports findings, yellow and violet flowers exhibited a particularly high probability of reflecting, while white and green flowers generally did not reflect UV [10,11]. Pollination guides usually absorbed UV regardless of their visible color.…”

Reproductive ecology of the prickly pear Opuntia atropes, a native plant subject to management

“…Color variation throughout the floral lifespan could be linked to either the age of the flower per se or to the process of pollination (Erickson & Pessoa 2022), which have both been documented in other Opuntia (Pimienta-Barrios 1990; Piña et al 2007). Our observations indicate that pollination would be a plausible mechanism underlying floral color variation since bagged flowers of the autonomous selfing treatment remained closer to yellow hues (personal observation).…”