Can you judge a book by its cover? Predicting skin carotenoids in male guppies Poecilia reticulata using digital image analysis.
2023 (English)Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE credits
Student thesis
Abstract [en]
Carotenoids are life sustaining molecules that appear yellow, red, and orange to the human eye, and animals often use them for sexual signals and as indicators of good health. Males of the Trinidad guppy (Poecilia reticulata) have a conspicuous color pattern that vary greatly in shapes and colors, ranging from black and white to red-orange, yellow, iridescent blues and green. Many studies have investigated the male guppies conspicuous color pattern, but few studies have quantified the pigments biochemically and the strength of the connection between skin coloration and carotenoid concentration is largely unknown. The purpose of this study was to develop a non-invasive method to predict skin carotenoid concentrations using digital photos. Colorimetric analyses were performed to see which color parameter showed the strongest relationship with previously obtained carotenoid measurements from a HPLC analysis. This study also used three different methods that are commonly used for acquiring images to see which method was the most accurate for predicting carotenoid concentrations from the skin of male guppies. The results from the colorimetric analysis showed that images from the video frame capture method was the best at predicting skin carotenoid levels, and although some color parameters significantly predicted skin carotenoid concentration, the predictive power was fairly low and the method would need to be refined in future studies. However, my study suggests that it is indeed possible to use image analysis for predicting skin carotenoid levels of P. reticulata. It provides a non-invasive method that can be used in experiments of sexual selection and mate choice in carotenoid ornamented species such as the guppy P. reticulata.
Place, publisher, year, edition, pages
2023.
Keywords [en]
Carotenoid levels, digital image analysis, Poecilia reticulata, guppy, ornaments
National Category
Other Biological Topics Ecology
Identifiers
URN: urn:nbn:se:lnu:diva-121601OAI: oai:DiVA.org:lnu-121601DiVA, id: diva2:1765187
Educational program
Biology Programme, 180 credits
Supervisors
Examiners
2023-06-122023-06-092023-06-12Bibliographically approved