Banca de QUALIFICAÇÃO: JOSAFÁ JOSÉ DO CARMO REIS JUNIOR

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOSAFÁ JOSÉ DO CARMO REIS JUNIOR
DATE: 30/08/2022
TIME: 09:00
LOCAL: https://www.meet.google.com/qgw-pywv-hah
TITLE:

Application of geometric morphometrics techniques to understand ecological aspects of marine fish in
northeastern Brazil

KEY WORDS:

geometric morphometrics, demersal fish, trophic ecology, habitat access, fish phenotypic expression, tropical marine habitats.

PAGES: 78
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUMMARY:

The organism's phenotype is the result of the interaction of a set of genetic, ecological, and environmental factors. Functional morphology investigates these phenotypic variations, and geometric morphometrics serves as a tool to quantitatively access the geometric properties of organisms, and contribute to the understanding of ecological phenomena related to morphology. In this work we used body geometric morphometrics techniques on marine fish, to understand ecological aspects linked to trophic ecology and habitat at a community level. Fish were collected along the continental shelf of northeastern Brazil (4-9°S). Individuals were photographed horizontally, and shape was extracted using the techniques of landmarks or outlines along the individuals' bodies. In total we analyzed 120 species distributed in 16 orders and 45 families of demersal fish. The relationship between body shape and trophic ecology indicated that lower trophic levels (herbivores and omnivorous) are characterized by a deep body and longer dorsal and anal fin bases. Top predators showed an elongated body and narrow fins. Using a multiple linear regression, we found that 50% of the variability in trophic level can be explained by morphometric variables, with trophic level increasing with elongation and fish size, the first time such a model has been proposed. Interestingly, intermediate trophic categories (e.g., low predators) showed morphological divergence for a given trophic level. The relationship between body shape and habitat type at first did not indicate clear patterns, when looking at morphospace amplitude and volume. However, when we considered the morphospace formed by the species with the highest abundances in each habitat type (total abundance ≥ 25% and ≥ 50%), we concluded that there is a tendency to find fish with more elongated body shape in the Sand type habitat, when compared to the Algae and SWCR (sand with corals and rocks) habitats. Overall, the 120 species are divided among 13 main fish shape groups, where the rate of body elongation was the main axis of morphological variation found. The morphological characteristics found are directly related to swimming performance, where success in prey capture (e.g., top predators) and habitat access (species adapted to live in open environments with high water flow velocity, e.g., sandy habitats) are favored in species with elongated body shape. Our results can be expanded to other tropical or non-tropical systems, showing that morphometric approaches can provide important insights into the functional characteristics of fish, especially in trophic ecology and habitat use.

BANKING MEMBERS:
Externa à Instituição - BEATRICE PADOVANI FERREIRA - UFPE
Presidente - 2508764 - PAULO JOSE DUARTE NETO
Externa ao Programa - 1619227 - RENATA AKEMI SHINOZAKI MENDES - nullInterna - 1509422 - TATIJANA STOSIC