Biology subjects

Franco-Belussi, L.

Publications and source records attributed to Franco-Belussi, L..

3 recordsLinked to original sources

bioRxiv2020

The evolution of red blood cell shape in a continental radiation of fishes

The size and shape of Red Blood Cells (RBC) can provide key information on life history strategies in vertebrates. However, little is known about how RBC shape evolved in response to environmental factors and the role of phylogenetic relationship. Here, we analyzed RBC morphometrics in a continental radiation of fishes testing the hypothesis that phylogenetic relationship determines species occupation of morphospace. We collected blood samples of five specimens of 15 freshwater fish species from six orders and used basic stereological methods to measure cell and nucleus area, perimeter, and diameter, cell and nucleus volume, nucleus:cytoplasm ratio, and shape factor of 50 cells per specimen. Then, we conducted a phylogenetic Principal Components Analysis using a dated phylogeny and built a phylomorphospace. To test if the phylogenetic relationship predicted the phenotypic similarity of species, we calculated multivariate phylogenetic signal. We also estimated the evolution rate of RBC shape for each node and tip using ridge regression. Finally, we tested if the position in the water column influenced RBC shape using a phylogenetic GLS. RBC shape seems to have evolved in a non-stationary way because the distribution pattern of species in the phylomorphospace is independent of the phylogeny. Accordingly, the rate of evolution for shape was highly heterogeneous, with an increase in the genus Pygocentrus. Water column position does not influence RBC shape. In conclusion, RBC shape seem to have evolved in response to multiple selective pressures independent of life history characters.

evolutionary biology↗

bioRxiv2019

Idiosyncratic liver alterations of five frog species to land use changes in the Brazilian Cerrado

Changes in land use trigger environmental changes that can lead to decreased biodiversity and species loss. The liver is an essential detoxification organ that reflects systemic physiological responses to environmental changes. Here, we tested whether land use changes influence the amount of substances from the hepatic cellular catabolism and melanomacrophages of five anuran species in the Brazilian Cerrado. We used routine histological and histochemical techniques. We then use recently developed ecological methods to relate functional traits to environmental variables. There was an increase in the amount of melanin in environments with high proportion of agriculture, as well as variation in the amount of lipofuscin and hemosiderin. Therefore, the area of melanomacrophages in the liver and the metabolic products in their cytoplasm can be used as biomarkers of environmental changes in regions with intense agricultural activities. Our results add a new perspective to the influence of land use changes on environmental health by highlighting the effect of environmental changes on internal morphological aspects of animals.View Full Text

zoology↗

bioRxiv2017

Environmental correlates of internal coloration in anurans vary throughout space and lineages

Internal organs of ectotherms have melanin-containing cells. Several studies analyzed their developmental origin, role in immunity, and hormonal regulation. However, little is known about how environmental variables influence the distribution and quantity of organ coloration. Here, we addressed how environmental variables (temperature, UV, and photoperiod) influence the internal coloration of amphibians after controlling for spatial and phylogenetic autocorrelations. Coloration in all organs was correlated with phylogeny. However, the coloration of the heart, kidneys, and rectum of hylids, R. schneideri, some Leptodactylus, and Proceratophrys were influenced by temperature and photoperiod, whereas that of the testicle, lumbar parietal peritoneum, lungs, and mesenterium of Leiuperinae, Hylodidae, Adenomera, most Leptodactylus were influenced by UVB and temperature variation. Therefore, the amount of internal melanin seems to be a key trait influencing species distribution of frogs throughout space, since it can protect internal organs against the deleterious effect of high UV-B, temperature variation, and photoperiod.\n\nSignificanceThe functions of internal coloration in fishes and frogs are little known. Internal pigmentation is commonly altered in fish and the degree of response is correlated with body transparency levels, suggesting possible adaptive functions. Here, we assume that internal melanin has protective functions against UV-B, temperature variation, and photoperiod. Thus it could influence frogs species distribution throughout space. The melanin coloration of each organ was influenced by distinct environmental variables depending on the lineages of species. Our results could direct further studies about the functions of internal coloration.

evolutionary biology↗