Name: Mateus Melotti Martins
Type: MSc dissertation
Publication date: 08/06/2020
Advisor:

Name	Role
Rodrigo Giesta Figueiredo	Co-advisor *
Taissa Rodrigues Marques da Silva	Advisor *

Examining board:

Name	Role
Aline Marcele Ghilardi	External Examiner *
Rafaela Velloso Missagia	External Alternate *
Rodrigo Giesta Figueiredo	Co advisor *
Ryan Carlos de Andrades	External Examiner *
Taissa Rodrigues Marques da Silva	Advisor *

Summary: In this work, we propose different ecological scenarios with discussions about predators’
niche partitioning in the Alcântara, Adamantina, and Marília formations, Brazil, and the Kem
Kem Group, Morroco. The trophic relationships between the carnivore archosaurs of these
deposits have been explained mainly by morphological and taphonomical analyses. In order
to test hypotheses about competition among Carcharodontosauridae, Abelisauridae,
Spinosauridae, Anhangueria, Baurusuchidae and Crocodyliformes we used their δ13C and
δ18O isotopic signatures in a mathematical model of linear equations to estimate the
proportion of food resources potentially consumed, and with these data we estimated the
niche breath and overlap among these predators. For all analyzed deposits, the data shows
little niche overlap and competition among predators, demonstrating that most of them
explored food sources differently, corroborating previous inferences. Isotopic analyses
allowed us to make new interpretations on the paleobiology of fossil carnivores, helping to
understand the possible niche partitioning among these highly diverse archosaurs.
Keywords: paleocology, competition, stable isotopes, oxygen, carbon.