Banca de DEFESA: THIAGO ALMEIDA SANTORO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : THIAGO ALMEIDA SANTORO
DATE: 27/02/2026
TIME: 10:00
LOCAL: Sessão remota
TITLE:

Morphometric Analysis and Extraction Protocol of the Tympanic-Periotic Complex in West Indian Manatees (Trichechus manatus manatus, Linnaeus, 1758).

KEY WORDS:

 morphometrics; tympanic bulla; anatomy; sirenia.

PAGES: 82
BIG AREA: Ciências Biológicas
AREA: Morfologia
SUMMARY:

The West Indian manatee (Trichechus manatus manatus) is an aquatic mammal inhabiting turbid coastal and estuarine environments, where hearing is a primary sense for communication and environmental perception. The tympano-periotic complex (TPC), which houses the middle and inner ear, is the anatomical basis for this capability. Despite its functional importance, the morphology of this structure in T. manatus manatus remains poorly studied due to methodological limitations: the TPC is firmly integrated into the cranial base, making its extraction without damage a significant challenge. The study aimed to develop and validate a novel osteological protocol for TPC extraction while preserving cranial integrity and to conduct the first detailed morphometric analysis of the tympanic bulla in this subspecies. Four skulls (two calves and two adults) from strandings in Rio Grande do Norte, Brazil, were analyzed. The protocol utilizes the "bone window" concept, targeting anatomical fragility points such as sutures and synchondroses, in order to assist its extraction. It involves creating two access points: a "dorsum-lateral window" (via the parieto-squamosal suture) and a "caudal window" (via the supraoccipital-exoccipital synchondrosis), allowing for bilateral intact extraction of the TPC using percussion and grasping instruments. Findings indicate a pattern of functional precocity: linear dimensions of the tympanic bulla are nearly adult-sized at birth. Conversely, there was an increase in total TPC mass post-birth, reflecting continuous pachyostosis and osteosclerosis. The study identified a high degree of bilateral symmetry, crucial for directional underwater hearing, and an absence of significant sexual dimorphism in functional auditory structures. Thus, the study provides a reference method for future morphofunctional, bioacoustic, and evolutionary research, contributing significantly to the conservation of Trichechus manatus manatus.

Keywords: morphometrics; tympanic bulla; anatomy; sirenia.

COMMITTEE MEMBERS:
Presidente - 1672446 - SIMONE ALMEIDA GAVILAN
Interno - 1076490 - FERNANDO VAGNER LOBO LADD
Externa à Instituição - MARIA MORELL