Banca de DEFESA: DIOGO JACKSON DE AQUINO SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : DIOGO JACKSON DE AQUINO SILVA
DATE: 24/02/2025
TIME: 13:00
LOCAL: Videoconferência
TITLE:

Visual communication in fiddler crabs: effects of coloration on sociosexual signaling and predation

KEY WORDS:

color signalling, sexual selection, antipredation, deflection, honest signalling.

PAGES: 173
BIG AREA: Ciências Biológicas
AREA: Zoologia
SUBÁREA: Comportamento Animal
SUMMARY:

Visual communication occurs through signals emitted by a signaller aiming to modify the
receiver's behaviour, providing mutual benefits. For conspecifics, these signals can increase
mating opportunities and prevent unnecessary conflicts but may also attract the attention of
predators. In fiddler crabs, females detect color signals during mate selection, yet the
relationship between these signals and individual or reproductive quality, as well as their role
in mitigating predation costs, remains unclear. This study aimed to investigate the role of
coloration in socio-sexual signalling and prey-predator interactions. We conducted laboratory
analyses using spectrophotometry, photography, and force sensors to extract variables related
to color, shape, and strength. Additionally, field behavioural studies were conducted to assess
competitive ability, attractiveness during mate selection, and effects on predation. Our results
showed that visual signals from claws and carapaces, particularly nuptial coloration, serve as
reliable indicators of individual and reproductive quality. Furthermore, body coloration plays a
critical role in the deflection mechanism, diverting predatory attacks toward non-vital body
regions. We conclude that the visual ecology of fiddler crabs is shaped by distinct evolutionary
pressures, with body coloration playing a crucial role in their adaptation and evolution.

COMMITTEE MEMBERS:
Presidente - 1476621 - DANIEL MARQUES DE ALMEIDA PESSOA
Interno - 1149552 - ARRILTON ARAUJO DE SOUZA
Externo à Instituição - FELIPE MALHEIROS GAWRYSZEWSKI - UnB
Externa à Instituição - TÂNIA MARCIA COSTA - UNESP
Externo à Instituição - VINÍCIUS DE AVELAR SÃO PEDRO - UFSCAR