Post-copulatory sexual selection in a squid (Mollusca: Cephalopoda) with male intrasexual dimorphism and two fertilization sites

• Grant number: 17/16182-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): December 01, 2017
• Effective date (End): November 30, 2021
• Field of knowledge: Biological Sciences - Zoology - Animal Behavior
• Principal Investigator: José Eduardo Amoroso Rodriguez Marian
• Grantee: Lígia Haselmann Apostólico
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Sexual selection influences the reproductive success of each individual and it is not limited to competition for access to the opposite sex. In species in which females copulate with several males during the reproductive period, the paternity dispute can occur even after copulation, through sperm competition and female cryptic choice. Loliginidae squids exhibit complex sexual behaviors and multiple paternity is common in the group. In addition, males of the same species adopt alternative reproductive tactics. Consort males mate in male-parallel position and deposit spermatophores inside the female's mantle cavity, whereas sneaker males mate in head-to-head position and deposit spermatophores in the seminal receptacle. Using the loliginid Doryteuthis plei (Blainville, 1823) as a model species, this project aims to: (i) estimate the number of sneaker males that can potentially contribute to fertilisation of the egg mass, by genotyping spermatozoa naturally stored in the seminal receptacle; (ii) compare the reproductive success of sneaker and consort males through experimental manipulations and paternity analyses; (iii) associate experimental manipulations and paternity analyses with histological analyses of the seminal receptacle of experimental females, aiming at testing previous hypotheses about the existence of seminal plugs in the species; (iv) evaluate the possibility of female cryptic choice through behavioural observations; and (v) investigate the morphology of the copulatory appendage and spermatozoa in order to deepen the characterization of male intrasexual dimorphism in the species. The results of this project will serve as a basis for the understanding of the mechanisms of postcolulatory sexual selection in an animal group that presents two fertilization sites.

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

APOSTOLICO, LIGIA H.; MARIAN, JOSE E. A. R.. Behavior of ``Intermediate{''} Males of the Dimorphic Squid Doryteuthis pleii Supports an Ontogenetic Expression of Alternative Phenotypes. FRONTIERS IN PHYSIOLOGY, v. 10, SEP 13 2019. (17/16182-1)

APOSTOLICO, LIGIA HASELMANN; AMOROSO RODRIGUEZ MARIAN, JOSE EDUARDO. Cephalopod mating systems as models for the study of sexual selection and alternative reproductive tactics: a review. BULLETIN OF MARINE SCIENCE, v. 96, n. 2, p. 24-pg., 2020-04-01. (17/16182-1, 18/19180-2, 13/02653-1, 15/15447-6, 14/11008-5)

APOSTOLICO, LIGIA H.; MARIAN, JOSE E. A. R.. Behavior of "Intermediate" Males of the Dimorphic Squid Doryteuthis pleii Supports an Ontogenetic Expression of Alternative Phenotypes. FRONTIERS IN PHYSIOLOGY, v. 10, p. 10-pg., 2019-09-13. (17/16182-1)

APOSTOLICO, LIGIA HASELMANN; AMOROSO RODRIGUEZ MARIAN, JOSE EDUARDO. Cephalopod mating systems as models for the study of sexual selection and alternative reproductive tactics: a review. BULLETIN OF MARINE SCIENCE, v. 96, n. 2, SI, p. 375-398, APR 2020. (14/11008-5, 15/15447-6, 17/16182-1, 13/02653-1, 18/19180-2)

MARIAN, JOSE E. A. R.; APOSTOLICO, LIGIA H.; CHIAO, CHUAN-CHIN; HANLON, ROGER T.; HIROHASHI, NORITAKA; IWATA, YOKO; MATHER, JENNIFER; SATO, NORIYOSI; SHAW, PAUL W.. Male Alternative Reproductive Tactics and Associated Evolution of Anatomical Characteristics in Loliginid Squid. FRONTIERS IN PHYSIOLOGY, v. 10, OCT 15 2019. (13/02653-1, 18/19180-2, 14/11008-5, 15/15447-6, 17/16182-1)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

APOSTÓLICO, Lígia Haselmann. Post-copulatory sexual selection in a squid (Mollusca: Cephalopoda) with male intrasexual dimorphism and two fertilization sites. 2023. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.