Our Research
Although we are interested in every aspect of the reproductive biology of squamate reptiles, we currently have three main lines of investigation.
Reproductive Cycles
We seek to know the timing of various aspects of the reproductive cycles of squamates and which factors influence them
Captive Breeding
We use various reproductive biotechniques and disciplines to assess the reproductive and health status of captive squamates
Evolution of Viviparity
We study morphology, behavior, and ecology of squamates to understand how and why viviparity has evolved in different species
Reproductive Cycles
Brazil has more than 730 species of squamates (lizards, snakes, and amphisbaenians). Still, the reproductive cycles of most of them remain poorly known.
One of our main research interests is to describe the processes and timing of various reproductive aspects of male and female squamates (gametogenesis, mating, sperm storage, ovulation, and egg-laying/birth).
We also want to understand how reproductive traits are affected by biotic and abiotic factors and how reproductive patterns are constrained by phylogeny.
Check out the five most recent publications on this line of investigation.
- Reproductive Strategies of New World Coralsnakes
Almeida-Santos SM, Coeti RZ, Bassi EA.
In: Silva-Jr. NJ, Aird SD. (Org.). The Coralsnakes of Brazil and the Meridional South America. 1ed. Utah: Eagle Mountain Publishing, p. 335-352.
- Reproductive cycles of neotropical boid snakes evaluated by ultrasound
Garcia VC, Almeida-Santos SM.
Zoo Biology
- Sperm storage in coral snakes: A spermatozoa ultrastructural approach
Coeti RZ, Antoniazzi MM, Sánchez R, Almeida-Santos SM.
Zoologischer Anzeiger 290: 49-57.
- Reproduction in the bushmaster (Lachesis muta): Uterine muscular coiling and female sperm storage
de Souza E, Almeida‐Santos SM.
Acta Zoologica.
- Infundibular sperm storage and uterine muscular twisting in the Amazonian lancehead, Bothrops atrox
Silva KMP, Barros VA, Rojas CA, Almeida-Santos SM.
Anatomical Record 303:3145-3154.
Captive Breeding
We often investigate the reproductive biology of squamates by studying free-ranging or museum specimens. However, using this methodology is not always possible, especially when it comes to endangered species (e.g., the golden lancehead, Bothrops insularis) or large-sized species rarely preserved in museums (e.g., anacondas).
In these cases, keeping specimens in captivity is a great alternative to study various reproductive parameters, such as gametogenesis, mating, pregnancy, egg development, and offspring birth.
In the lab, we use various reproductive biotechniques (e.g., ultrasound, radiography, semen collection, and assessment) and disciplines (e.g., parasitology) to assess the reproductive and health status of captive squamates.
Check out the five most recent publications on this line of investigation.
- Short‐term cold storage of seminal samples of the golden lancehead pitviper (Bothrops insularis)
Silva KB, Frediani MH, Angrimani DSR, Coeti, RZ, Pereira RJG, Nichi M, Almeida-Santos SM.
Zoo Biology
- Reproductive cycles of neotropical boid snakes evaluated by ultrasound
Garcia VC, Almeida-Santos SM.
Zoo Biology
- Semen collection and evaluation in Micrurus corallinus
Coeti RZ, Silva KB, Puorto G, Travaglia-Cardoso SR, Almeida‐Santos SM.
Herpetological Conservation and Biology.
- Enterococcus faecalis causes osteitis deformans in a Golden Lancehead snake (Bothrops insularis): a case report
Garcia VC, Navas-Suárez PE, Fonseca-Pinto ACBC, Unruh SM, Knöbl T, Vac MH, Momo C, Lugo MAA, Catão-Dias JL, Almeida-Santos SM.
Braz J Vet Res Anim Sci. 57(4): e163926
- Identification of microchips through diagnostic imaging helps to determine the longevity of the golden lancehead (Bothrops insularis) in captivity
Garcia VC, Unruh S, Almeida-Santos SM. Arquivo Brasileiro de Medicina Veterinaria e Zootecnia, 1: 281-284.
Evolution of Viviparity
Viviparity (live-birth) has evolved at least 150 times in vertebrates. Keeping embryos in the uterus until the end of development imposes several challenges that need to be overcome, including the elimination of metabolic waste, the exchange of respiratory gases, and the transport of water and nutrients.
The evolution of viviparity also has important ecological and behavioral implications. By far, most origins of viviparity (76%) have occurred in snakes and lizards and, which makes them an ideal system for studying the evolution of viviparity.
We have studied the evolution of viviparity in squamates by focusing on morphological and ecological aspects.
Our aim is to understand how and why different species have achieved this evolutionary transition.
Check out the five most recent publications on this line of investigation.
- Evidence of facultative parthenogenesis in three Neotropical pitviper species of the Bothrops atrox group
Cubides-Cubillos SD, Patané JSL, Silva KMP, Almeida-Santos SM, Polydoro DS, Galassi GG, Travaglia Cardoso SR, Silva MJJ.
PeerJ 8: e10097.
- Uterine and eggshell modifications associated with the evolution of viviparity in South American water snakes
Braz HB, Almeida‐Santos SM, Murphy CR, Thompson MB.
Journal of Experimental Zoology Part B 330: 165-180.
- Reproductive modes of the South American water snakes: A study system for the evolution of viviparity in squamate reptiles
Braz HB, Scartozzoni RR, Almeida-Santos SM.
Zoologischer Anzeiger 263: 33–44.