Live birth has evolved many times independently in vertebrates, such as mammals and diverse groups of lizards and snakes. However, live birth is unknown in the major clade Archosauromorpha, a group that first evolved some 260 million years ago and is represented today by birds and crocodilians. Here we report the discovery of a pregnant long-necked marine reptile (Dinocephalosaurus) from the Middle Triassic (∼245 million years ago) of southwest China showing live birth in archosauromorphs. Our discovery pushes back evidence of reproductive biology in the clade by roughly 50 million years, and shows that there is no fundamental reason that archosauromorphs could not achieve live birth. Our phylogenetic models indicate that Dinocephalosaurus determined the sex of their offspring by sex chromosomes rather than by environmental temperature like crocodilians. Our results provide crucial evidence for genotypic sex determination facilitating land-water transitions in amniotes.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5316873 | PMC |
http://dx.doi.org/10.1038/ncomms14445 | DOI Listing |
JAMA Netw Open
January 2025
Center of Data and Knowledge Integration for Health, Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Bahia, Brazil.
Importance: Congenital Zika syndrome (CZS) can lead to a range of developmental and neurological issues, which increases the risk of early death. However, the all-cause and cause-specific mortality in children with CZS in the first 5 years of life remain unknown.
Objective: To compare the hazard of all-cause and cause-specific mortality before age 5 years among children with and without CZS in Brazil.
Fertil Steril
January 2025
Department of Obstetrics, Gynecology and Women's Health, Albert Einstein College of Medicine, Montefiore's Institute for Reproductive Medicine and Health, Hartsdale, New York.
Hum Reprod
January 2025
HealthPlus Fertility Center, HealthPlus Network of Specialty Centers, Abu Dhabi, United Arab Emirates.
BMC Pregnancy Childbirth
January 2025
Regional Institute for Population Studies, University of Ghana, Legon-Accra, Ghana.
Background: The prevalence of adolescent pregnancy is high in developing countries and poses a public health threat. This study aimed to assess the coverage and correlates of optimal ANC visits, early initiation of ANC visits, assisted delivery and health facility delivery among adolescent mothers.
Methods: We analysed data from the 2017 Ghana Maternal Health Survey (GMHS), using a sample of 567 (weighted) and 527 (unweighted) adolescent mothers with at least one live birth or stillbirth in the five (5) years preceding the survey.
BMJ Open
January 2025
Leicestershire Partnership NHS Trust, Leicester, UK.
Objective: Explore the nature and prevalence of long-term conditions in individuals with intellectual disability.
Design: Retrospective longitudinal population-based study.
Setting: Primary and secondary care data across the population of Wales with the Secure Anonymised Information Linkage (SAIL) Databank.
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