Article
Multidisciplinary Sciences
Ashley R. Reynolds, Kevin L. Seymour, David C. Evans
Summary: This study describes a fossil assemblage of saber-toothed cats from Pleistocene coastal deposits in Ecuador, indicating a catastrophic mass mortality event involving at least one adult and two subadults. The fossil record shows familial relatedness between the subadults and the adult, suggesting prolonged parental care in Smilodon fatalis during their juvenile years.
Article
Multidisciplinary Sciences
Mairin A. Balisi, Abhinav K. Sharma, Carrie M. Howard, Christopher A. Shaw, Robert Klapper, Emily L. Lindsey
Summary: Reconstructing the behavior of extinct species can be challenging, especially when they have no living analogues. This study analyzed a saber-toothed cat fossil using CT imaging, revealing it suffered from hip dysplasia and likely relied on a social group for feeding and protection. These findings suggest a range of social strategies in Smilodon.
SCIENTIFIC REPORTS
(2021)
Article
Entomology
Qihang Li, Longyan Chen, Meike Liu, Wenkai Wang, Simone Sabatelli, Andrea Di Giulio, Paolo Audisio
Summary: This study utilized SEM to observe and study the fine morphology of sensilla on the antennae and mouthparts of the pollen-beetle Meligethes (Odonthogethes) chinensis, revealing multiple types and subtypes of sensilla. By comparing similar sensilla in other insects, the research aimed to discuss the evolution and functions of these sensorial structures in specialized flower-inhabiting insects.
Article
Evolutionary Biology
Lucy C. Huntley, David J. Gower, Filipa L. Sampaio, Ellen S. Collins, Anjali Goswami, Anne-Claire Fabre
Summary: The Uropeltidae, a family of small, fossorial snakes endemic to south Asia, are known for their highly modified head and tail morphology. Research on intraspecific variation in morphology and tail function is lacking due to their secretive nature. This study on Rhinophis philippinus specimens found slight differences in cranial and tail-shield shape, with significant sexual dimorphism only in certain scale numbers and tail length. Functional constraints due to head-first burrowing likely led to strong stabilizing selection in head and cranial shape, with common tail function related to predator avoidance and defense.
JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH
(2021)
Article
Biotechnology & Applied Microbiology
Song Guo, Shuyun Huang, Xi Jiang, Haiyang Hu, Dingding Han, Carlos S. Moreno, Genevieve L. Fairbrother, David A. Hughes, Mark Stoneking, Philipp Khaitovich
Summary: The study revealed that miRNA expression in human placental samples is influenced by population affiliation and fetal sex, with male-associated miRNA differences leading to the inhibition of target gene expression in specific functional pathways. Population-driven miRNA differences may represent neutral changes with minimal functional impacts.
Article
Multidisciplinary Sciences
Hugo Schmokel, Aisling Farrell, Mairin F. Balisi
Summary: The study found a high prevalence of skeletal disease in Ice Age predators, specifically the saber-toothed cat and dire wolf. Contrary to predictions, subchondral defects resembling osteochondrosis dissecans (OCD) were found in the shoulder and stifle joints of these extinct predators. The high prevalence may indicate inbreeding as the animals approached extinction.
Article
Agriculture, Dairy & Animal Science
Jane Costa, Lucas Torres, Leticia Paschoaletto, Ana Luiza Anes Pimenta, Hugo A. Benitez, Manuel J. Suazo, Carolina Reigada, Helcio R. Gil-Santana
Summary: This study provides new insights into the sexual dimorphism of the first instar nymphs of the giant stick insect Cladomorphus phyllinus, revealing rare characteristics and highlighting the importance of further research on its biology and ecology.
Article
Biochemistry & Molecular Biology
Jeanne Tonnabel, Etienne K. Klein, Ophelie Ronce, Sylvie Oddou-Muratorio, Francois Rousset, Isabelle Olivieri, Alexandre Courtiol, Agnes Mignot
Summary: The study investigates sexual dimorphism in plants, specifically in the dioecious wind-pollinated shrub Leucadendron rubrum, and suggests that sexual differences exist in selection of traits and effective fecundity. While males exhibit stronger spatial autocorrelation in effective fecundity at a smaller scale, higher plant density is associated with lower effective fecundity in males but not in females. Despite these sex-specific sensitivities to environmental heterogeneity, directional selection for certain traits is observed in both sexes without sexually antagonistic selection on strongly dimorphic traits.
Article
Genetics & Heredity
April L. Peterson, Bret A. Payseur
Summary: The study found that genetic variation in recombination rates differs between males and females in house mice. Male genome-wide recombination rates vary significantly among strains, while female recombination rates in the same strains are more stable. Additionally, high recombination rates in males are associated with stronger CO interference and more double-strand breaks.
Article
Environmental Sciences
Khor Waiho, Mhd Ikhwanuddin, Muyassar H. Abualreesh, Alexander Chong Shu-Chien, Sairatul Dahlianis Ishak, Mohamad Jalilah, Ghazali Azmie, Hanafiah Fazhan
Summary: Sexual dimorphism is generally obvious in brachyurans, with differences between species being more pronounced than those between sexes within the same species. Reproduction-related characteristics exhibit similar sexual differences across species. Regional intraspecific divergence is observed in mud crab species from certain areas.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Ecology
Lydia K. Koutrouditsou, Robert L. Nudds
Summary: The European swallowtail butterfly is named for its long and narrow prominences extending from the trailing edge of the hindwings, but the exact function of these tails remains unclear, with potential roles in predator avoidance and aerodynamic performance. Sexual dimorphism in size is observed in the swallowtail, but whether the tail length also shows dimorphism is unknown. Research suggests that tail morphology may be primarily determined by factors associated with predator avoidance, rather than solely driven by aerodynamics.
ECOLOGY AND EVOLUTION
(2021)
Article
Multidisciplinary Sciences
Caihong Han, Qionglin Peng, Mengshi Sun, Xinyu Jiang, Xiangbin Su, Jiangtao Chen, Mingze Ma, Huan Zhu, Xiaoxiao Ji, Yufeng Pan
Summary: Most animal species exhibit dimorphic sexual behaviors, with males showing higher levels of aggression. Current models have focused on the male-specific product of the fruitless gene, fruM, which controls male courtship and male-specific aggression patterns in fruit flies and describes a male-specific mechanism underlying sexually dimorphic behaviors. This study demonstrates that the doublesex gene (dsx), which produces male-specific DsxM and female-specific DsxF transcription factors, also plays a role in the nervous system to control both male and female sexual and aggressive behaviors.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Biochemistry & Molecular Biology
Pamela C. Lovejoy, Kate E. Foley, Melissa M. Conti, Samantha M. Meadows, Christopher Bishop, Anthony C. Fiumera
Summary: Toxicant resistance is a complex trait influenced by genetics and environment, with sexual dimorphism and significant interactions between sexes in susceptibility genes. Despite a positive correlation, differences in susceptibility and gene associations between males and females highlight the importance of considering both sexes in toxicant susceptibility studies.
Article
Multidisciplinary Sciences
Bartosz Borczyk
Summary: Sea kraits exhibit clear sexual dimorphism in skull form that may be explained by intersexual differences in feeding habits and reproductive roles. Males and females follow distinct allometric trajectories in skull shape and size, corresponding to dietary divergence between the sexes.
Article
Biology
Zackary A. Graham
Summary: Humans are fascinated by exaggerated morphological structures, like elk antlers and peacock trains, but the cost to develop and use these traits in the environment can select for specific sizes or shapes. In aquatic environments, exaggerated structures are less common due to selection to reduce drag, but some crayfish species possess exaggerated claw gaps. The function of these gaps, such as aiding in movement against currents, was tested in the New River crayfish, highlighting a unique adaptation in aquatic environments.