Osiak-Wicha, Cezary, Tomaszewska, Ewa, Muszyński, Siemowit, Flis, Marian, Świetlicki, Michał, and Arciszewski, Marcin B.
Simple Summary: This study aims to investigate the skeletal adaptations of three duck species: the Mallard, Tufted Duck, and Green-Winged Teal. Ducks play a critical role in wetland ecosystems by aiding in seed dispersal and nutrient cycling. To understand how their skeletal structures support different survival strategies and modes of locomotion, this research focuses on the tibiotarsus and humerus bones. Bone samples were collected from deceased ducks, cleaned, and measured for length, weight, and density. Using dual-energy X-ray absorptiometry, bone mineral density (BMD) and content (BMC) were quantified, while mechanical properties such as yield force and stiffness were assessed through a 3-point bending test. The findings demonstrate that each species exhibits unique bone characteristics suited to their specific behaviours and habitats. Mallards, known for their versatility, possess stronger and denser bones, which are advantageous for various environments. They show the highest Seedor index, indicating robust bone structure. Teals, being smaller and capable of rapid flight, have lighter and less dense bones, which are beneficial for quick movements in shallow wetlands but exhibit lower BMD and BMC. Tufted Ducks, which are adapted for deep diving, have bones that are particularly strong and stiff, allowing them to forage effectively underwater. These variations in bone structure and density suggest adaptations to each species' specific ecological strategies and survival mechanisms, reflecting their ecological roles and survival strategies. Understanding these adaptations may provide valuable insights into the functional morphology of ducks. Ducks (Anatinae) play a crucial role in wetland ecosystems, contributing to seed dispersal and nutrient cycling. This study investigates the skeletal adaptations of three duck species: the Mallard (Anas platyrhynchos), Tufted Duck (Aythya fuligula), and Green-Winged Teal (Anas crecca). The focus is on the tibiotarsus and humerus bones to understand how these adaptations support their different locomotion and habitat preferences. Bone samples n = 6 of deceased ducks (both male and female) from each species (for a total of 36 samples) were cleaned and measured for length, weight, and density. Dual-energy X-ray absorptiometry was used to determine bone mineral density (BMD) and bone mineral content (BMC), and mechanical properties like yield force and stiffness were tested using a 3-point bending test. The results show significant differences in body weight, bone weight, and bone length among the species, with Mallards being the largest and Teals the smallest. Male Teals displayed higher relative bone weight (RBW) in their tibia compared to male Mallards, and male Mallards had significantly lower RBW in the humerus compared to the other species. Female Teals had higher RBW than the other species. Teals also exhibited much lower BMD in the tibia, whereas female Mallards had lower BMD in the humerus. The Seedor index revealed that male Mallards had the highest values in the tibia, while female Teals had the lowest. Mechanical testing indicated that Teals had lower yield force and breaking force in the tibia, whereas Mallards showed the highest stiffness in both bones. Tufted Ducks had intermediate values, consistent with their diving behaviour. These findings suggest that the Mallard's robust bones support its adaptability to various environments and diverse locomotion and foraging strategies. The Teal's lighter and less dense bones facilitate rapid flight and agility in shallow wetlands. The Tufted Duck's intermediate bone characteristics reflect its specialization in diving, requiring a balance of strength and flexibility. Understanding these skeletal differences may provide valuable insights into the evolutionary biology and biomechanics of these species, aiding in their conservation and enhancing our knowledge of their roles in wetland ecosystems. By exploring the functional morphology of these ducks, this study aims to shed light on the biomechanical mechanisms that underpin their locomotion and foraging behaviours. [ABSTRACT FROM AUTHOR]