Biology subjects

Schulz, A. K.

Publications and source records attributed to Schulz, A. K..

4 recordsLinked to original sources

bioRxiv2025

Scaly-Tail Organ Enhances Static Stability during Pel's Scaly-tailed Flying Squirrels' Arboreal Locomotion

Scaly-tailed squirrels (Anomaluridae) are one of the least studied mammalian families. Their namesake is due to a peculiar and unique scaly-tail organ extruding from the caudal vertebrate that has been predicted to help reduce skidding. This study investigates the function of the scaly-tail organ found in Anomalurus pelii, investigating its potential role in enhancing arboreal locomotion. As these animals glide from tree to tree in a habitat abundant with smooth-bark trees, we hypothesize that the scaly-tail organ assists with friction enhancement in their native smooth-bark habitat. Through a combination of analyses using mathematical and physical models for experimental validation, we explore whether the scaly-tail organ could improve the sliding and overturning stability during perching. Our experimental results showed that the scaly-tail organ can act as a skid-reduction mechanism by enhancing substrate engagement on intermediate roughness substrates by 58%. Mathematical models showed the scaly-tail organ enhances overturning stability by acting as an additional support point. Our model showed that the scaly-tailed squirrel can reach up to 82.5{whitebullet} inclination without claw force; however, without scales, it reduces to 79.6{whitebullet}. Overall, this research highlights the functional significance of scaly-tail organs in adaptations in scaly-tailed flying squirrels and contributes to our understanding of their locomotion strategies and environmental stresses. Our study also provides insights into innovative perching mechanisms for robots operating in arboreal environments.

bioengineering↗

bioRxiv2023

Elephants develop wrinkles through both form & function

The trunks of elephants have prominent wrinkles from their base to the very tip. But neither the obvious differences in wrinkles between elephant species nor their development have been studied before. Asian elephants have more dorsal major, meaning deep and wide, trunk wrinkles (~126 {+/-} 25 SD) than African elephants (~83 {+/-} 13 SD). Both species have more dorsal than ventral major trunk wrinkles and a closer wrinkle spacing distally than proximally. In Asian elephants wrinkle density is high in the trunk wrapping zone. Wrinkle numbers on the left and right sides of the distal trunk differed as a function of trunk lateralization, with frequent bending in one direction causing wrinkle formation. MicroCT-imaging and microscopy of newborn elephants trunks revealed a constant thickness of the putative epidermis, whereas the putative dermis shrinks in the wrinkle troughs. During fetal development wrinkle numbers double every 20 days in an early exponential phase. Later wrinkles are added slowly, but at a faster rate in Asian than African elephants. We characterize the lifelong development of trunk wrinkles in Asian and African elephants and discuss the relation of species differences in trunk wrinkle distribution and number with behavioral, environmental, genetic, and biomechanical factors.

physiology↗

bioRxiv2023

Intradisciplinary Growth of Sustainability-Minded Engineers through Conservation Technology

BackgroundThe need for sustainability-minded engineers prepared to address complex societal challenges has grown exponentially in recent years. Frameworks like the United Nations (UN) Sustainable Development Goals (SDGs) have begun to drive structural changes in engineering education, including new ABET accreditation focused on sustainability. The new field of conservation technology allows engineers to develop sustainability competencies and identities as conservationists and environmentalists. PurposeThis manuscript describes an assessment of student identity development in conservation and environmentalism in the GaTech4Wildlife Vertically Integrated Project (VIP) course at Georgia Tech. The course uses the principles of Human-Centered Design along with the UN Sustainable Development Goals and project-based learning to solve conservation-oriented, real-world problems and develop sustainability-minded engineers. Design/MethodUndergraduate students participated in the course and utilizing both in-person interviews and post-course assessment, students were assessed for course themes and identities. The sample consisted of students from the College of Engineering and the College of Computing. ResultsSince 2019, over 50 students have participated in this Tech4Wildlife course. Based on surveys and interviews of nearly 20 of the most recent students, students transitioned from identifying as engineers and coders with no sustainability knowledge to nearly doubling their identity measures as conservationists and environmentalists after only one semester. ConclusionsTo teach the next generation of sustainability-minded engineers, interdisciplinary, project-based courses grounded in Sustainable Development Goals may offer a meaningful pathway for students to develop both technical skills and conservationist identities.

scientific communication and education↗

bioRxiv2022

Elephants have an adaptable prehensile grip

Elephants have long been observed to grip objects with their trunk, but little is known about how they adjust their strategy for different weights. In this study, we challenge a female African elephant at Zoo Atlanta to lift 20 to 60 kg barbell weights with only its trunk. We measure the trunks shape and wrinkle geometry from a frozen elephant trunk at the Smithsonian. We observe several strategies employed to accommodate heavier weights, including accelerating less, orienting the trunk more vertically, and wrapping the barbell with a greater trunk length. Mathematical models show that increasing barbell weights are associated with constant trunk tensile force and an increasing barbell-wrapping surface area due to the trunks wrinkles. Our findings may inspire the design of more adaptable soft robotic grippers that can improve grip using surface morphology such as wrinkles.

bioengineering↗