9 Works

Data from: Increased snowfall weakens complementarity of summer water use by different plant functional groups

Yonggang Chi, Lei Zhou, Qingpeng Yang, Shaopeng Li & Shuxia Zheng
Winter snowfall is an important water source for plants during summer in semiarid regions. Snow, rain, soil water, and plant water were sampled for hydrogen and oxygen stable isotopes analyses under control and increased snowfall conditions in the temperate steppe of Inner Mongolia, China. Our study showed that the snowfall contribution to plant water uptake continued throughout the growing season and was detectable even in the late growing season. Snowfall versus rainfall accounted for 30%...

Indirect actuation reduces flight power requirements in Manduca sexta via elastic energy exchange

Jeff Gau, Nick Gravish & Simon Sponberg
In many insects, wing movements are generated indirectly via exoskeletal deformations. Measurements of inertial and aerodynamic power suggest that elastic recovery of energy between wingstrokes might reduce power requirements of flight. We tested three questions. 1) Can the thorax itself provide significant energy return? 2) Does a simple damped elastic model describe the bulk mechanical behavior? and 3) Are different regions of the thorax specialized for elastic energy exchange? We measured deformation mechanics of the...

Data from: How do morphological sharpness measures relate to puncture performance in viperid snake fangs?

Stephanie B. Crofts, Yang Lai, Yuhang Hu & Philip S.L. Anderson
It makes intuitive sense that you need a sharp tool to puncture through a tough material. The typical approach to evaluating sharpness in biological puncturing tools is to treat morphological measurements as a proxy for puncture ability. However there are multiple approaches to measuring sharpness, and the relative influence of morphology on function remains unclear. Our goal is to determine what aspects of tip morphology have the greatest impact on puncture ability, using a) viper...

Data from: Evolution of altruistic cooperation among nascent multicellular organisms

Jordan G. Gulli, Matthew D. Herron & William C. Ratcliff
Cooperation is a classic solution to hostile environments that limit individual survival. In extreme cases this may lead to the evolution of new types of biological individuals (e.g., eusocial super-organisms). We examined the potential for inter-individual cooperation to evolve via experimental evolution, challenging nascent multicellular ‘snowflake yeast’ with an environment in which solitary multicellular clusters experienced low survival. In response, snowflake yeast evolved to form cooperative groups composed of thousands of multicellular clusters that typically...

Data from: Resource addition drives taxonomic divergence and phylogenetic convergence of plant communities

Xian Yang, Guoyong Li, Shao-Peng Li, Qianna Xu, Huanhuan Song, Danyu Sun, Mingxing Zhong, Zhenxing Zhou, Jian Song, Jingyi Ru, Shiqiang Wan & Lin Jiang
1. Anthropogenic environmental changes are known to affect the Earth’s ecosystems. However, how these changes influence assembly trajectories of the impacted communities remains a largely open question. 2. In this study, we investigated the effect of elevated nitrogen (N) deposition and increased precipitation on plant taxonomic and phylogenetic β-diversity in a 9-year field experiment in the temperate semi-arid steppe of Inner Mongolia, China. 3. We found that both N and water addition significantly increased taxonomic...

Autonomous Vehicles and the Ethical Tension Between Occupant and Non-Occupant Safety

Jason Borenstein, Joseph Herkert & Keith W. Miller
Autonomous vehicle manufacturers, people inside an autonomous vehicle (occupants), and people outside the vehicle (non-occupants) are among the distinct stakeholders when addressing ethical issues inherent in systems that include autonomous vehicles. As responses to recent tragic cases illustrate, advocates for autonomous vehicles tend to focus on occupant safety, sometimes to the exclusion of non-occupant safety. Thus, we aim to examine ethical issues associated with non-occupant safety, including pedestrians, bicyclists, motorcyclists, and riders of motorized scooters....

Data from: De novo origins of multicellularity in response to predation

Matthew D. Herron, Joshua M. Borin, Jacob C. Boswell, Jillian Walker, I-Chen Kimberly Chen, Charles A. Knox, Margrethe Boyd, Frank Rosenzweig & William C. Ratcliff
The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by...

Data from: History-dependent perturbation response in limb muscle

Simon Sponberg, Chidinma Chukwueke & Thomas Libby
Muscle mediates movement but movement is typically unsteady and perturbed. Muscle is known to behave non-linearly and with history dependent properties during steady locomotion, but the importance of history dependence in mediating muscles function during perturbations remains less clear. To explore muscle's capacity to mitigate perturbations during locomotion, we constructed a series of perturbations that varied only in kinematic history, keeping instantaneous position, velocity and time from stimulation constant. We find that muscle's perturbation response...

Precise timing is ubiquitous, consistent and coordinated across a comprehensive, spike-resolved flight motor program

Joy Putney, Rachel Conn & Simon Sponberg
Sequences of action potentials, or spikes, carry information in the number of spikes and their timing. Spike timing codes are critical in many sensory systems, but there is now growing evidence that millisecond-scale changes in timing also carry information in motor brain regions, descending decision-making circuits, and individual motor units. Across all the many signals that control a behavior how ubiquitous, consistent, and coordinated are spike timing codes? Assessing these open questions ideally involves recording...

Registration Year

  • 2019
    9

Resource Types

  • Dataset
    8
  • Text
    1

Affiliations

  • Georgia Institute of Technology
    9
  • Henan University
    1
  • University of Montana
    1
  • University of California, San Diego
    1
  • Zhejiang Normal University
    1
  • East China Normal University
    1
  • Chinese Academy of Sciences
    1
  • University of Missouri–St. Louis
    1
  • Emory University
    1
  • University of Illinois at Urbana Champaign
    1