1. School of Biological Sciences, University of Bristol, Bristol, UK
2. Plant Biomechanics Group, Botanic Garden, University of Freiburg, Freiburg im Breisgau, Germany
3. Freiburg Materials Research Center (FMF), University of Freiburg, Freiburg im Breisgau, Germany
4. Department of Biology, California State University Fresno, Fresno, CA, USA