ArticleProceedings of the National Academy of Sciences of the United States of America2022
Skin wrinkles and folds enable asymmetric stretch in the elephant trunk.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 54 citations in OpenAlex.
- The Elephant Trunk Skin Inspires a Highly Sensitive and Deformable, Yet Robust, Armor Skin.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2026Article
- Functional anisotropy of the elephant trunk skin: A biological blueprint for grasping, protection, and tactile sensing.PNAS nexus · 2026Article
- Rotational 3D printing of active-passive filaments and lattices with programmable shape morphing.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Article
- A bionic robotic trunk with tensegrity-enabled elephant-comparable stiffness variability for assisted daily living.Nature communications · 2026Article
- Trunk Tip Wear in Wild African Savanna Elephants.Integrative and comparative biology · 2025Article
- Traversal by Touch: Tactile-Based Robotic Traversal with Artificial Skin in Complex Environments.Sensors (Basel, Switzerland) · 2025Article
- Rapid mimicry of trunk and head movements during play in African Savanna elephants (Loxodonta africana).Scientific reports · 2025Article
- Local postural changes elicit extensive and diverse skin stretch around joints, on the trunk and the face.Journal of the Royal Society, Interface · 2025Article
- Second harmonic generation imaging reveals entanglement of collagen fibers in the elephant trunk skin dermis.Communications biology · 2025Article
- Elephants develop wrinkles through both form and function.Royal Society open science · 2024Article
- Cyclic muscle contractions reinforce the actomyosin motors and mediate the full elongation ofeLife · 2024Article
- Effect of the habitat and tusks on trunk grasping techniques in African savannah elephants.Ecology and evolution · 2024Article
- Maximum trunk tip force assessment related to trunk position and prehensile 'fingers' implication in African savannah elephants.PloS one · 2024Article
- A Year at the Forefront of Hydrostat Motion.Biology open · 2023Review
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Corrections and comments
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Authors and funding
10 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The elephant's trunk is multifunctional: It must be flexible to wrap around vegetation, but tough to knock down trees and resist attack. How can one appendage satisfy both constraints? In this combined experimental and theoretical study, we challenged African elephants to reach far-away objects with only horizontal extensions of their trunk. Surprisingly, the trunk does not extend uniformly, but instead exhibits a dorsal "joint" that stretches 15% more than the corresponding ventral section. Using material testing with the skin of a deceased elephant, we show that the asymmetry is due in part to patterns of the skin. The dorsal skin is folded and 15% more pliable than the wrinkled ventral skin. Skin folds protect the dorsal section and stretch to facilitate downward wrapping, the most common gripping style when picking up items. The elephant's skin is also sufficiently stiff to influence its mechanics: At the joint, the skin requires 13 times more energy to stretch than the corresponding length of muscle. The use of wrinkles and folds to modulate stiffness may provide a valuable concept for both biology and soft robotics.
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