Lisu
Plantae
EOL Text
Structure and shape provide flexibility: vines
Architecture of vines increases flexibility via soft tissue components and ribbon-like shape.
"There is another way in which the stem anatomy of woody vines differs from that of trees. In trees, the wood or xylem, of which only the newest and outermost annual ring actually conducts water, is in the form of a solid cylinder whose rigidity is able to support large crowns of leaves and branches. Vines need to be more flexible to cope with the twists and turns of climbing or the stresses that result when they partly or completely slip away from their supports. Woody vines achieve flexibility by having a considerable amount of soft tissue as well as wood in their stems. In some, the cylinder of wood is divided into segments that alternate with soft tissue; in others, there are alternating cylinders of wood and soft tissue. Some woody vines also have flattened, ribbon-like stems to achieve greater flexibility." (Dawson and Lucas 2005:17)
Learn more about this functional adaptation.
- Dawson, J.; Lucas, R. 2005. The Nature of Plants: Habitats, Challenges, and Adaptations. Portland: Timber Press. 314 p.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/0072d3a90e81a19c55627a4cc19774aa |
Flexibility limits bending in wind: trees
The trunks of trees reduce their tendency to bend in the wind due to their torsional flexibility.
"Another use of torsional flexibility, perhaps less sophisticated, happens on a larger scale. Wind on a tree will twist it unless everything (including the wind) is perfectly symmetrical about the trunk. But twisting brings bits of tree closer to a downwind orientation and brings the bits into closer proximity to each other. Both should reduce the tendency of the tree to bend over. Clever--lowering torsional stiffness ought to reduce the requirement for flexural stiffness! While we don't have data for any intact tree, the effect has been shown for clusters of leaves (Vogel 1989), and casual observations in storms suggest that it works on larger scales. Tree-level use is consistent with the relatively low values of torsional stiffness of fresh samples of tree trunks and bamboo culms (Vogel 1995b)." (Vogel 2003:382)
Learn more about this functional adaptation.
- Steven Vogel. 2003. Comparative Biomechanics: Life's Physical World. Princeton: Princeton University Press. 580 p.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/8cd0058a113581f19d0812fe6c789509 |
Vessels resist bubble formation: trees
Xylem vessels running up tree trunks prevent gas bubble formation because all surfaces are hydrophilic.
"The water columns in the xylem vessels running up the trunk of a tree provide a dramatic example of what's possible when all surfaces are hydrophilic. With megapascals of negative pressures virtually any dissolved gas ensures supersaturation, yet bubbles rarely form. It's a good thing, too- a tiny bubble would rupture a water column since any bubble is itself an appropriate surface for gas formation; and, once formed, bubbles grow almost explosively in a supersaturated liquid." (Vogel 2003:111)
Learn more about this functional adaptation.
- Steven Vogel. 2003. Comparative Biomechanics: Life's Physical World. Princeton: Princeton University Press. 580 p.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/24d6a9e67488edea64d1a7c0b5edede5 |
Plants survive few pollinators: peatland plants
Plants in peatlands survive low numbers of pollinators by staggering their flowering times.
"Many plant species depend on insect pollinators, and such insects are often rare on peatlands. Bog dwarf shrubs have separated flowering times. For instance, in Ontario the flowering sequence is Chamaedaphne calyculata, Andromeda glaucophylla, Kalmia polifolia, Rhododendron groenlandicum, Vaccinium macrocarpon (with wide overlap in flowering time only between Andromeda and Kalmia). The pollinators (e.g. bees) are quite generalist and serve several species, so it may well be that the differentiation in flowering time has evolved to avoid competition for pollinators (Reader 1975)." (Rydin and Jeglum 2006:56)
Learn more about this functional adaptation.
- Rydin, H.; Jeglum, J. K. 2006. The Biology of Peatlands. Oxford University Press. 343 p.
- Reader RJ. 1975. Competitive relationships of some bog ericads for major insect pollinators. Canadian Journal of Botany. 53(13): 1300-1305.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/b64ed2f73849b334fd036dc90081c6b7 |
Collenchyma cells provide strength, flexibility: plants
Collenchyma cells in vascular plants support growing parts due to flexible cellulosic walls, which lignify once growth has ceased.
"In addition to the 'mechanical' cells - fibres and lignified parenchyma - a third cell type has mechanical functions. This is collenchyma. Collenchyma cells have walls which during their development and extension are mainly cellulosic. They grow with the surrounding tissue as it expands or lengthens. They are more flexible than fibres, and if they remain unlignified, as they might in association with leaf veins or midribs, or in leaf stalks (petioles), they allow for a high degree of flexibility in the organ itself. Often, after growth in length of stems has occurred, and more mechanical rigidity is an advantage, we find that the collenchyma cells become lignified, and function more as fibres." (Cutler 2005:105)
Learn more about this functional adaptation.
- Cutler, DF. 2005. Design in plants. In: Collins, MW; Atherton, MA; Bryant, JA, editors. Nature and Design. Southampton, Boston: WIT Press. p 95-124
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/86062daed0d55078ca8011dc2567b0e5 |
Folds allow efficient leaf deployment: plants
Leaves of plants maximize time exposed for photosynthesis by using various packaging schemes to fold the large leaves within the buds so they can begin photosynthesizing upon deployment.
"Leaves emerge from their buds in many different ways. Those of the cheese plant emerge tightly rolled, like perfectly furled umbrellas. Palms produce theirs neatly packed in pleats. The big fat buds of rhubarb push up through the ground and burst to reveal their young leaves squashed and crumpled. Ferns send up their shoots curled in the shape of croziers with each of the side fronds curled in its own crozier-in-miniature." (Attenborough 1995: 43-45)
Learn more about this functional adaptation.
- Attenborough, D. 1995. The Private Life of Plants: A Natural History of Plant Behavior. London: BBC Books. 320 p.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/1f9d5f8e2bf373a7f6cbb3d6c5b575ee |
Reinforced fibers provide strength: plants
Fibers in many woody plants provide mechanical strength via lignin reinforcements.
"Plant fibres occur in the wood of many plants, and because of their association with the xylem, are called xylary fibres. They are also often found in the outer part of young stems, bark and leaves, where they are called extraxylary fibres. Their main functioning is in strengthening. The common feature of fibre cells is that they are elongated and thick-walled, with lignins permeating the cellulose of the cell wall. Fibre cells normally have pointed ends (Fig. 3). They often extend in length during development, growing between cells that may not be lengthening at the same rate. Fibres may be only about 10 times longer than wide, but many are 20-30 and even up to and exceeding 100 times longer than wide. They may remain flexible, as in many extraxylary fibres, or have more limited flexibility, as in xylary fibres." (Cutler 2005:103)
Learn more about this functional adaptation.
- Cutler, DF. 2005. Design in plants. In: Collins, MW; Atherton, MA; Bryant, JA, editors. Nature and Design. Southampton, Boston: WIT Press. p 95-124
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/724da471ad5ff0041fcd9725ecbabbac |
Wood self-assembles: trees
The cell walls of wood in trees self-assemble through structural features, not biochemistry.
A better understanding of how the cell wall of wood forms will someday help wood scientists assemble wood-like composites without using trees. The current hypothesis is that the cell wall of wood does not require biochemistry to form, but self-assembles spontaneously because of structural features. Researchers are studying this process carefully, in hopes that someday wood-like materials can be produced from other plant-derived molecules. (Courtesy of the Biomimicry Guild)
Learn more about this functional adaptation.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/7d617327e1731af468cb345767bc6181 |
Lignified parenchyma cells provide strength: plants
Parenchyma cells in plants provide mechanical support when they become lignified and thick-walled.
"Sometimes axially elongated cells of the 'packing' tissue, parenchyma, become thick-walled and lignified. These have similar functions to fibres, but their ends tend not to be pointed. Often no distinction is made between this cell type and true fibres. Cells of this type make up the bulk of the strengthening tissue in bamboos. They are arranged towards the periphery of the stem, the centre of which is often hollow, with transverse septa at intervals." (Cutler 2005:103)
Learn more about this functional adaptation.
- Cutler, DF. 2005. Design in plants. In: Collins, MW; Atherton, MA; Bryant, JA, editors. Nature and Design. Southampton, Boston: WIT Press. p 95-124
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/101fcbaa20c58d5aa450ee3b1e5b819d |
Pressure sucks moisture from soil: desert plants
The roots of desert plants extract hard to remove water from soil using negative pressure.
"Plants again. Even in a desert the soil a little ways below the surface contains liquid water. It's called 'capillary water' and is often thought of as firmly stuck to soil particles. The binding, though, is as much physical as chemical - the water in the soil interstices lie in tiny recesses between soil crumbs where it has minimized its exposed interface with air (Rose 1966). For the roots of a plant to extract the water requires making more surface, and thus it takes a very great pull, one that appears as an additional (negative) component of the pressure in the vessels running up a stem or trunk. The lowest (most negative) pressures known in plants occur in desert shrubs, which must suck really hard on the ground to get any water out. The most extreme value on record is, I think, minus 120 atmospheres (Schlessinger et al. 1982) - that would hold up a column water over 1,200 meters (4,000 feet) high. So the pull needed to get water free of soil can exceed both the pull that keeps water moving in the vessels and the pull that counteracts gravity." (Vogel 2003:113)
Learn more about this functional adaptation.
- Steven Vogel. 2003. Comparative Biomechanics: Life's Physical World. Princeton: Princeton University Press. 580 p.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
Source | http://www.asknature.org/strategy/0bdb8beca31c79cdeb2aae78ed545456 |