Durable Adhesive Traps Prey

long, thin green and dark red leaves have small spikes pointing out, a fly is stuck on one of the center leaves

Biological Strategy

Flypaper plant

AskNature Team

Image: Tony Rebelo / Wikimedia Commons / CC BY - Creative Commons Attribution alone

Attach Permanently

A living system can conserve energy by attaching permanently to a particular site because it can take advantage of resources that come its way, rather than expending energy to move to resources. A permanent attachment, intended to last the lifetime of the living system, creates special challenges. For example, physical mechanisms, such as the anchor that holds a marine algae to the ocean’s bottom, must be able to withstand forces that can pull it off its substrate. Chemical mechanisms, such as a barnacle’s glue, must avoid both physical and chemical breakdown, such as being dissolved by water.

Search this Function

Attach Temporarily

Living systems must sometimes, temporarily, stay in one place, climb or otherwise move around, or hold things together. This entails attaching temporarily with the ability to release, which minimizes energy and material use. Some living systems repeatedly attach, detach, and reattach for an extended time, such as over their lifetimes. Despite being temporary, these attachments must withstand physical and other forces until they have achieved their purpose. Therefore, living systems have adapted attachment mechanisms optimized for the amount of time or number of times they must be used. An example is the gecko, which climbs walls by attaching its toes for less than a second. Other examples include insects that attach their eggs to a leaf until they hatch, and insects whose wings temporarily attach during flight but separate after landing.

Search this Function

Flowering Plants

Clade Angiosperms (“receptacle seed”): Dandelions, oaks, grasses, cacti, apples

With 416 families containing some 300,000 known species, angiosperms are the most diverse group of plants, and they can be found around the globe in a wide variety of habitats. They are characterized by seeds that grow enclosed in ovaries, which are enclosed in flowers. The floral organs then develop into fruits of myriad kinds and dimensions, from simple seed casings on maples to elaborate fleshy growths like papayas. The oldest flower known from fossils, Montsechia vidalii, appeared during the Jurassic Period 130 million years ago. They are the primary food source for herbivorous animals, which in turn makes them the indirect food source for carnivores as well.

Search this Living System

Traps of the flypaper plant capture prey via a super sticky, superbly water repellant, long lasting, adhesive.

The adhesive substance produced by flypaper plants, Roridula gorgonias, is extremely sticky, long lasting, and water tolerant. They remain hydrated and functionally adhesive even after prolonged exposure to dry environments. Flypaper plants also cultivate populations of symbiotic insects within its traps that must be able to resist the adhesive. The insect’s shells are uniformly coated with a specific type of grease rendering the adhesive powerless to trap them. Other insects tend to produce more patchy grease layers that leave room for the adhesive to stick to their exposed cuticle.

Image: Alex Lomas /

Last Updated October 16, 2016

References

“It has been previously demonstrated that the secretion of R.[Roridula] gorgonias differs remarkably from the aqueous mucilage of flypaper traps of other carnivorous plants belonging to the genera Byblis, Drosera, Drosophyllum, and Pinguicula. Various triterpenoids, acylglycerides, and flavonoids have been found in the R. gorgonias adhesive secretion. The secretion is water-insoluble and capable of maintaining ovoid or spherical shape and adhesive properties even under water. The pellucid secretion droplets have been observed to retain their properties for an indefinitely long time on dead and dried-up leaves or even on leaves preserved in formalin. The secretion remained adhesive and viscoelastic even after storing dead, dry R. gorgonias plants for 5 years.” (Voigt and Gorb 2010: 1511)

“Resinous secretion of R. gorgonias seems to be responsible for several functions: (1) The mixture of triterpenoids and acylglycerids causes its consistency similar to sticky syrup or to so-called pseudoliquid phase similar to that observed in commercial pressure-sensitive adhesives. Such consistency of secretion probably contributes to its visco-elastic properties. The resin obviously functions as the adhesive component of the efficient insect trap. (2) Since resin droplets, released on trichome tips, are shiny and glistening, they attract insects prior to their capture. (3) As mentioned earlier, such a shiny surface also enhances light reflection therewith supporting the reduction of leaf temperature in a hot environment. (4) The hydrophobic nature of the secretion results in the reduction of water loss. (5) The robustness of the secretion to abiotic environmental factors could lead to saving energy, because of lower glandular activity necessary to fulfill the aforementioned functions. The renewal of the secretion is very limited, as we have observed in previous studies on adhesion of R. gorgonias trichomes. (6) Glandular trichomes may additionally offer protection against predatory insect attacks and animal grazing.” (Voigt and Gorb 2010: 1514)

Journal article

Desiccation resistance of adhesive secretion in the protocarnivorous plant Roridula gorgonias as an adaptation to periodically dry environment

Planta | 23/09/2010 | Dagmar Voigt, Stanislav Gorb

embedly preview

Reference

Journal article

An insect trap as habitat: cohesion-failure mechanism prevents adhesion of Pameridea roridulae bugs to the sticky surface of the plant Roridula gorgonias

Journal of Experimental Biology | 08/08/2008 | D. Voigt, S. Gorb

embedly preview

AskNature