Springtail: Difference between revisions
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Springtails are typically found in leaf litter and other decaying organic material [6]. They mainly consume fungal hyphae and spores, but can also consume bacteria, plant material and pollen, minerals, and animal remains [7]. | Springtails are typically found in leaf litter and other decaying organic material [6]. They mainly consume fungal hyphae and spores, but can also consume bacteria, plant material and pollen, minerals, and animal remains [7]. | ||
They are one of the most abundant macroscopic animals in the world, with estimates of 100,000 individuals per square meter of ground where soil and mosses occur [8]. The only other amimals with global populations of a similar size are thought to be nematodes, crustaceans, and mites. Most springtails are difficult to see with the naked eye with few exceptions, including the snow flea [9]. Several species of springtail climb trees, and form a dominant component of canopy faunas. These species are typically smaller than soil populations of the same species by 1-2 orders of magnitude [10]. | |||
Overall, springtails are very susceptible to desiccation due to the structure of their respiratory system, although sensitivity to drought varies from species to species [11]. | |||
== Evolution == | == Evolution == | ||
Revision as of 19:47, 8 May 2018
Description
Springtails are members of the Collembola family and are relatively small, typically less than 6 millimeters in length, with as many as six abdominal segments [1]. They have a tubular appendage called a collophore, which protrudes from the first abdominal segment. The collophore used to be thought to be a stabilizing mechanism for the collembola when it jumped by sticking to the surface on which it landed. More recent research has concluded that the collophore is used in osmoregulation, water intake, and excretion [2].
Collembola that live in the upper soil layers are often referred to as Springtails because of a tail-like appendage found among most species, called the furcula. It is a forked appendage attached to the fourth segment by a structure called the retinaculum and is used for jumping when the animal is threatened; it is not used for normal locomotion [3]. In as little as 18 milliseconds the furcula can be released from the retinaculum, snapping against the substrate and flinging the springtail into the air[4]. A reason that this mechanism is not used in typical locomotion is that it’s direction is very unpredictable. When the furcula is released, the springtail is sent tumbling through the air on an arbitrary trajectory, landing randomly [3].
Springtails are able to reduce their body size by up to 30% through genetically controlled molting if temperatures are high enough. Warmer conditions increase energy needs, as well as metabolic rates, therefore a smaller body size comes with many advantages to the organism [5].
Habitat & Distribution
Springtails are typically found in leaf litter and other decaying organic material [6]. They mainly consume fungal hyphae and spores, but can also consume bacteria, plant material and pollen, minerals, and animal remains [7].
They are one of the most abundant macroscopic animals in the world, with estimates of 100,000 individuals per square meter of ground where soil and mosses occur [8]. The only other amimals with global populations of a similar size are thought to be nematodes, crustaceans, and mites. Most springtails are difficult to see with the naked eye with few exceptions, including the snow flea [9]. Several species of springtail climb trees, and form a dominant component of canopy faunas. These species are typically smaller than soil populations of the same species by 1-2 orders of magnitude [10].
Overall, springtails are very susceptible to desiccation due to the structure of their respiratory system, although sensitivity to drought varies from species to species [11].
Evolution
Environmental Impacts
References
1. Davies, W. Maldwyn (1927). "On the tracheal system of Collembola, with special reference to that of Sminthurus viridis, Lubb" (PDF). Quarterly Journal of Microscopical Science. 71 (281): 15–30.
2. Eisenbeis, G., 1982. Physiological absorption of liquid water by Collembola: absorption by the ventral tube at different salinities. Journal of Insect Physiology 28:11–20.
3. Christian, E., 1978. The jump of the springtails. Naturwissenschaften 65:495-496.
4. Piper, Ross (2007). Extraordinary animals: an encyclopedia of curious and unusual animals. Santa Barbara, California: Greenwood Press.
5. "The incredible shrinking springtail". Science. 341 (6149): 945. 30 August 2013. doi:10.1126/science.341.6149.945-a.
6. Hopkin, Stephen P. (1997). "The biology of the Collembola (springtails): the most abundant insects in the world" (PDF). Natural History Museum.
7. Chen, Benrong; Snider, Richard J. & Snider, Renate M. (1996). "Food consumption by Collembola from northern Michigan deciduous forest" (PDF). Pedobiologia. 40 (2): 149–161.
8. Ponge, Jean-François; Arpin, Pierre; Sondag, Francis & Delecour, Ferdinand (1997). "Soil fauna and site assessment in beech stands of the Belgian Ardennes" (PDF). Canadian Journal of Forest Research. 27 (12): 2053–2064. doi:10.1139/cjfr-27-12-2053.
9. Island Creek Elementary School. "Snow Flea. Hypogastrura nivicola". Study of Northern Virginia Ecology. Fairfax County Public Schools.
10. Shaw, Peter; Ozanne, Claire; Speight, Martin & Palmer, Imogen (2007). "Edge effects and arboreal Collembola in coniferous plantations" (PDF). Pedobiologia. 51 (4): 287–293. doi:10.1016/j.pedobi.2007.04.010.
11. Nickerl, Julia; Helbig, Ralf; Schulz, Hans-Jürgen; Werner, Carsten & Neinhuis, Christoph (2013). "Diversity and potential correlations to the function of Collembola cuticle structures" (PDF). Zoomorphology. 132 (2): 183–195. doi:10.1007/s00435-012-0181-0.