Eating behavior Specific feeding (
foraging) strategies and mechanisms are employed to match specific
niches.
Herbivorous and
detritivorous species fragment biological material present in soil and leaf litter, supporting
decomposition and increasing the availability of
nutrients for plants and various species of microbes and fungi. Carnivorous species maintain populations of small invertebrates such as
nematodes,
rotifers, and other collembolan species. Some springtail species like
Anurophorus laricis can form mutually beneficial relationships with
lichens, using them for shelter while feeding on surrounding free-living
algae, which helps reduce competition between algae and lichens for space and nutrients. For finding their preferred food in light-free and complex environments like litter and soil layers Collembola use
olfactory cues such as the
odors emitted by fungi and other food sources as attractors. Directional movement towards the food source has been recorded by
image analysis in
laboratory experiments. However, other experiments showed that attraction and consumption were often, but not always correlated, and that preferred fungal strains were not necessarity those that optimize performances in
reproduction (
fitness), growth and
survival.
Predators Springtails are consumed by
mesostigmatan mites in various families, including
Ascidae,
Laelapidae,
Parasitidae,
Rhodacaridae and
Veigaiidae. Cave-dwelling springtails are a food source for
spiders and
harvestmen in the same environment, such as the endangered harvestman
Texella reyesi. Predators also include various
soil centipedes. Jumping, using the furcula as a spring, is the most common way to avoid predation, but jump escape cannot be performed easily in concealed environments such as litter, and more especially soil layers. To protect themselves against predators, some species without jumping abilities have evolved chemical defenses.
Distribution Springtails are
cryptozoa frequently found in
leaf litter and other decaying material, In a mature deciduous woodland in temperate climate, leaf litter and vegetation typically support 30 to 40 species of springtails, and in the tropics the number may be over 100. essentially everywhere on Earth where soil and related habitats (
moss cushions, fallen
wood,
grass tufts,
ant and
termite nests) occur. Only
nematodes,
crustaceans, and
mites are likely to have global populations of similar magnitude, and each of those groups except mites is more inclusive. Though
taxonomic rank cannot be used for absolute comparisons, it is notable that nematodes are a
phylum and crustaceans a
subphylum. Most springtails are small and difficult to see by casual observation, but some springtails, like
snow fleas, are readily observed on warm winter days when it is active and its dark color contrasts sharply with a background of snow. In addition, a few species routinely climb trees and form a dominant component of
canopy fauna, where they may be collected by beating or insecticide
fogging. In temperate regions, a few species (e.g.
Anurophorus laricis,
Entomobrya albocincta,
Xenylla xavieri,
Hypogastrura arborea) are almost exclusively arboreal. dispersal limitation and probable species
interactions. Some species have been shown to exhibit negative or positive '' sp. on leaf As a group, springtails are highly sensitive to
desiccation, because of their tegumentary
respiration, although some species with thin,
permeable cuticles have been shown to resist severe
drought by regulating the
osmotic pressure of their
body fluid. The gregarious behaviour of Collembola, mostly driven by the attractive power of
pheromones excreted by adults, gives more chance to every juvenile or adult individual to find suitable, better protected places, where
desiccation could be avoided and
reproduction and
survival rates (thereby
fitness) could be kept at an optimum. Sensitivity to drought varies from species to species and increases during
ecdysis. Given that springtails
moult repeatedly during their entire life (an
ancestral character in
Hexapoda) they spend much time in concealed
micro-sites where they can find protection against
desiccation and
predation during
ecdysis, an advantage reinforced by
synchronized
moulting. The high
humidity of many
caves also favours springtails and there are numerous cave adapted species, including one,
Plutomurus ortobalaganensis living down the
Krubera Cave. '' on water The horizontal distribution of springtail species is affected by
environmental factors which act at the
landscape scale, such as soil
acidity,
moisture and
light. Altitudinal changes in species distribution can be at least partly explained by increased
acidity at higher elevation. Moisture requirements, among other ecological and behavioural factors, explain why some species cannot live
aboveground, or retreat in the soil during dry seasons, but also why some
epigeal springtails are always found in the vicinity of
ponds and
lakes, such as the hygrophilous
Isotomurus palustris.
Adaptive features, such as the presence of a fan-like wettable mucro, allow some species to move at the surface of water in
freshwater and
marine environments.
Podura aquatica, a unique representative of the family
Poduridae (and one of the first springtails to have been described by
Carl Linnaeus), spends its entire life at the surface of water, its wettable eggs dropping in water until the non-wettable first instar hatches then surfaces. A few genera are capable of being submerged, and after molting young springtails lose their
water repellent properties and are able to survive submerged under water. In a variegated landscape, made of a patchwork of closed (
woodland) and open (
meadows,
cereal crops) environments, most
soil-dwelling species are not specialized and can be found everywhere, but most
epigeal and
litter-dwelling species are attracted to a particular environment, either forested or not. As a consequence of
dispersal limitation,
landuse change, when too rapid, may cause the local disappearance of slow-moving,
specialist species, a phenomenon the measure of which has been called
colonisation credit.
Role in turfgrass ecosystems In managed
turfgrass and urban lawn ecosystems, Collembola function as "thatch busters", playing a significant role in the decomposition of
thatch—the layer of living and dead organic matter between the green vegetation and the soil surface. A common model species in North American turfgrass is
Isotomiella minor.
Relationship with humans '' sp. from Germany Springtails are well known as
pests of some agricultural crops.
Sminthurus viridis, the
lucerne flea, has been shown to cause severe damage to agricultural crops, and is considered as a pest in Australia.
Onychiuridae are also known to feed on
tubers and to damage them to some extent. However, by their capacity to carry spores of
mycorrhizal fungi and
mycorrhiza helper bacteria on their tegument, soil springtails play a positive role in the establishment of plant-fungal
symbioses and thus are beneficial to agriculture. They also contribute to controlling plant
fungal diseases through their active consumption of
mycelia and
spores of
damping-off and
pathogenic fungi. It has been suggested that they could be reared to be used for the control of
pathogenic fungi in
greenhouses and other indoor cultures. Springtails sometimes find their way inside human
living spaces. However, most
pesticides are not effective against them and moisture-removal strategies are the best line of defense to combat
infestations. Various sources and publications have suggested that some springtails may
parasitize humans, but this is entirely inconsistent with their biology, and no such phenomenon has ever been scientifically confirmed, though it has been documented that the scales or hairs from springtails can cause
irritation when rubbed onto the
skin. They may sometimes be abundant indoors in damp places such as
bathrooms and
basements, and incidentally found on one's person. More often, claims of persistent human skin infection by springtails may indicate a
neurological problem, such as
delusional parasitosis, a
psychological rather than
entomological problem. Researchers themselves may be subject to psychological phenomena. For example, a publication in 2004 claiming that springtails had been found in skin samples was later determined to be a case of
pareidolia; that is, no springtail specimens were actually recovered, but the researchers had digitally enhanced photos of sample debris to create images resembling small arthropod heads, which then were claimed to be springtail remnants. However, Steve Hopkin reports one instance of an entomologist
aspirating an
Isotoma species and in the process accidentally inhaling some of their eggs, which hatched in his nasal cavity and made him quite ill until they were flushed out. Springtail species cited in
allegations of biological warfare in the Korean War were
Isotoma (Desoria) negishina (a local species) and the "white rat springtail"
Folsomia candida. Captive springtails are often kept in a
terrarium as part of a
clean-up crew.
Ecotoxicology laboratory animals Springtails are currently used in laboratory tests for the early detection of
soil pollution.
Acute and
chronic toxicity tests have been performed by researchers, mostly using the
parthenogenetic isotomid Folsomia candida. These tests have been standardized. Details on a
ringtest, on the biology and
ecotoxicology of
Folsomia candida and comparison with the sexual nearby species
Folsomia fimetaria (sometimes preferred to
Folsomia candida) are given in a document written by Paul Henning Krogh. Care should be taken that different
strains of the same species may be conducive to different results.
Avoidance tests have been also performed. They have been standardized, too. Avoidance tests are complementary to toxicity tests, but they also offer several advantages: they are more rapid (thus cheaper), more sensitive and they are environmentally more reliable, because in the real world Collembola move actively far from pollution spots. It may be hypothesized that the soil could become locally depauperated in animals (and thus improper to normal use) while below thresholds of toxicity. Contrary to
earthworms, and like many
insects and
molluscs, Collembola are very sensitive to
herbicides and thus are threatened in
no-tillage agriculture, which makes a more intense use of herbicides than
conventional agriculture. The springtail
Folsomia candida is also becoming a
genomic model organism for soil toxicology. With
microarray technology the expression of thousands of genes can be measured in parallel. The
gene expression profiles of
Folsomia candida exposed to environmental
toxicants allow fast and sensitive detection of
pollution, and additionally clarifies molecular mechanisms causing
toxicity. Collembola have been found to be useful as
bio-indicators of
soil quality. Laboratory studies have been conducted that validated that the
jumping ability of springtails can be used to evaluate the soil quality of Cu- and Ni-polluted sites. ==Climate warming impact==