Detritivores (also known asdetrivores,detritophages,detritus feeders ordetritus eaters) areheterotrophs that obtainnutrients by consumingdetritus (decomposing plant and animal parts as well asfeces).[1] There are many kinds ofinvertebrates,vertebrates, andplants that eat detritus or carry outcoprophagy. By doing so, all these detritivores contribute todecomposition and thenutrient cycles. Detritivores should be distinguished from otherdecomposers, such as many species ofbacteria,fungi andprotists, which are unable to ingest discrete lumps of matter. Instead, these other decomposers live by absorbing and metabolizing on a molecular scale (saprotrophic nutrition). The termsdetritivore anddecomposer are often used interchangeably, but they describe different organisms. Detritivores are usuallyarthropods and help in the process ofremineralization. Detritivores perform the first stage of remineralization, by fragmenting the dead plant matter, allowing decomposers to perform the second stage of remineralization.[2]
Plant tissues are made up of resilient molecules (e.g.cellulose,lignin,xylan) that decay at a much lower rate than other organic molecules. The activity of detritivores is the reason why there is not an accumulation of plant litter in nature.[2][3]
Detritivores are an important aspect of manyecosystems. They can live on any type of soil with an organic component, includingmarine ecosystems, where they are termed interchangeably withbottom feeders.
Typical detritivorous animals includemillipedes,springtails,woodlice,dung flies,slugs, manyterrestrialworms,sea stars,sea cucumbers,fiddler crabs, and some sedentary marinePolychaetes such as worms of the familyTerebellidae.
Detritivores can be classified into more specific groups based on their size and biomes. Macrodetritivores are larger organisms such as millipedes, springtails, and woodlouse, while microdetritivores are smaller organisms such as bacteria.[4][5]
Scavengers are not typically thought to be detritivores, as they generally eat large quantities of organic matter, but both detritivores and scavengers are the same type of cases ofconsumer-resource systems.[6] The consumption of wood, whether alive or dead, is known asxylophagy. The activity of animals feeding only on dead wood is calledsapro-xylophagy and those animals, sapro-xylophagous.
Detritivores play an (important) role as recyclers in the ecosystem'senergy flow andbiogeochemical cycles.[7] Alongside decomposers, they reintroduce vital elements such as carbon, nitrogen, phosphorus, calcium, and potassium back into the soil, allowing plants to take in these elements and use them for growth.[2] They shred the dead plant matter which releases the trapped nutrients in the plant tissues. An abundance of detritivores in the soil allows the ecosystem to efficiently recycle nutrients.[7]
Many detritivores live in maturewoodland, though the term can be applied to certainbottom-feeders inwet environments. These organisms play a crucial role inbenthic ecosystems, forming essentialfood chains and participating in thenitrogen cycle.[8] Detritivores and decomposers that reside in the desert live in burrows underground to avoid the hot surface since underground conditions provide favorable living conditions for them. Detritivores are the main organisms in clearing plant litter and recycling nutrients in the desert. Due to the limited vegetation available in the desert, desert detritivores adapted and evolved ways to feed in the extreme conditions of the desert.[3] Detritivore feeding behaviour is affected by rainfall; moist soil increases detritivore feeding and excretion.[7]
Fungi, acting as decomposers, are important in today's terrestrial environment. During theCarboniferous period, fungi and bacteria had yet to evolve the capacity to digestlignin, and so large deposits of dead plant tissue accumulated during this period, later becoming thefossil fuels.[9]
Byfeeding on sediments directly to extract the organic component, some detritivores incidentally concentratetoxicpollutants.[10]
