This is a classic 'Applied Biology' question. While standard books (Shankar/NCERT) only explicitly list Earthworms, the question demands you apply the definition of 'Detritivore' (eater of dead organic matter) to eliminate obvious predators. It tests observation and common sense over rote memorization.
How this question is built
This question can be broken into the following sub-statements.
Tap a statement sentence to jump into its detailed analysis.
Statement 1
Are earthworms detritivores (organisms that feed on decomposing organic matter)?
Origin: Direct from books
Fairness: Straightforward
Book-answerable
From standard books
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
Presence: 5/5
“(ii) Micro consumers - Saprotrophs (decomposers or osmotrophs)
• They are bacteria and fungi which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. • The products of decomposition such as inorganic nutrients which are released in the ecosystem are reused by producers and thus recycled. • Earthworm and certain soil organisms (such as nematodes, and arthropods) are detritus feeders and help in the decomposition of organic matter and are called detrivores.”
Why this source?
- Explicitly names earthworms as detritus feeders (detrivores).
- Links earthworms to decomposition of organic matter and nutrient recycling.
Indian Economy, Vivek Singh (7th ed. 2023-24) > Chapter 11: Agriculture - Part II > Differences between Organic Farming and ZBNF: > p. 349
Presence: 4/5
“In organic farming, organic fertilizers and manures like compost, vermicompost, cow dung manure, etc. are used and added to farmlands from external sources. While in natural farming, neither chemical nor organic fertilizers are added to the soil. In fact, no external fertilizers are added to soil or given to plants whatsoever. In natural farming, decomposition of organic matter by microbes and earthworms is encouraged right on the soil surface itself, which gradually adds nutrition in the soil, over the period.”
Why this source?
- Describes decomposition of organic matter by microbes and earthworms in farming practices.
- Connects earthworm activity to generation of soil nutrition (vermicompost context).
FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 5: Geomorphic Processes > Biological Activity > p. 45
Presence: 3/5
“Further, bacteria and other soil organisms take gaseous nitrogen from the air and convert it into a chemical form that can be used by plants. This process is known as nitrogen fixation. Rhizobium, a type of bacteria, lives in the root nodules of leguminous plants and fixes nitrogen beneficial to the host plant. The influence of large animals like ants, termites, earthworms, rodents etc., is mechanical, but, it is nevertheless important in soil formation as they rework the soil up and down. In case of earthworms, as they feed on soil, the texture and chemistry of the soil that comes out of their body changes.”
Why this source?
- Explains earthworms feed on soil and mechanically rework it, altering texture and chemistry.
- Implies a role in processing organic material and contributing to soil formation.
Statement 2
Are jellyfish detritivores (organisms that feed on decomposing organic matter)?
Origin: Weak / unclear
Fairness: Borderline / guessy
Indirect textbook clues
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
Strength: 5/5
“It starts from dead organic matter, decaying animals and plant bodies consumed by the microorganisms and then to detritus feeding organisms called detrivores or decomposers and to other predators. The distinction between these two food chains is the source of energy for the first level consumers. In the grazing food chain the primary source of energy is living plant biomass while in the detritus food charn the source of energy is dead organic matter or detritus. The two food cliains are linked. The,initial energy source for detritus food chain is the waste materials and dead organic matter from the grazing food chain.”
Why relevant
Defines the detritus food chain: first consumers take dead organic matter and are called detritus-feeding organisms (detrivores), establishing what behaviour qualifies as detritivory.
How to extend
A student can compare this definition to described jellyfish feeding behaviour (do they consume dead organic matter as first-level consumers?) to judge if jellyfish fit the detritivore role.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
Strength: 4/5
“should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, unable to ingest discrete lumps of mattel instead live by absorbing and metaboiising on a molecular scale. However, the terms detritivore and decomposer are often used interchangeably • The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment. • Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water. • The gene pool is the complete set of unique alleles in a species. • Microclimate is a local atmospheric zone where the climate differs from the surrounding area.”
Why relevant
Notes a practical distinction: many decomposers (bacteria, fungi, protists) absorb on a molecular scale, while the terms detritivore and decomposer are often used interchangeably but detritivores ingest discrete lumps of matter.
How to extend
Use this rule to check whether jellyfish ingest particulate detritus (lumps) versus capturing live prey or filtering—if they ingest particles, they might be detritivores by this criterion.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
Strength: 3/5
“(ii) Micro consumers - Saprotrophs (decomposers or osmotrophs)
• They are bacteria and fungi which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. • The products of decomposition such as inorganic nutrients which are released in the ecosystem are reused by producers and thus recycled. • Earthworm and certain soil organisms (such as nematodes, and arthropods) are detritus feeders and help in the decomposition of organic matter and are called detrivores.”
Why relevant
Gives examples of detritus feeders (earthworm, nematodes, arthropods) that actively consume detritus, showing typical detritivore taxa and feeding modes.
How to extend
Compare typical detritivore taxa and feeding anatomy/behaviour with jellyfish morphology/feeding methods (from external sources) to assess plausibility.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 14: Marine Organisms > 14.3. ZOOPLANKTON > p. 209
Strength: 4/5
“• Zooplankton play vital role in food web of the lcod chain, nutrient recycling, and in transfer of organic matter from primary producers to serondary consumers like fishes. • They are more abundant within mangrove waterways than in adjacent coastal waters, and a large proportion of the juvenile fish of mangrove habitat are zooplanktivorous. • The zooplanckton determine the quantum of fish stock.”
Why relevant
Describes zooplankton roles in nutrient recycling and transfer of organic matter in marine food webs, linking small planktonic consumers to detritus and nutrient pathways.
How to extend
Since jellyfish are often part of the planktonic community, a student could check whether planktonic feeding modes include detritivory and whether jellyfish are listed among detritus-feeding zooplankton.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Decomposers or Saprophytes > p. 31
Strength: 3/5
“At the lowest level of consumers are the primary consumers (the snail, insects, and fshes). At the next level are the secondary consumers (the mammals, birds, and larger fshes), which feed on the primary consumers. A still higher level of feeding occurs in the salt marsh ecosystem, as marsh hawks and owls consume the smaller animals below them in the food web. Te decomposers feed on detritus, or decaying organic matter, derived from all levels. Tey are largely microscopic organisms and bacteria. At each level of energy fow in the food web, energy is lost to respiration. In fact, plants not only store energy, they also consume some of this energy by converting carbohydrates to derive for their other operations.”
Why relevant
States decomposers feed on detritus and are largely microscopic, emphasizing that many detritus processors are microbes rather than macroscopic predators.
How to extend
Use this to weigh whether a macroscopic gelatinous predator like a jellyfish is more likely a predator/consumer of live prey than a decomposer/detritivore, prompting targeted lookup of jellyfish diet.
Statement 3
Are millipedes detritivores (organisms that feed on decomposing organic matter)?
Origin: Weak / unclear
Fairness: Borderline / guessy
Indirect textbook clues
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
Strength: 4/5
“(ii) Micro consumers - Saprotrophs (decomposers or osmotrophs)
• They are bacteria and fungi which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. • The products of decomposition such as inorganic nutrients which are released in the ecosystem are reused by producers and thus recycled. • Earthworm and certain soil organisms (such as nematodes, and arthropods) are detritus feeders and help in the decomposition of organic matter and are called detrivores.”
Why relevant
Explicitly lists 'arthropods' among soil organisms termed detritus feeders (detrivores), alongside earthworms and nematodes.
How to extend
A student who knows millipedes are arthropods could use this pattern to suspect millipedes may be detritivores and then check habitat/feeding habits.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
Strength: 4/5
“It starts from dead organic matter, decaying animals and plant bodies consumed by the microorganisms and then to detritus feeding organisms called detrivores or decomposers and to other predators. The distinction between these two food chains is the source of energy for the first level consumers. In the grazing food chain the primary source of energy is living plant biomass while in the detritus food charn the source of energy is dead organic matter or detritus. The two food cliains are linked. The,initial energy source for detritus food chain is the waste materials and dead organic matter from the grazing food chain.”
Why relevant
Defines the detritus food chain as beginning with dead organic matter consumed by 'detritus feeding organisms called detrivores'.
How to extend
Knowing where millipedes are found (e.g., leaf litter/soil) and that detritivores consume detritus, a student could infer millipedes might belong to this group and verify by species-level feeding info.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Decomposers or Saprophytes > p. 31
Strength: 3/5
“At the lowest level of consumers are the primary consumers (the snail, insects, and fshes). At the next level are the secondary consumers (the mammals, birds, and larger fshes), which feed on the primary consumers. A still higher level of feeding occurs in the salt marsh ecosystem, as marsh hawks and owls consume the smaller animals below them in the food web. Te decomposers feed on detritus, or decaying organic matter, derived from all levels. Tey are largely microscopic organisms and bacteria. At each level of energy fow in the food web, energy is lost to respiration. In fact, plants not only store energy, they also consume some of this energy by converting carbohydrates to derive for their other operations.”
Why relevant
States decomposers feed on detritus/decaying organic matter and gives insects and snails as examples of consumers in lower levels.
How to extend
Using the example list of lower-level consumers (insects/snails) one could analogously consider millipedes (another small soil arthropod) as candidate detritivores pending direct feeding evidence.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
Strength: 3/5
“should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, unable to ingest discrete lumps of mattel instead live by absorbing and metaboiising on a molecular scale. However, the terms detritivore and decomposer are often used interchangeably • The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment. • Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water. • The gene pool is the complete set of unique alleles in a species. • Microclimate is a local atmospheric zone where the climate differs from the surrounding area.”
Why relevant
Notes the terms 'detritivore' and 'decomposer' are often used interchangeably and distinguishes organisms that ingest particulate detritus from those that absorb molecules.
How to extend
If millipedes ingest decaying plant matter (a basic natural-history fact a student might recall), this distinction supports classifying them as detritivores rather than only microbial decomposers.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > 1. Biotic (Living) Components > p. 17
Strength: 2/5
“• (b) Consumers or heterotrophs: Tese include animals which can be primary consumers (herbivores) or secondary or tertiary consumers (carnivores and omnivores).• (c) Decomposers or detritus: Bacteria, fungi and insects which degrade and decompose organic matter of all types and restore nutrients to the environment are known as decomposers or detritus. Te producers will then consume the nutrients, thus completing the organic cycle (Fig. 1.5).”
Why relevant
Explains decomposers/detritus organisms degrade organic matter and restore nutrients, framing what functional criteria define detritivores.
How to extend
A student could apply this functional definition to millipedes by checking whether they feed on/degrade organic detritus in ecosystems.
Statement 4
Are seahorses detritivores (organisms that feed on decomposing organic matter)?
Origin: Weak / unclear
Fairness: Borderline / guessy
Indirect textbook clues
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
Strength: 4/5
“(ii) Micro consumers - Saprotrophs (decomposers or osmotrophs)
• They are bacteria and fungi which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. • The products of decomposition such as inorganic nutrients which are released in the ecosystem are reused by producers and thus recycled. • Earthworm and certain soil organisms (such as nematodes, and arthropods) are detritus feeders and help in the decomposition of organic matter and are called detrivores.”
Why relevant
Gives a clear definition and examples of detritus feeders (detrivores) as organisms that consume dead organic matter and lists typical detritivore examples (earthworm, nematodes, arthropods).
How to extend
A student could compare seahorses to these example detritivores (are seahorses similar in feeding mode/anatomy/behaviour?) or look up standard facts on seahorse feeding to see if they ingest detritus like earthworms do.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
Strength: 4/5
“It starts from dead organic matter, decaying animals and plant bodies consumed by the microorganisms and then to detritus feeding organisms called detrivores or decomposers and to other predators. The distinction between these two food chains is the source of energy for the first level consumers. In the grazing food chain the primary source of energy is living plant biomass while in the detritus food charn the source of energy is dead organic matter or detritus. The two food cliains are linked. The,initial energy source for detritus food chain is the waste materials and dead organic matter from the grazing food chain.”
Why relevant
Explains the detritus food chain: its first consumers obtain energy from dead organic matter, distinguishing it from grazing chains based on living plant biomass.
How to extend
One could place seahorses within a marine food‑web (using basic external knowledge of food chains) to judge whether their energy source is dead organic matter or living prey.
Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Decomposers or Saprophytes > p. 31
Strength: 3/5
“At the lowest level of consumers are the primary consumers (the snail, insects, and fshes). At the next level are the secondary consumers (the mammals, birds, and larger fshes), which feed on the primary consumers. A still higher level of feeding occurs in the salt marsh ecosystem, as marsh hawks and owls consume the smaller animals below them in the food web. Te decomposers feed on detritus, or decaying organic matter, derived from all levels. Tey are largely microscopic organisms and bacteria. At each level of energy fow in the food web, energy is lost to respiration. In fact, plants not only store energy, they also consume some of this energy by converting carbohydrates to derive for their other operations.”
Why relevant
States decomposers feed on detritus and are largely microscopic (bacteria, fungi), emphasising that many detritus processors are not larger predatory animals.
How to extend
A student could check whether seahorses feed by microscopic absorption/decomposition vs. active ingestion of prey, using standard biological descriptions of fish feeding methods.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
Strength: 3/5
“should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, unable to ingest discrete lumps of mattel instead live by absorbing and metaboiising on a molecular scale. However, the terms detritivore and decomposer are often used interchangeably • The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment. • Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water. • The gene pool is the complete set of unique alleles in a species. • Microclimate is a local atmospheric zone where the climate differs from the surrounding area.”
Why relevant
Notes distinction and overlap between terms 'detritivore' and 'decomposer', and that many decomposers are microbes that absorb molecules rather than ingest particles.
How to extend
Using this rule, one could test if seahorses employ absorption/metabolic decomposition (like microbes) or mechanical ingestion, to assess if 'detritivore' applies.
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 14: Marine Organisms > 14.3. ZOOPLANKTON > p. 209
Strength: 4/5
“• Zooplankton play vital role in food web of the lcod chain, nutrient recycling, and in transfer of organic matter from primary producers to serondary consumers like fishes. • They are more abundant within mangrove waterways than in adjacent coastal waters, and a large proportion of the juvenile fish of mangrove habitat are zooplanktivorous. • The zooplanckton determine the quantum of fish stock.”
Why relevant
Describes the role of zooplankton in transferring organic matter to secondary consumers (fishes), indicating a common marine trophic pathway involving live small organisms rather than detritus.
How to extend
A student could use this pattern to hypothesize that marine fishes (including seahorses) may feed on zooplankton/organisms in the grazing/consumer chain rather than being detritivores, then verify seahorse diet.
Statement 5
Are woodlice detritivores (organisms that feed on decomposing organic matter)?
Origin: Weak / unclear
Fairness: Borderline / guessy
Indirect textbook clues
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
Strength: 5/5
“(ii) Micro consumers - Saprotrophs (decomposers or osmotrophs)
• They are bacteria and fungi which obtain energy and nutrients by decomposing dead organic substances (detritus) of plant and animal origin. • The products of decomposition such as inorganic nutrients which are released in the ecosystem are reused by producers and thus recycled. • Earthworm and certain soil organisms (such as nematodes, and arthropods) are detritus feeders and help in the decomposition of organic matter and are called detrivores.”
Why relevant
States that certain soil organisms, such as nematodes and arthropods, are detritus feeders (detrivores).
How to extend
A student who knows that woodlice are terrestrial arthropods could reasonably infer they may belong to this group and so test woodlouse feeding habits or habitat (leaf litter, decaying matter).
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
Strength: 4/5
“It starts from dead organic matter, decaying animals and plant bodies consumed by the microorganisms and then to detritus feeding organisms called detrivores or decomposers and to other predators. The distinction between these two food chains is the source of energy for the first level consumers. In the grazing food chain the primary source of energy is living plant biomass while in the detritus food charn the source of energy is dead organic matter or detritus. The two food cliains are linked. The,initial energy source for detritus food chain is the waste materials and dead organic matter from the grazing food chain.”
Why relevant
Defines the detritus food chain as beginning with dead organic matter and names detritus-feeding organisms (detrivores) as consumers in that chain.
How to extend
Use this rule to check whether woodlice occupy the first consumer level on detritus food chains in terrestrial ecosystems (e.g., in leaf litter studies).
Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
Strength: 4/5
“should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, unable to ingest discrete lumps of mattel instead live by absorbing and metaboiising on a molecular scale. However, the terms detritivore and decomposer are often used interchangeably • The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water and other necessities available in the environment. • Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water. • The gene pool is the complete set of unique alleles in a species. • Microclimate is a local atmospheric zone where the climate differs from the surrounding area.”
Why relevant
Clarifies terminology: distinguishes decomposers and notes the terms detritivore and decomposer are often used interchangeably.
How to extend
A student can apply this to interpret observational or experimental evidence of woodlice breaking down organic matter as qualifying them as detritivores/decomposers.
Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 12: How Nature Works in Harmony > 12.6 What Happens to Waste in Nature? > p. 201
Strength: 3/5
“important nutrients to the soil. You can also find tiny insects, such as beetles and flies, on animal droppings—like elephant dung—as they help break it down and recycle nutrients, back into the environment. This process is called decomposition and the organisms carrying out the process are called decomposers or saprotrophs (sapro= rotten + trophs = food). Plants grow in soil and many of the nutrients in soil come from the decomposition process. Thus, decomposers play an important role in recycling nutrients. In nature, nothing is wasted—everything is reused. Does nature really waste anything?”
Why relevant
Gives examples of small insects (beetles, flies) found on dung that help break it down and are called decomposers/saprotrophs.
How to extend
By analogy, examine whether woodlice are commonly found on/consume decaying plant matter or dung, supporting classification as detritivores.
Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 12: How Nature Works in Harmony > Snapshots > p. 207
Strength: 3/5
“Chapter 12 — How Nature Works in Harmony 207 • • Habitats have biotic components (plants, animals, microbes) and abiotic components (air, water, soil, temperature).• The interaction between biotic components and abiotic components in an area forms an ecosystem.• Ecosystems can be terrestrial (forests, grasslands, deserts) or aquatic (ponds, lakes, sea, oceans).• Organisms often classified as producers (plants), consumers (herbivores, carnivores, omnivores), and decomposers (bacteria, fungi).• Producers make their own food, while consumers eat plants or animals. Decomposers break down dead matter and recycle nutrients.• Food chains depict who eats whom in an ecosystem, and food webs show how these chains are interconnected.”
Why relevant
Summarises that ecosystems include producers, consumers, and decomposers, with decomposers breaking down dead matter and recycling nutrients.
How to extend
Use this general role to place woodlice within ecosystem nutrient-recycling roles by observing whether they contribute to breakdown of dead organic matter.
Pattern takeaway:
UPSC mixes terrestrial and marine examples to test a single functional concept. They reward 'Natural History' logic: knowing that Jellyfish sting (hunt) and Seahorses ambush prey allows you to eliminate them without knowing exactly what a Woodlouse is.
How you should have studied
- [THE VERDICT]: Applied Sitter. Earthworm is textbook knowledge; Jellyfish and Seahorses are obvious predators if you visualize them.
- [THE CONCEPTUAL TRIGGER]: Ecology > Ecosystem Functions > Trophic Levels (Detritus Food Chain vs. Grazing Food Chain).
- [THE HORIZONTAL EXPANSION]: Memorize the 'Clean-up Crew': Terrestrial (Millipedes, Woodlice, Dung Beetles, Springtails, Termites) vs. Marine (Sea Cucumbers, Fiddler Crabs, Polychaete worms). Contrast with 'Lookalikes' that are predators: Centipedes (venomous hunters), Spiders.
- [THE STRATEGIC METACOGNITION]: Do not stop at the definition. When reading 'Detritivore', ask: 'Who else does this job in the ocean? In the forest?' Classify animals by their 'tools': Stinging cells (Jellyfish) = Hunter; Chewing mouthparts in soil (Millipede) = Recycler.
Concept hooks from this question
👉 Detritivores vs decomposers
💡 The insight
Detritivores ingest and fragment dead organic matter while decomposers (microbes) chemically break it down at a molecular scale.
High-yield for ecology questions: distinguishes functional roles in nutrient cycling and food chains, helps answer MCQs on trophic categories and recycling processes. Links to topics on decomposition, soil biology and ecosystem functions.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
🔗 Anchor: "Are earthworms detritivores (organisms that feed on decomposing organic matter)?"
👉 Detritus food chain
💡 The insight
The detritus food chain begins with dead organic matter and includes detritivores (like earthworms) that consume that material and transfer energy upward.
Frequently tested in ecosystem/function questions; understanding it clarifies differences with grazing food chain and shows how energy and nutrients are recycled. Useful for linking biodiversity, ecosystem services and agricultural sustainability topics.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
🔗 Anchor: "Are earthworms detritivores (organisms that feed on decomposing organic matter)?"
👉 Earthworms and soil health (vermicomposting)
💡 The insight
Earthworms process organic wastes, alter soil texture and chemistry, and are employed in vermicomposting to improve soil nutrition.
Directly relevant to agriculture and environment mains/GS papers: explains sustainable soil management, organic farming practices and nutrient replenishment. Enables answers on soil fertility interventions and ecosystem services of soil fauna.
📚 Reading List :
- Indian Economy, Vivek Singh (7th ed. 2023-24) > Chapter 11: Agriculture - Part II > Differences between Organic Farming and ZBNF: > p. 349
- FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 5: Geomorphic Processes > Biological Activity > p. 45
🔗 Anchor: "Are earthworms detritivores (organisms that feed on decomposing organic matter)?"
👉 Detritivores versus decomposers (functional difference)
💡 The insight
Detritivores ingest and physically consume discrete detritus particles, whereas decomposers chemically break down organic matter by absorption.
This distinction is high‑yield for ecology questions because many stems ask which organisms perform ingestion versus absorption of dead organic matter; it connects to trophic role classification and helps eliminate wrong options in MCQs on nutrient cycling and food chains.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
🔗 Anchor: "Are jellyfish detritivores (organisms that feed on decomposing organic matter)?"
👉 Detritus food chain vs grazing (green) food chain
💡 The insight
The detritus food chain is driven by dead organic matter and waste, while the grazing food chain is based on living plant biomass.
Understanding these two linked food chains is essential for questions on ecosystem functions, energy flow, and nutrient recycling; it allows candidates to classify organism roles and trace energy sources in ecosystem scenarios.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > ii) Detritus food chain > p. 12
🔗 Anchor: "Are jellyfish detritivores (organisms that feed on decomposing organic matter)?"
👉 Common detritivore and decomposer groups
💡 The insight
Typical detritus feeders include earthworms, nematodes and certain arthropods, while decomposers commonly include bacteria and fungi.
Memorising representative taxa helps answer direct identification questions and contrasts (e.g., which of the following is a detritivore); it links to soil ecology, decomposition rates and ecosystem recycling topics frequently tested in prelims and mains.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Decomposers or Saprophytes > p. 31
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 29: Environment Issues and Health Effects > 29.3.4. Greeenwashing > p. 421
🔗 Anchor: "Are jellyfish detritivores (organisms that feed on decomposing organic matter)?"
👉 Detritivores (detritus feeders)
💡 The insight
Detritivores are organisms that obtain energy by consuming dead organic matter; examples include earthworms and certain soil arthropods.
High-yield for environment/ecology questions: helps answer items on nutrient recycling, soil health and organisms that drive decomposition. Connects directly to topics on composting, humus formation and soil biota. Enables elimination-style reasoning in MCQs asking which organisms recycle organic matter.
📚 Reading List :
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 1: Ecology > ii) Micro consumers - Saprotrophs (decomposers or osmotrophs) > p. 7
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 12: Major Crops and Cropping Patterns in India > Biotic: Living > p. 106
🔗 Anchor: "Are millipedes detritivores (organisms that feed on decomposing organic matter)?"
The 'Earthworm of the Ocean' is the Sea Cucumber. It is a major marine detritivore often harvested illegally. Expect a question on 'Benthic feeders' or Sea Cucumbers in the context of marine pollution or wildlife crime.
Use the 'Hunter Anatomy' Hack. Jellyfish have cnidocytes (stinging cells) to paralyze live prey. Seahorses have specialized snouts to suck in live zooplankton. Predators cannot be primary detritivores. Eliminate 2 (Jellyfish) and 4 (Seahorses). Options A, B, and D are removed instantly. Answer C is the only remainder.
Link Detritivores to GS-3 Agriculture (Soil Health). The decline of soil detritivores (earthworms, micro-arthropods) due to heavy pesticide use breaks the natural nutrient cycle, forcing dependence on synthetic NPK fertilizers. This is the core argument for Natural/Regenerative Farming.