List of feeding behaviours

Circular dendrogram of feeding behaviours
A mosquito drinking blood (hematophagy) from a human (note the droplet of plasma being expelled as a waste)
A rosy boa eating a mouse whole
A red kangaroo eating grass
The robberfly is an insectivore, shown here having grabbed a leaf beetle
An American robin eating a worm
Hummingbirds primarily drink nectar
A krill filter feeding
A Myrmicaria brunnea feeding on sugar crystals

Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffixes -vore, -vory, or -vorous from Latin vorare, meaning "to devour", or -phage, -phagy, or -phagous from Greek φαγεῖν (phagein), meaning "to eat".

Evolutionary history

The evolution of feeding is varied with some feeding strategies evolving several times in independent lineages. In terrestrial vertebrates, the earliest forms were large amphibious piscivores 400 million years ago. While amphibians continued to feed on fish and later insects, reptiles began exploring two new food types, other tetrapods (carnivory), and later, plants (herbivory). Carnivory was a natural transition from insectivory for medium and large tetrapods, requiring minimal adaptation (in contrast, a complex set of adaptations was necessary for feeding on highly fibrous plant materials).

Classification

By mode of ingestion

Modes of feeding include:

  • Filter feeding: a form of food procurement in which food particles or small organisms are randomly strained from water
  • Deposit feeding: obtaining nutrients from particles suspended in soil
  • Fluid feeding: obtaining nutrients by consuming other organisms' fluids
  • Predation: obtaining nutrients by eating all of an organism
  • Ram feeding and suction feeding: ingesting prey via the fluids around it

By mode of digestion

  • Extra-cellular digestion: excreting digesting enzymes and then reabsorbing the products
  • Myzocytosis: one cell pierces another using a feeding tube, and sucks out cytoplasm
  • Phagocytosis: engulfing food matter into living cells, where it is digested

By food type

Polyphagy is the habit in an animal species, of eating and tolerating a relatively wide variety of foods, whereas monophagy is the intolerance of every food except for one specific type (see generalist and specialist species). Oligophagy is a term for intermediate degrees of selectivity, referring to animals that eat a relatively small range of foods, either because of preference or necessity.

Another classification refers to the specific food animals specialize in eating, such as:

The eating of non-living or decaying matter:

There are also several unusual feeding behaviours, either normal, opportunistic, or pathological, such as:

An opportunistic feeder sustains itself from a number of different food sources, because the species is behaviourally sufficiently flexible.

Storage behaviours

Some animals exhibit hoarding and caching behaviours in which they store or hide food for later use.

See also

References

  1. ↑ Sahney, S., Benton, M.J. & Falcon-Lang, H.J. (2010). "Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica" (PDF). Geology. 38 (12): 1079–1082. doi:10.1130/G31182.1.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ↑ Johns, Timothy A. (1990). With Bitter Herbs They Shall Eat It: Chemical Ecology and the Origins of Human Diet and Medicine. Tucson: University of Arizona Press. p. 5. ISBN 0-8165-1023-7.
  3. ↑ "Detritivore (in Biology Dictionary)". Biology Dictionary. 2019. Archived from the original on July 13, 2025. Retrieved August 21, 2025.
  4. ↑ Park, C; Allaby, M (2017). Necrophage (in A Dictionary of Environment and Conservation) (3rd ed.). Oxford: Oxford University Press. p. 288. ISBN 9780191826320.
  5. ↑ "Scavenger (in Merriam-Webster Dictionary)". Springfield: Merriam-Webster. 2025. Retrieved August 13, 2025. See also: "Scavenger (in National Geographic)". Washington DC: National Geographic Society. 2025. Retrieved August 13, 2025.