Oophagy ( ) or ovophagy, literally "egg eating", is the practice of

embryos An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

feeding on eggs produced by the

ovary The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/ oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are end ...

while still inside the mother's

uterus The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the hollow organ, organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic development, embryonic and prenatal development, f ...

. The word oophagy is formed from the

classical Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archa ...

(, "egg") and classical Greek (, "to eat"). In contrast,

adelphophagy Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecology, ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well ...

is the cannibalism of a multi-celled embryo. Oophagy is thought to occur in all

shark Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...

s in the order

Lamniformes The Lamniformes (, from Greek ''lamna'' "fish of prey") are an order (biology), order of sharks commonly known as mackerel sharks (which may also refer specifically to the family Lamnidae). It includes some of the most familiar species of sharks, ...

and has been recorded in the

bigeye thresher The bigeye thresher (''Alopias superciliosus'') is a species of thresher shark, family Thresher shark, Alopiidae, found in temperate and tropical oceans worldwide. Like the other thresher sharks, nearly half its total length consists of the elong ...

(''Alopias superciliosus''), the

pelagic thresher The pelagic thresher (''Alopias pelagicus'') is a species of thresher shark, family Alopiidae; this group of sharks is characterized by the greatly elongated upper lobes of their caudal fins. The pelagic thresher occurs in the tropical and subt ...

(''A. pelagicus''), the shortfin mako (''Isurus oxyrinchus'') and the

porbeagle The porbeagle or porbeagle shark (''Lamna nasus'') is a species of mackerel shark in the family Lamnidae, distributed widely in the cold and temperate marine waters of the North Atlantic and Southern Hemisphere. In the North Pacific, its ecolo ...

(''Lamna nasus'') among others. It also occurs in the

tawny nurse shark The tawny nurse shark (''Nebrius ferrugineus'') is a species of carpet shark in the family Ginglymostomatidae, and the only extant member of the genus '' Nebrius''. It is found widely along coastlines in the Indo-Pacific, preferring reefs, sa ...

(''Nebrius ferrugineus''), and in the family

Pseudotriakidae The Pseudotriakidae are a small family of ground sharks, belonging to the order Carcharhiniformes, containing the false catsharks (genera '' Pseudotriakis'' and ''Planonasus'') and gollumsharks (genus ''Gollum''). It contains the only ground sh ...

. This practice may lead to larger embryos or prepare the embryo for a predatory lifestyle. There are variations in the extent of oophagy among the different shark species. The

grey nurse shark The sand tiger shark (''Carcharias taurus''), grey/gray nurse shark (in Australia), spotted ragged-tooth shark (in South Africa), or blue-nurse sand tiger, is a species of shark that inhabits subtropical and temperate waters worldwide. It inhabit ...

(''Carcharias taurus'') practices intrauterine cannibalism, the first developed embryo consuming both additional eggs and any other developing embryos.

Slender smooth-hound The slender smooth-hound or gollumshark (''Gollum attenuatus'') is a species of ground shark in the family Pseudotriakidae. It is endemic to the waters around New Zealand, where it is usually found close to the bottom over the continental slop ...

s (''Gollum attenuatus''), form egg capsules which contain 30-80 ova, within which only one ovum develops; the remaining ova are ingested and their yolks stored in its external yolk sac. The embryo then proceeds to develop normally, without ingesting further eggs. Oophagy is used as a synonym of the

egg predation Egg predation or ovivory is a feeding strategy in many groups of animals (ovivores) in which they consume eggs. Since a fertilized egg represents a complete organism at one stage of its Biological life cycle, life cycle, eating an egg is a form ...

practised by some snakes and other animals. Oophagy is used to describe the destruction of non-queen eggs in nests of

eusocial insect Eusociality (Ancient Greek, Greek 'good' and social) is the highest level of organization of sociality. It is defined by the following characteristics: cooperative Offspring, brood care (including care of offspring from other individuals), ove ...

s, especially the

social wasp A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. T ...

s, bees, and ants. This is seen in the wasp species ''

Polistes biglumis ''Polistes biglumis'' is a species of social wasp within ''Polistes'', the most common genus of paper wasp. It is distinguished mainly by its tendency to reside in montane climates in meadows or alpine areas. Selection pressure from the wasp's en ...

'' and ''

Polistes humilis ''Polistes humilis'', known as the Australian paper wasp, is a species of wasp in the family Vespidae that is found throughout Australia and which has been introduced to northern New Zealand. These paper wasps can be identified by their long thin ...

''. Oophagy has been observed in the ant ''

Leptothorax acervorum ''Leptothorax acervorum'' is a small brown to yellow ant in the subfamily Myrmicinae. It was first described by Johan Christian Fabricius in 1793. ''L. acervorum'' is vastly distributed across the globe, most commonly found in the coniferous fore ...

'' and the wasp ''

Parachartergus fraternus ''Parachartergus fraternus'' is a neotropical, swarm founding, Polistinae, polistine wasp species that is distributed throughout Central and South America.Leonardo, Paula C., Flavio R. Andrade, and Fabio Prezoto. "Foraging Behavior in the Neotrop ...

'', where oophagy is practiced to increase energy circulation and provide more dietary protein. The social wasp ''

Polistes fuscatus ''Polistes fuscatus'', whose common name is the dark or northern paper wasp, is widely found in eastern North America, from southern Canada through the southern United States. It often nests around human development. However, it greatly prefers a ...

'' use oophagy as a method to establish a

dominance hierarchy In the zoological field of ethology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social animal, social groups interact, creating a ranking system. Dif ...

; dominant females eat the eggs of subordinate females such that they no longer produce eggs, possibly due to the unnecessary expenditure of energy and resources.West-Eberhard, M. J. 1969 "The social biology of polistine wasps". Mis . Publ. Zool. Univ. Michigan 140, 1-101 This behavior has also been observed in some bee species. Such bee species include ''

Xylocopa sulcatipes ''Xylocopa sulcatipes'' is a large Arabian carpenter bee. These multivoltine bees take part in social nesting and cooperative nesting. They are metasocial carpenter bees that nest in thin dead branches. One or more cooperating females build many ...

'' and ''

Bombus ruderatus ''Bombus ruderatus'', the large garden bumblebee or ruderal bumblebee, is a species of long-tongued bumblebee found in Europe and in some parts of northern Africa. This species is the largest bumblebee in Britain and it uses its long face and to ...

'', where queen bees will eat larvae deposited by workers or eject them from the nest in order to maintain dominance over the colony.

References

{{Cannibalism Sharks Carnivory Biology terminology

See also

References