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Oophagy
Oophagy ( ) or ovophagy, literally "egg eating", is the practice of embryos feeding on eggs produced by the ovary while still inside the mother's uterus. The word oophagy is formed from the classical Greek (, "egg") and classical Greek (, "to eat"). In contrast, adelphophagy is the cannibalism of a multi-celled embryo. Oophagy is thought to occur in all sharks in the order Lamniformes and has been recorded in the bigeye thresher (''Alopias superciliosus''), the pelagic thresher (''A. pelagicus''), the shortfin mako (''Isurus oxyrinchus'') and the porbeagle (''Lamna nasus'') among others. It also occurs in the tawny nurse shark (''Nebrius ferrugineus''), and in the family Pseudotriakidae. 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 (''Carcharias taurus'') practices intrauterine cannibalism, the first developed embryo consum ...
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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 of predation, the killing of another organism for food. Egg predation is found widely across the animal kingdom, including in fish, birds, snakes, mammals, and arthropods. Some species are specialist egg predators, but many more are generalists which take eggs when the opportunity arises. Humans have accidentally or intentionally introduced egg predators such as Rat, rats to places that had been free of them, causing damage to native species such as ground-nesting seabirds. Predatory birds such as ravens and gulls have spread, threatening ground-nesting birds such as Centrocercus, sage grouse and terns. Measures to control such predators include the use of poisoned bait eggs. Definitions An ovivore or ovivorous animal is one that eats ...
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Cannibalism (zoology)
Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well documented, both in ancient and in recent times. The rate of cannibalism increases in nutritionally poor environments as individuals turn to members of their own species as an additional food source.Elgar, M.A. & Crespi, B.J. (1992) ''Cannibalism: ecology and evolution among diverse taxa'', Oxford University Press, Oxford ngland New York. Cannibalism regulates population numbers, whereby resources such as food, shelter and territory become more readily available with the decrease of potential competition. Although it may benefit the individual, it has been shown that the presence of cannibalism decreases the expected survival rate of the whole population and increases the risk of consuming a relative. Other negative effects may include the increa ...
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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 subtropical waters of the Indian and Pacific Oceans, usually far from shore, but occasionally entering coastal habitats. It is often confused with the common thresher (''A. vulpinus''), even in professional publications, but can be distinguished by the dark, rather than white, color over the bases of its pectoral fins. The smallest of the three thresher species, the pelagic thresher typically measures 3 m (10 ft) long. The diet of the pelagic thresher consists mainly of small midwater fishes, which are stunned with whip-like strikes of its tail. Along with all other mackerel sharks, the pelagic thresher exhibits ovoviviparity and usually gives birth to litters of two. The developing embryos are oophagous, feeding on unfertilized e ...
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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 Neotropical Swarm-founding Wasp Parachartergus Fraternus (Hymenoptera: Vespidae: Polistinae: Epiponini) during Different Phases of the Biological Cycle." ''Sociobiology'' 42 (2003): 735–43. Web. 11 Oct. 2014. They live in nests in second growth tropical dry forests, near pasture fields, roadside areas, and urban areas as well.Olson, Eric J. "Parachartergus Fraternus (Gribodo)(Hymenoptera: Vespidae: Polistinae) Uses Venom When Taking Caterpillar Prey." ''Psyche: A Journal of Entomology'' 103.1–2 (2000): 85–93. Web. 11 Oct. 2014. These wasps eat insects, such as caterpillars of Lepidoptera. They also drink nectar, honeydew (secretion), honeydew, and water.Mateus, Sidnei, Fernando Barbosa Noll, and Ronaldo Zucchi. "Caste Flexibility and Variati ...
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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 forests of Central, Western and Northern Europe. The morphology of ''L. acervorum'' is extremely similar to that of other '' Leptothorax'' ants. The difference arises in the two-toned appearance of ''L. acervorum'', with the head and metasoma being darker than the mesosoma segment of the body, and hair across its body. Following Bergmann's rule—unusually, for ectothermic animals—body size increases with latitude. Taxonomy ''Leptothorax acervorum'' was first described by Johan Christian Fabricius in 1793 in his publication ''Entomologia systematica emendata et aucta. Vol 2''. The ant belongs to the family of Formicidae, which include all organisms that contain a metapleural gland. Using DNA analysis, the divergence date estimated for clades ...
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Isurus Oxyrinchus By Mark Conlin3
''Isurus'' (meaning "equal tail") is a genus of mackerel sharks in the family Lamnidae, commonly known as the mako sharks. They are largely pelagic, and are fast, predatory fish capable of swimming at speeds of up to . Fossil history and evolution Although fossil teeth of ''Isurus'' have been reported from as early as the Late Cretaceous, they are likely to be of a shark with a similar dentition, ''Cretoxyrhina''; since at one point they were considered to be the same (now defunct) genus ''Oxyrhina'', and modern referrals to ''Isurus'' in the Cretaceous are scant. The earliest appearance of ''Isurus'' proper seems to be during the Oligocene with ''Isurus desori''. There has been much debate and speculation about the evolutionary origin and relationships between ''Isurus'' and its closest relatives, including the extant great white shark (''Carcharodon carcharias''). Molecular clock analyses place the last common ancestor of ''Isurus'' and '' Carcharodon'' between 43–60 mill ...
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Sharks
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 Division (taxonomy), division Selachii and are the sister group to the Batoidea, Batomorphi (Batoidea, rays and skate (fish), skates). Some sources extend the term "shark" as an informal category including Extinction, extinct members of Chondrichthyes (cartilaginous fish) with a shark-like morphology, such as hybodonts. Shark-like chondrichthyans such as ''Cladoselache'' and ''Doliodus'' first appeared in the Devonian Period (419–359 million years), though some fossilized chondrichthyan-like scales are as old as the Ordovician, Late Ordovician (458–444 million years ago). The earliest confirmed modern sharks (Selachii) are known from the Early Jurassic around , with the oldest known member being ''Agaleus'', though records of true shar ...
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Siblicide
Siblicide (attributed by behavioural ecologist Doug Mock to Barbara M. Braun) is the killing of an infant individual by its close relatives (full or half siblings). It may occur directly between siblings or be mediated by the parents, and is driven by the direct fitness benefits to the perpetrator and sometimes its parents. Siblicide has mainly, but not only, been observed in birds. (The word is also used as a unifying term for fratricide and sororicide in the human species; unlike these more specific terms, it leaves the sex of the victim unspecified.) Siblicidal behavior can be either obligate or facultative. Obligate siblicide is when a sibling almost always ends up being killed. Facultative siblicide means that siblicide may or may not occur, based on environmental conditions. In birds, obligate siblicidal behavior results in the older chick killing the other chick(s). In facultative siblicidal animals, fighting is frequent, but does not always lead to death of a sibling; ...
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Large Garden Bumblebee
''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 tongue to pollinate hard-to-reach tubed flowers. Bumblebees are key pollinators in many agricultural ecosystems, which has led to ''B. ruderatus'' and other bumblebees being commercially bred and introduced into non-native countries, specifically New Zealand and Chile. Since its introduction in Chile, ''B. ruderatus'' has spread into Argentina as well. Population numbers have been declining and it has been placed on the Biodiversity Action Plan to help counteract these declines. Taxonomy and phylogeny ''Bombus ruderatus'' is part of the order Hymenoptera and the family Apidae. ''B. ruderatus'' is in the genus Bombus and is one of 239 species of bumblebees, with 23 of those existing in Britain alone. ''B. ruderatus'' is part of the subgenu ...
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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 brood cells. They have been extensively studied in Saudi Arabia and Israel. Taxonomy and phylogeny ''X. sulcatipes'' is part of the subfamily Xylocopinae within the hymenopteran family Apidae. Xylocopinae is divided into four tribes: Allodapini, Ceratinini, Xylocopini, and Manueliini. The genus ''Xylocopa'', composed of large carpenter bees, consists of about 469 species in 31–51 subgenera, and the species are found throughout the world. ''X. sulcatipes'' is part of the subgenus ''Ctenoxylocopa''. Description and identification ''X. sulcatipes'' differs from other Arabian carpenter bees. Females are distinguishable by the presence of black pubescence (short matted hairs) on the face and the back side of the mesosoma. The Scutellum ( ...
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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. Different types of interactions can result in dominance depending on the species, including Ritualized aggression, ritualized displays of aggression or direct physical violence. In social living groups, members are likely to compete for access to limited resources and mating opportunities. Rather than fighting each time they meet, individuals of the same sex establish a relative rank, with higher-ranking individuals often gaining more access to resources and mates. Based on repetitive interactions, a social order is created that is subject to change each time a dominant animal is challenged by a subordinate one. Definitions Dominance is an individual's preferential access to resources over another based on coercive capacity based on streng ...
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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 areas in which wood is readily available for use as nest material, therefore they are also found near and in woodlands and savannas.Evans, H. (1963). ''Wasp Farm.'' Ithaca: Cornell University Press. ''P. fuscatus'' is a social wasp that is part of a complex society based around a single dominant foundress along with other cofoundresses and a dominance hierarchy. Taxonomy and phylogeny ''P. fuscatus'' is a part of the order Hymenoptera, the suborder Apocrita, the family of Vespidae, and the subfamily Polistinae, the second-largest subfamily within the Vespidae, of which all are social wasps.Arevalo, Elisabeth, Yong Zhu, James Carpenter, and Joan Strassmann. (2004). The Phylogeny of the Social Wasp Subfamily Polistinae: Evidencefrom Microsat ...
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