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Oophagy
Oophagy ( ) sometimes 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 consuming ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Microsate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, sandy flats, and seagrass beds from very shallow water to a depth of . With a cylindrical body and a broad, flattened head, the tawny nurse shark is quite similar in appearance to the nurse shark (''Ginglymostoma cirratum'') of the Atlantic and East Pacific, from which it can be distinguished by its pointed-tipped dorsal fins and narrow, sickle-shaped pectoral fins. The maximum recorded length of the tawny nurse shark is . Nocturnal in habits, the tawny nurse shark tends to spend the day resting in piles of two dozen or more individuals inside caves or under ledges. At night, it is an active-swimming predator that uses a powerful suction force to extract prey from inside holes and crevices. The diet of this species consists mainly of octopus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polistes
Wasps of the cosmopolitan genus ''Polistes'' (the only genus in the tribe Polistini) are the most familiar of the polistine wasps, and are the most common type of paper wasp in North America. Walter Ebeling coined the vernacular name "umbrella wasps" for this genus in 1975 to distinguish it from other types of paper wasp, in reference to the form of their nests. It is also the single largest genus within the family Vespidae, with over 300 recognized species and subspecies. Their innate preferences for nest-building sites leads them to commonly build nests on human habitation, where they can be very unwelcome; although generally not aggressive, they can be provoked into defending their nests. All species are predatory, and they may consume large numbers of caterpillars, in which respect they are generally considered beneficial. The European paper wasp, ''Polistes dominula'', was introduced into the US about 1981 and has quickly spread throughout most of the country, in most cases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 slope at depths of . An extremely slim, plain brownish shark reaching in length, the slender smooth-hound can be identified by its broad, flattened head with a long, distinctively bell-shaped snout. Its mouth is angular with short furrows at the corners, and contains a very high number of tooth rows in both jaws. Its two dorsal fins are roughly equal in size. The diet of the slender smooth-hound is diverse, but dominated by small, benthic bony fishes and decapod crustaceans. It exhibits a specialized form of aplacental viviparity with oophagy: the females produce a single capsule in each uterus that contains 30–80 ova, of which one ovum develops into an embryo that consumes the rest of the ova and stores the yolk material in its external y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 mesoscu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bigeye Thresher
The bigeye thresher (''Alopias superciliosus'') is a species of thresher shark, family Alopiidae, found in temperate and tropical oceans worldwide. Like the other thresher sharks, nearly half its total length consists of the elongated upper lobe of the tail fin. Its common name comes from its enormous eyes, which are placed in keyhole-shaped sockets that allow them to be rotated upward. This species can also be distinguished by a pair of deep grooves on the top of its head, from which its scientific name is derived. The large eyes of the bigeye thresher are adapted for hunting in low light conditions. It is one of the few sharks that conduct a diel vertical migration, staying in deep water during the day and moving into surface waters at night to feed. To protect its sensitive brain and eyes from the temperature changes accompanying these movements, the bigeye thresher has a vascular exchange system called the rete mirabile around those organs. This species feeds mainly on fish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 eggs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porbeagle Shark
The porbeagle (''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 ecological equivalent is the closely related salmon shark (''L. ditropis''). It typically reaches in length and a weight of ; North Atlantic sharks grow larger than Southern Hemisphere sharks and differ in coloration and aspects of life history. Gray above and white below, the porbeagle has a very stout midsection that tapers towards the long, pointed snout and the narrow base of the tail. It has large pectoral and first dorsal fins, tiny pelvic, second dorsal, and anal fins, and a crescent-shaped caudal fin. The most distinctive features of this species are its three-cusped teeth, the white blotch at the aft base of its first dorsal fin, and the two pairs of lateral keels on its tail. The porbeagle is an opportunistic hunter that preys mainly on bony fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polistes Humilis
''Polistes humilis'', known as the common paper wasp, is a species of wasp in the Vespidae family that is found throughout Australia and which has been introduced to northern New Zealand. These paper wasps can be identified by their long thin legs and banded yellow and black coloring. They have been known to re-utilize old nests. While the species does not exhibit morphological class differences, there are distinct behavioral differences between queens and workers. In addition, the species is eusocial and benefits from relatedness between individuals. They are known for delivering a painful sting, especially when their nest is disturbed, a behavior that has been developed as a nest defense mechanism. While wasps are often viewed negatively, they play an important pollination role for many plants. Taxonomy and phylogeny ''Polistes humilis'' is in the genus ''Polistes'', which consists of 150 species that can be found in all regions except the world's coldest climates. ''Polistes hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 shark species that exhibit intrauterine oophagy, in which developing fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal deve ...es are nourished by eggs produced by their mother. Undescribed species One undescribed species is known - one in the genus ''Gollum'', (''Gollum'' sp. B) - the white-marked gollumshark.Weigmann, S., Stehmann, M.F.W. & Thiel, R. (2013): ''Planonasus parini'' n. g. and n. sp., a new genus and species of false cat sharks (Carchariniformes, Pseudotriakidae) from the deep northwestern Indian Ocean off Socotra Islands. ''Zoot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shortfin Mako
The shortfin mako shark (; ; ''Isurus oxyrinchus''), also known as the blue pointer or bonito shark, is a large mackerel shark. It is commonly referred to as the mako shark, as is the longfin mako shark (''Isurus paucus''). The shortfin mako can reach a size of in length and weigh . The species is classified as Endangered by the IUCN. Etymology "Mako" comes from the Māori language, meaning either the shark or a shark tooth. Following the Māori language, "mako" in English is both singular and plural. The word may have originated in a dialectal variation, as it is similar to the common words for shark in a number of Polynesian languages—''makō'' in the Kāi Tahu Māori dialect, ''mangō'' in other Māori dialects, "mago" in Samoan, ''ma'o'' in Tahitian, and ''mano'' in Hawaiian. The first written usage is in Lee and Kendall's ''Grammar and vocabulary of the language of New Zealand'' (1820), which simply states, "Máko; A certain fish". Richard Taylor's ''A leaf from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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