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Nuptial Gift (animal Behavior)
Formally, a nuptial gift is a material presentation to a recipient by a donor during or in relation to sexual intercourse that is not simply gametes in order to improve the reproductive fitness of the donor. Often, such a gift will improve the fitness of the recipient as well. This definition implies neutral gifts, costly gifts and beneficial gifts regarding the fitness of the recipient. Nuptial gifting is at the intersection of sexual selection, nutritional ecology, and life history theory, creating a link between the three. Edible and inedible nuptial gifts Many nuptial gifts are a source of nutrition for the recipient. In many species of animals, including birds, insects, and spiders, this takes the form of a food item that is transferred from a male to a female just prior to copulation. This is a behavior known as courtship feeding. Inedible tokens may include items such as a fragment of leaf or twig, a seed tuft, or a silk balloon. How gifts are received There are three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Intercourse
Sexual intercourse (also coitus or copulation) is a sexual activity typically involving the insertion of the Erection, erect male Human penis, penis inside the female vagina and followed by Pelvic thrust, thrusting motions for sexual pleasure, sexual reproduction, reproduction, or both.Sexual intercourse most commonly means penile–vaginal penetration for sexual pleasure or sexual reproduction; dictionary sources state that it especially means this, and scholarly sources over the years agree. See, for example; * * * * * * * * This is also known as vaginal intercourse or vaginal sex. Sexual penetration is an instinctive form of sexual behaviour and psychology among humans. Other forms of sexual penetration, penetrative sexual intercourse include anal sex (penetration of the Human anus, anus by the penis), oral sex (penetration of the mouth by the penis or oral penetration of the female genitalia), Fingering (sexual act), fingering (sexual penetration by the fingers) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatophore
A spermatophore, from Ancient Greek σπέρμα (''spérma''), meaning "seed", and -φόρος (''-phóros''), meaning "bearing", or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especially salamanders and arthropods, and transferred in entirety to the female's ovipore during reproduction. Spermatophores may additionally contain nourishment for the female, in which case it is called a nuptial gift, as in the instance of bush crickets. In the case of the toxic moth '' Utetheisa ornatrix'', the spermatophore includes sperm, nutrients, and pyrrolizidine alkaloids which prevent predation because it is poisonous to most organisms. However, in some species such as the Edith's checkerspot butterfly, the "gift" provides little nutrient value. The weight of the spermatophore transferred at mating has little effect on female reproductive output. Arthropods Spermatophores are the norm in arachnid Arachnids are arthro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mate Choice
Mate choice is one of the primary mechanisms under which evolution can occur. It is characterized by a "selective response by animals to particular stimuli" which can be observed as behavior.Bateson, Paul Patrick Gordon. "Mate Choice." Mate Choice, Cambridge University Press, 1985 In other words, before an animal engages with a potential mate, they first evaluate various aspects of that mate which are indicative of quality—such as the resources or phenotypes they have—and evaluate whether or not those particular Phenotypic trait, trait(s) are somehow beneficial to them. The evaluation will then incur a response of some sort. These mechanisms are a part of evolutionary change because they operate in a way that causes the qualities that are desired in a mate to be more frequently passed on to each generation over time. For example, if female peacocks desire mates who have a colourful plumage, then this trait will increase in frequency over time as male peacocks with a colourful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Phenotype
''The Extended Phenotype'' is a 1982 book by the evolutionary biologist Richard Dawkins, in which the author introduced a biological concept of the same name. The book's main idea is that phenotype should not be ''limited'' to biological processes such as protein biosynthesis or tissue growth, but ''extended'' to include all effects that a gene has on its environment, inside or outside the body of the individual organism. Dawkins considers ''The Extended Phenotype'' to be a sequel to ''The Selfish Gene'' (1976) aimed at professional biologists, and as his principal contribution to evolutionary theory. Summary Genes as the unit of selection in evolution The central thesis of ''The Extended Phenotype,'' and of its predecessor by the same author, ''The'' ''Selfish Gene'', is that individual organisms are not the true units of natural selection. Instead, the gene — or the 'active, germ-line replicator' — is the unit upon which the forces of evolutionary selection and adaptat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insects
Insects (from Latin ') are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species. The insect nervous system consists of a brain and a ventral nerve cord. Most insects reproduce by laying eggs. Insects breathe air through a system of paired openings along their sides, connected to small tubes that take air directly to the tissues. The blood therefore does not carry oxygen; it is only partly contained in vessels, and some circulates in an open hemocoel. Insect vision is mainly through their compound eyes, with additional small ocelli. Many insects can hear, using tympanal organs, which may be on the legs or other parts of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lizards
Lizard is the common name used for all squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The grouping is paraphyletic as some lizards are more closely related to snakes than they are to other lizards. Lizards range in size from chameleons and geckos a few centimeters long to the 3-meter-long Komodo dragon. Most lizards are quadrupedal, running with a strong side-to-side motion. Some lineages (known as "legless lizards") have secondarily lost their legs, and have long snake-like bodies. Some lizards, such as the forest-dwelling '' Draco'', are able to glide. They are often territorial, the males fighting off other males and signalling, often with bright colours, to attract mates and to intimidate rivals. Lizards are mainly carnivorous, often being sit-and-wait predators; many smaller species eat insects, while the Komodo eats ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birds
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a four-chambered heart, and a strong yet lightweight Bird skeleton, skeleton. Birds live worldwide and range in size from the bee hummingbird to the common ostrich. There are over 11,000 living species and they are split into 44 Order (biology), orders. More than half are passerine or "perching" birds. Birds have Bird wing, wings whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the Flightless bird, loss of flight in some birds, including ratites, penguins, and diverse endemism, endemic island species. The digestive and respiratory systems of birds are also uniquely a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodents
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/ricochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. Once included with rodents, rabbits, hares, and p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Grey Shrike
The great grey shrike (''Lanius excubitor'') is a large and predatory songbird species in the shrike family (biology), family (Laniidae). It forms a superspecies with its parapatric southern relatives, the Iberian grey shrike (''L. meridionalis''), the Chinese grey shrike (''L. sphenocerus'') and the American loggerhead shrike (''L. ludovicianus''). Males and females are similar in plumage, pearly grey above with a black eye-mask and white underparts. Breeding takes place generally north of 50° northern latitude in northern Europe and Fauna of Asia, Asia. Most populations bird migration, migrate south in winter to temperate regions.Harris & Franklin (2000): pp. 152–153 The great grey shrike is carnivorous, with rodents making up over half its diet. Taxonomy and systematics The species was first Species description, scientifically described by Carl Linnaeus in his 1758 edition of ''Systema Naturae'' under the current binomial name. His description is – "a shrike with a wedg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phoreticovelia Disparata
''Phoreticovelia disparata'', also called the Zeus bug, is a species of semi-aquatic bug from the family Veliidae (tribe Microveliini) with a unique form of sexual dimorphism. It is endemic to Australia (Queensland).Polhemus, D. A. & Polhemus, J. T. (2000)Additional new genera and species of Microveliinae (Heteroptera: Veliidae) from New Guinea and adjacent regions.nbsp;— Tijdschrift voor Entomologie 143, 91-123 (2000). Biology ''Phoreticovelia disparata'' live near tropical rivers. They are 1–2 mm in length. It is the only known species (aside from its sister species '' Phoreticovelia rotunda'') where the female feeds the male a nuptial gift. They are sexually dimorphic; the female mating form has a special glandular area on the dorsal surface of the body. The half-sized male (about 1 mm long) clings to her, feeding on the secretions of a pair of glands, sitting on his partner for several days. Both adult males and females have wings, but females are wingless at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pisaura Mirabilis
The nursery web spider ''Pisaura mirabilis'' is a spider species of the family Pisauridae. Description Striking characteristics of ''Pisaura mirabilis'' are its long legs (the fourth pair being the longest) and its slender abdomen ( opisthosoma). The male is between 10 and 13 mm, while the female is 12 to 15 mm. After final ecdysis, the male spiders weigh on average 54 mg and females 68 mg. The prosoma ( cephalothorax) is variable in color, ranging from light to reddish brown and from gray to black. A lighter stripe is visible down the middle of the prosoma. The opisthosoma (abdomen) is long and narrow and tapered towards the rear end. The female spiders has a dark patch ( epigyne) on the underside of her abdomen that includes the copulatory organs. Male genital openings can be found at the same location, but remain inconspicuous. Patterning and coloration varies due to polymorphism. These patterns, which can be caused by hair and pigments, change wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spider
Spiders (order (biology), order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude spider silk, silk. They are the largest order of arachnids and rank seventh in total species diversity among all Order (biology), orders of organisms. Spiders are found worldwide on every continent except Antarctica, and have become established in nearly every land habitat. , 53,034 spider species in 136 Family (biology), families have been recorded by Taxonomy (biology), taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900. Anatomy, Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual body segmentation (biology), segments are fused into two Tagma (biology), tagmata, the cephalothorax or prosoma, and the opisthosoma, or abdomen, and joined by a small, cylindr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
