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Mating Systems
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to animals, the term describes which males and females mate under which circumstances. Recognised systems include monogamy, polygamy (which includes polygyny, polyandry, and polygynandry), and promiscuity, all of which lead to different mate choice outcomes and thus these systems affect how sexual selection works in the species which practice them. In plants, the term refers to the degree and circumstances of outcrossing. In human sociobiology, the terms have been extended to encompass the formation of relationships such as marriage. In plants The primary mating systems in plants are outcrossing (cross-fertilisation), autogamy (self-fertilisation) and apomixis (asexual reproduction without fertilization, but only when arising by modification of sexual function). Mixed mating systems, in which plants use two or even all three mating s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animals
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinoderm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effective Selfing Model
The effective selfing model is a mathematical model that describes the mating system of a plant population in terms of the degree of self-fertilisation present. Overview It was developed in the 1980s by Kermit Ritland, as an alternative to the simplistic mixed mating model. The mixed mating model assumes that every fertilisation event may be classed as either self-fertilisation, or outcrossing with a completely random mate. That is, it assumes that inbreeding is caused solely by self-fertilisation. This assumption is often violated in wild plant populations, where inbreeding may be due to outcrossing between closely related plants. For example, in dense stands, mating often occurs between plants in close proximity; and in plants with short seed dispersal In Spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygynandry
Polygynandry is a mating system in which both males and females have multiple mating partners during a breeding season. In sexually reproducing diploid animals, different mating strategies are employed by males and females, because the cost of gamete production is lower for males than it is for females. The different mating tactics employed by males and females are thought to be the outcome of stochastic reproductive conflicts both ecologically and socially. Reproductive conflicts in animal societies may arise because individuals are not genetically identical and have different optimal strategies for maximizing their fitness; and often it is found that reproductive conflicts generally arise due to dominance hierarchy in which all or a major part of reproduction is monopolized by only one individual. In the wasp ''Polistes carolina'', the dominant queen amongst female wasps is determined by whoever arrives at the nest first rather than the largest foundress, who is expected to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Honey Bee
The western honey bee or European honey bee (''Apis mellifera'') is the most common of the 7–12 species of honey bees worldwide. The genus name ''Apis'' is Latin for "bee", and ''mellifera'' is the Latin for "honey-bearing" or "honey carrying", referring to the species' production of honey. Like all honey bee species, the western honey bee is eusocial, creating colonies with a single fertile female (or "queen"), many normally non-reproductive females or "workers", and a small proportion of fertile males or " drones". Individual colonies can house tens of thousands of bees. Colony activities are organized by complex communication between individuals, through both pheromones and the dance language. The western honey bee was one of the first domesticated insects, and it is the primary species maintained by beekeepers to this day for both its honey production and pollination activities. With human assistance, the western honey bee now occupies every continent except Antarctic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyandry In Nature
In behavioral ecology, polyandry is a class of mating system where one female mates with several males in a breeding season. Polyandry is often compared to the polygyny system based on the cost and benefits incurred by members of each sex. Polygyny is where one male mates with several females in a breeding season (e.g., lions, deer, some primates, and many systems where there is an alpha male). A common example of polyandrous mating can be found in the field cricket (''Gryllus bimaculatus'') of the invertebrate order Orthoptera (containing crickets, grasshoppers, and groundhoppers). Polyandrous behavior is also prominent in many other insect species, including the red flour beetle and the species of spider '' Stegodyphus lineatus''. Polyandry also occurs in some primates such as marmosets, mammal groups, the marsupial genus' '' Antechinus'' and bandicoots, around 1% of all bird species, such as jacanas and dunnocks, insects such as honeybees, and fish such as pipefish. Predicto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylocopa Micans
''Xylocopa micans'', also known as the southern carpenter bee, is a species of bee within '' Xylocopa'', the genus of carpenter bees. The southern carpenter bee can be found mainly in the coastal and gulf regions of the southeastern United States, as well as Mexico and Guatemala. Like all ''Xylocopa'' bees, ''X. micans'' bees excavate nests in woody plant material. However, unlike its sympatric species '' Xylocopa virginica'', ''X. micans'' has not been found to construct nest galleries in structural timbers of building, making it less of an economic nuisance to humans. Carpenter bees have a wide range of mating strategies between different species. The southern carpenter bee exhibits a polymorphic mating strategy, with its preferred method of mating changing as the season progresses from early spring to mid summer. Like most bees in its genus, the southern carpenter bee is considered a solitary bee because it does not live in colonies. Taxonomy and phylogeny The French e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grayling (butterfly)
The grayling or rock grayling (''Hipparchia semele'') is a species in the brush-footed butterfly family Nymphalidae. Although found all over Europe, the grayling mostly inhabits coastal areas, with inland populations declining significantly in recent years. The grayling lives in dry and warm habitats with easy access to the sun, which helps them with body temperature regulation. A grayling goes through four stages in its life cycle. The eggs hatch around August, and larvae grow in four instars from August to the following June. By June, the larvae begin to pupate by spinning a silk cocoon below the surface of the ground. The adult grayling emerges around August. The grayling migrates in small groups of two or three butterflies throughout most of August, typically moving southeast. ''H. semele'' engages in cryptic coloring, with their tan and brown colored wings helping them camouflage into their surroundings. The grayling exposes the eyespots on its wings when it believes to hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vespula Squamosa
''Vespula squamosa'', the southern yellowjacket, is a social wasp. This species can be identified by its distinctive black and yellow patterning and orange queen. These yellowjackets are typically found in eastern North America, and its territory extends as far south as Central America. Within these territories, they create enormous, multiple-comb nests.MacDonald, John F., Matthews, R. W. "Nesting Biology of the Southern Yellowjacket, ''Vespula squamosa'' (Hymenoptera: Vespidae): Social Parasitism and Independent Founding", "Journal of the Kansas Entomological Society", January 1984. The colonies may be either annual or perennial depending on the climate, and in many perennial nests, polygyny takes place. In addition, this species uses pheromones both as a sexual attractant and an alarm signal.Landoldt, P. J. and Heath, R. R. "Alarm Pheromone Behavior of Vespula Squamosa (Hymenoptera: Vespidae)", "Florida Entomologist". June 1987. This species feeds on insects and animal carcass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrates
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with currently about 69,963 species described. Vertebrates comprise such groups as the following: * jawless fish, which include hagfish and lampreys * jawed vertebrates, which include: ** cartilaginous fish (sharks, rays, and ratfish) ** bony vertebrates, which include: *** ray-fins (the majority of living bony fish) *** lobe-fins, which include: **** coelacanths and lungfish **** tetrapods (limbed vertebrates) Extant vertebrates range in size from the frog species ''Paedophryne amauensis'', at as little as , to the blue whale, at up to . Vertebrates make up less than five percent of all described animal species; the rest are invertebrates, which lack vertebral columns. The vertebrates traditionally include the hagfish, which do not have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygyny In Nature
Polygyny (; from Ancient Greek#Modern use, Neo-Greek πολυγυνία, from Wiktionary:πολύς, πολύ- ''poly-'', "many", and Wiktionary:γυνή, γυνή ''gyne'', "woman" or "wife") is a mating system in which one male lives and mates with multiple females but each female only mates with a single male. Systems where several females mate with several males are defined either as Animal sexual behaviour#Promiscuity, promiscuity or polygynandry. Lek mating is frequently regarded as a form of polygyny, because one male mates with many females, but lek-based mating systems differ in that the male has no attachment to the females with whom he mates, and that mating females lack attachment to one another.Clutton-Brock T.H. (1989). ‘Review lecture: mammalian mating systems.' ''Proceedings of the Royal Society of London''. Series B, Biological Sciences 236: 339–372. Polygyny is typical of one-male, multi-female groupsBoyd, R., & Silk, J. B. (2009). How Humans Evolved (preferably ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygamy
Crimes Polygamy (from Late Greek (') "state of marriage to many spouses") is the practice of marriage, marrying multiple spouses. When a man is married to more than one wife at the same time, sociologists call this polygyny. When a woman is married to more than one husband at a time, it is called polyandry. In contrast to polygamy, monogamy is marriage consisting of only two parties. Like "monogamy", the term "polygamy" is often used in a ''de facto'' sense, applied regardless of whether a State (polity), state recognizes the relationship.For the extent to which states can and do recognize potentially and actual polygamous forms as valid, see Conflict of marriage laws. In sociobiology and zoology, researchers use ''polygamy'' in a broad sense to mean any form of multiple mating. Worldwide, different societies variously encourage, accept or outlaw polygamy. In societies which allow or tolerate polygamy, in the vast majority of cases the form accepted is polygyny. According t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pair Bond
In biology, a pair bond is the strong affinity that develops in some species between a mating pair, often leading to the production and rearing of offspring and potentially a lifelong bond. Pair-bonding is a term coined in the 1940s that is frequently used in sociobiology and evolutionary biology circles. The term often implies either a lifelong socially monogamous relationship or a stage of mating interaction in socially monogamous species. It is sometimes used in reference to human relationships. Varieties According to evolutionary psychologists David P. Barash and Judith Lipton, from their 2001 book ''The Myth of Monogamy'', there are several varieties of pair bonds: *''Short-term pair-bond:'' a transient mating or associations *''Long-term pair-bond:'' bonded for a significant portion of the life cycle of that pair *''Lifelong pair-bond:'' mated for life *''Social pair-bond:'' attachments for territorial or social reasons *''Clandestine pair-bond:'' quick extra-pair copulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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