Corynopoma | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Characiformes |
Family: | Characidae |
Genus: | Corynopoma T. N. Gill, 1858 |
Species: | C. riisei |
Binomial name | |
Corynopoma riisei T. N. Gill, 1858 | |
Corynopoma riisei, also known as the sword-tail characin, is a species of characin found in Colombia, Trinidad and Tobago and Venezuela. [1] It is also kept as an aquarium fish. This species is the only member of the genus Corynopoma. [2]
Corynopoma riisei have pronounced sexual dimorphism, the females being more aggressive and dominant than males. [3] [4] Males have a grey-black, flag-like ornament that extends from the operculum on each side of the body. [3] [4] This flag is normally held close to the body, but when trying to mate a male will extend the ornament and wave it in front of a female. [5] [3] [4] During courtship the flag is displayed by the males one at a time and at a right angle from its body, they will perform both ornament displays and zigzags. [4] Courtship may extend over several days in swordtail characin. [4]
The flag-like ornament is used as a food mimic to attract females. [3] [4] The females will try to bite at the ornament, which is then often damaged during courtship and can possibly take up to weeks to regenerate. [5] [3] Studies have shown that unfed females will respond more to the male ornament and show a preference for the larger flags than those that had been fed. [5]
This is an example of sensory exploitation because the males are exploiting the females' pre-existing bias to seem more attractive and have more opportunities to mate. [5] Males lack external gonopodia so in order for internal fertilization to occur in the female, they need to be within close proximity for the sperm to transfer successfully. [4] [5] The males use this food mimic to get them within close proximity of females, and will show different ornament displays based on the attractiveness of their ornaments. [3] Males that do not show an overall large ornament size or symmetry can compensate by displaying or zigzagging their flags more often. [4] The males may also be using the hooks on the anal fin to direct the sperm for transfer. [6]
Females store viable sperm internally for up to ten months and will mate with multiple different males in their lifetime. [7] These females would be receiving indirect benefits for the offspring as they are not directly choosing which males they want to be inseminated by but are selecting a food-mimic which can be related to male attractiveness. This attractive quality could then be passed on to offspring.
This species could also be used as an example of sensory drive, males are shown to have morphological differences based on their location and prey available, the females prefer the males whose flag ornament best resembles prey items of the population they live in. [3] [8] It has been demonstrated that the flag resembles an ant, because that is the most common natural prey of the swordtail characin. [3] This plasticity in mate choice can also been shown in a laboratory setting when food colour was altered the females also changed the preference for males to have a flag that matches the colour of food. [3]
Recently it has been hypothesized that the males caudal pheromone gland is used to release pheromones that decrease stress in females and increase activity. [7] This could potentially aid the males in gaining access to females and facilitating the sperm transfer. [7]
A seahorse is any of 46 species of small marine fish in the genus Hippocampus. "Hippocampus" comes from the Ancient Greek hippókampos (ἱππόκαμπος), itself from híppos (ἵππος) meaning "horse" and kámpos (κάμπος) meaning "sea monster" or "sea animal". Having a head and neck suggestive of a horse, seahorses also feature segmented bony armour, an upright posture and a curled prehensile tail. Along with the pipefishes and seadragons they form the family Syngnathidae.
Behavioral ecology, also spelled behavioural ecology, is the study of the evolutionary basis for animal behavior due to ecological pressures. Behavioral ecology emerged from ethology after Niko Tinbergen outlined four questions to address when studying animal behaviors: What are the proximate causes, ontogeny, survival value, and phylogeny of a behavior?
The bowl and doily spider is a species of sheet weaver found in North and Central America. It is a small spider, about 4 mm (0.16 in) long, that weaves a fairly complex and unique sheet web system consisting of an inverted dome shaped web, or "bowl," suspended above a horizontal sheet web, or "doily", hence its common name. The spider hangs from the underside of the "bowl", and bites through the web small flies, gnats and other small insects that fall down into the non-sticky webbing. The webs are commonly seen in weedy fields and in shrubs, and may often contain both a male and a female spider in late summer—like many linyphiids, Frontinella males and females may cohabitate for some time. Males exhibit competition for female mates both by fighting and sperm competition. Uniquely, these spiders exhibit behavioral thermoregulation and have lengthened circadian rhythms.
Sperm competition is the competitive process between spermatozoa of two or more different males to fertilize the same egg during sexual reproduction. Competition can occur when females have multiple potential mating partners. Greater choice and variety of mates increases a female's chance to produce more viable offspring. However, multiple mates for a female means each individual male has decreased chances of producing offspring. Sperm competition is an evolutionary pressure on males, and has led to the development of adaptations to increase male's chance of reproductive success. Sperm competition results in a sexual conflict between males and females. Males have evolved several defensive tactics including: mate-guarding, mating plugs, and releasing toxic seminal substances to reduce female re-mating tendencies to cope with sperm competition. Offensive tactics of sperm competition involve direct interference by one male on the reproductive success of another male, for instance by physically removing another male's sperm prior to mating with a female. For an example, see Gryllus bimaculatus.
Teleogryllus oceanicus, commonly known as the Australian, Pacific or oceanic field cricket, is a cricket found across Oceania and in coastal Australia from Carnarvon in Western Australia and Rockhampton in north-east Queensland
Sexual cannibalism is when an animal, usually the female, cannibalizes its mate prior to, during, or after copulation. It is a trait observed in many arachnid orders and several insect orders. Several hypotheses to explain this seemingly paradoxical behavior have been proposed. The adaptive foraging hypothesis, aggressive spillover hypothesis and mistaken identity hypothesis are among the proposed hypotheses to explain how sexual cannibalism evolved. This behavior is believed to have evolved as a manifestation of sexual conflict, occurring when the reproductive interests of males and females differ. In many species that exhibit sexual cannibalism, the female consumes the male upon detection. Females of cannibalistic species are generally hostile and unwilling to mate; thus many males of these species have developed adaptive behaviors to counteract female aggression.
Glandulocaudinae are a subfamily of tropical freshwater characin fish from Central and South America. In all species of this subfamily, a gland on their caudal fin is found almost exclusively in the males, which allows the release and pumping of pheromones; also, members of this subfamily have complex courtship behaviors which lead to insemination. The ecology and life history of these fish is complex yet little studied. Glandulocaudines are important as food fish for larger fish important for commercial and subsistence reasons.
Sex pheromones are pheromones released by an organism to attract an individual of the same species, encourage them to mate with them, or perform some other function closely related with sexual reproduction. Sex pheromones specifically focus on indicating females for breeding, attracting the opposite sex, and conveying information on species, age, sex and genotype. Non-volatile pheromones, or cuticular contact pheromones, are more closely related to social insects as they are usually detected by direct contact with chemoreceptors on the antennae or feet of insects.
A courtship display is a set of display behaviors in which an animal, usually a male, attempts to attract a mate; the mate exercises choice, so sexual selection acts on the display. These behaviors often include ritualized movement ("dances"), vocalizations, mechanical sound production, or displays of beauty, strength, or agonistic ability.
Utetheisa ornatrix, also called the ornate bella moth, ornate moth, bella moth or rattlebox moth is a moth of the subfamily Arctiinae. It is aposematically colored ranging from pink, red, orange and yellow to white coloration with black markings arranged in varying patterns on its wings. It has a wingspan of 33–46 mm. Moths reside in temperate midwestern and eastern North America as well as throughout Mexico and other parts of Central America. Unlike most moths, the bella moth is diurnal. Formerly, the bella moth or beautiful utetheisa of temperate eastern North America was separated as Utetheisa bella. Now it is united with the bella moth in Utetheisa ornatrix.
A biological ornament is a characteristic of an animal that appears to serve a decorative function rather than a utilitarian function. Many are secondary sexual characteristics, and others appear on young birds during the period when they are dependent on being fed by their parents. Ornaments are used in displays to attract mates, which may lead to the evolutionary process known as sexual selection. An animal may shake, lengthen, or spread out its ornament in order to get the attention of the opposite sex, which will in turn choose the most attractive one with which to mate. Ornaments are most often observed in males, and choosing an extravagantly ornamented male benefits females as the genes that produce the ornament will be passed on to her offspring, increasing their own reproductive fitness. As Ronald Fisher noted, the male offspring will inherit the ornament while the female offspring will inherit the preference for said ornament, which can lead to a positive feedback loop known as a Fisherian runaway. These structures serve as cues to animal sexual behaviour, that is, they are sensory signals that affect mating responses. Therefore, ornamental traits are often selected by mate choice.
A nuptial gift is a nutritional gift given by one partner in some animals' sexual reproduction practices.
Sexual selection in birds concerns how birds have evolved a variety of mating behaviors, with the peacock tail being perhaps the most famous example of sexual selection and the Fisherian runaway. Commonly occurring sexual dimorphisms such as size and color differences are energetically costly attributes that signal competitive breeding situations. Many types of avian sexual selection have been identified; intersexual selection, also known as female choice; and intrasexual competition, where individuals of the more abundant sex compete with each other for the privilege to mate. Sexually selected traits often evolve to become more pronounced in competitive breeding situations until the trait begins to limit the individual's fitness. Conflicts between an individual fitness and signaling adaptations ensure that sexually selected ornaments such as plumage coloration and courtship behavior are “honest” traits. Signals must be costly to ensure that only good-quality individuals can present these exaggerated sexual ornaments and behaviors.
Sexual selection in amphibians involves sexual selection processes in amphibians, including frogs, salamanders and newts. Prolonged breeders, the majority of frog species, have breeding seasons at regular intervals where male-male competition occurs with males arriving at the waters edge first in large number and producing a wide range of vocalizations, with variations in depth of calls the speed of calls and other complex behaviours to attract mates. The fittest males will have the deepest croaks and the best territories, with females making their mate choices at least partly based on the males depth of croaking. This has led to sexual dimorphism, with females being larger than males in 90% of species, males in 10% and males fighting for groups of females.
Ostrinia furnacalis is a species of moth in the family Crambidae, the grass moths. It was described by Achille Guenée in 1854 and is known by the common name Asian corn borer since this species is found in Asia and feeds mainly on corn crop. The moth is found from China to Australia, including in Java, Sulawesi, the Philippines, Borneo, New Guinea, the Solomon Islands, and Micronesia. The Asian corn borer is part of the species complex, Ostrinia, in which members are difficult to distinguish based on appearance. Other Ostrinia such as O. orientalis, O. scapulalis, O. zealis, and O. zaguliaevi can occur with O. furnacalis, and the taxa can be hard to tell apart.
Neumania papillator is a water mite in the genus Neumania and is known in behavioural ecology as an example of sensory exploitation - males of this species hijack existing female sensory abilities for their own gain in courtship.
In zoology, copulation is animal sexual behavior in which a male introduces sperm into the female's body, especially directly into her reproductive tract. This is an aspect of mating. Many animals that live in water use external fertilization, whereas internal fertilization may have developed from a need to maintain gametes in a liquid medium in the Late Ordovician epoch. Internal fertilization with many vertebrates occurs via cloacal copulation, known as cloacal kiss, while mammals copulate vaginally, and many basal vertebrates reproduce sexually with external fertilization.
Rhamphomyia longicauda, the long-tailed dance fly, is a species of fly commonly found in eastern North America that belongs to the family Empididae and part of the superfamily of dance flies Empidoidea. It is included in the subgenus Rhamphomyia. This species of fly is most known for sex role reversal during courtship, as females put on exaggerated displays and congregate in leks to attract males. Females cannot hunt for food, so they receive protein from nuptial gifts brought to them by males. Female dependence on males for nutrition is the principal cause for sex role reversal in this species of fly.
The sensory trap hypothesis describes an evolutionary idea that revolves around mating behavior and female mate choice. It is a model of female preference and male sexual trait evolution through what is known as sensory exploitation. Sensory exploitation, or a sensory trap is an event that occurs in nature where male members of a species perform behaviors or display visual traits that resemble a non-sexual stimulus which females are responsive to. This tricks females into engaging with the males, thus creating more mating opportunities for males. What makes it a sensory trap is that these female responses evolved in a non-sexual context, and the male produced stimulus exploits the female response which would not otherwise occur without the mimicked stimulus.
The red-sided garter snake is a subspecies of the common garter snake, in the subfamily Natricinae of the family Colubridae. This slender subspecies of natricine snake is indigenous to North America and is one of the recognized subspecies of Thamnophis sirtalis. This subspecies is widely spread across northern United States and southern Canada.