Sepsis cynipsea

Last updated

Sepsis cynipsea
Sepsis cynipsea, Marford Quarry, North Wales, June 2011 - Flickr - janetgraham84.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Family: Sepsidae
Subfamily: Sepsinae
Genus: Sepsis
Species:
S. cynipsea
Binomial name
Sepsis cynipsea
Synonyms

Sepsis cynipsea is a European species of fly and member of the family Sepsidae. [1] It is a coprophagous fly that feeds on dung. [2] These flies are most commonly found around freshly laid cattle dung where they eat and reproduce. Due to human agricultural practices involving cows, these flies are now common in other areas of the world. [1]

Contents

Sepsis cynipsea has been studied extensively due to its sexual selection and reproductive practices. They exhibit sexual conflict: males compete for females and mount females to guard them for reproductive purposes. The females have been observed attempting to shake the males off. [3]

Description

These dung flies are black in color, and approximately 4–5 mm (0.16–0.20 in) long. [4] They have two translucent wings that contain one dark spot near the tip of each. They look like ants, and often are difficult to identify without a microscope due to their appearance. [4]

Distribution

Typical habitat of S. cynipsea Alps of Switzerland Cow above Sertig Dorfli (23024185119).jpg
Typical habitat of S. cynipsea

Sepsis cynipsea dung flies are most commonly found in Europe. They prefer warm temperatures and can be more easily found from May to October in lower altitudes, and June to September in higher altitudes where the temperature is typically cooler. [1] In higher altitudes, female flies have shorter lifespans, are smaller, and lay fewer clutches of eggs. [1] They require fresh dung, primarily from cows and sheep, for reproduction. [4] They also eat nectar which is a source of sugar. [4]

Altitude effects

Sepsis cynipsea dung flies are often found in regions with varying altitudes, such as the Swiss Alps. [2] Out of the many different Sepsidae species that are found in these regions, Sepsis cynipsea flies prefer intermediate altitudes but are found at all altitudes where other species of dung flies are found. [2] In the areas where these fly species are prevalent, there is more species diversity at higher altitudes. [2] Higher altitude environments tend to be more variable, so species found at higher altitudes have to be better at adapting to environmental changes. [2] However, S. cynpisea flies at different altitudes enter diapause at the same time and stop producing eggs at the same time in the season. [5]

Temperature effects

The temperature during the larval phase of development impacts growth rates and final body size of Sepsis cynipsea. [6] S. cynipsea grow the best at intermediate temperatures compared to similar species. [6] However, in colder temperatures, S. cynipsea growth rates may increase so that they can reach adulthood before a cold season. Their growth rate also increases with warmer temperatures. [6] At 30 °C (86 °F), it takes approximately 7 days for S. cynipsea flies to mature from eggs to adults. [4] Resource availability, which can vary based on environmental conditions and competition with other species, also has an impact on the size of an adult body. [4] S. cynipsea primarily uses temperature to determine when to enter diapause. [5]

Competition

Because Sepsidae flies are often found in the same regions, there can be competition between species, like from S. neocynipsea which also prefers fresh cow dung for reproduction. However, some fly species, like S. duplicata prefer dry and old cow dung; this is known as niche differentiation. [2]

Mating

Reproduction

Sepsis cynipsea flies are most known for their mating practices that involve sexual conflict. Their mating habits have been extensively studied to better understand sexual selection, female choice, and reluctance in mating. [1] Sepsis cynipsea flies require fresh dung to mate, [7] and they prefer dung that is less than one hour old. [8] Females land on the fresh dung, where large numbers of males are already waiting, [9] and ingest fresh dung. The females lay their eggs on the dung, and while they are laying their eggs, a male gets on top of the female and guards her. [9] Males are not selective for females; they tend to mount the first female they encounter on the dung. [10] However, this is not copulation. The eggs she is laying are fertilized from a previous mate. [7] After she lays her eggs on the fresh dung, she and the male move to the grass that surrounds the dung pile, where they have the opportunity to mate, although most pairs do not, as the female successfully shakes the male off. [7] If they do make genital contact and mate, the next eggs she lays will probably be his. When the eggs hatch and the larvae emerge, the larvae eat the dung and then leave. [6] S. cynipsea flies have evolved to develop quickly so they avoid competition with other coprophagous organisms and before the dung dries up. [6]

Sexual conflict

Female Sepsis cynipsea flies are larger than the males, and because of this, a male cannot force a female to copulate with him. [9] However, there is a lot of male competition. [8] There are usually far more males than females on a dung pile, [9] which leads to the ability for females to be selective. [7] If a female does not want to mate with a male, she begins to shake her body, which either indicates to males that she does not want to mate [9] or functions shake the male off of her body. [3]

Mate choice

Larger males are more successful at mounting and mating with females, and larger females lay larger clutches of eggs. [4] In populations with greater mean body sizes, sexual selection is stronger compared to populations with smaller body sizes. [4] Once the male and female move into the grass after she lays her eggs, only about 40% of the pairs actually copulate. [7] And when they do, there is evidence to suggest that females get physically injured in the process. The male reproductive organ is spiney, and females are left with scars and have a higher mortality after mating. [3] This genital organ is most likely so armored to make it hard for the females to shake the males off; the male has to spin 180 degrees to get his genital organ out of the female. [3] If a female does not shake the male off, they copulate. The flies then find another dung site 2–4 days later to repeat the process. [7] This results in approximately six generations to progress during each breeding season. [4]

Evolution

Sexual dimorphisms

In the family Sepsidae, there is clear sexual dimorphism. The male foreleg, for example, differs greatly from a female foreleg, and differs in between Sepsidae species, as well. [10] The Morphology (biology) of the male foreleg evolved to aid the male in mounting the female and staying on her during her characteristic body shaking. [10] The male foreleg has evolved to have bristles, indentations, or bumps, which attach to the wing veins and cells on the female's wings. [10] In response to this, the female can bend her abdomen to prevent genital contact with the male. [10] In some Sepsidae species without adapted forelegs, the males have adapted an abdomen that bends to make contact with the female genitalia. [10] These sexually dimorphic characteristics can be very different between closely related species, so sexually dimorphic characteristics evolve quickly and are involved in speciation in the family Sepsidae.

Taxonomy

The family Sepsidae contains more than 320 species and 37 genera, which are globally widespread. [11] The sister species S. neocynipsea and S. cynipsea are found on different continents: S. neocynipsea in North America and S. cynipsea in Europe primarily. [12] Sepsis has more species than other genera of the family Sepsidae. [11] Sepsidae is monophyletic, with many different clades, including the Neotropical sepsids, the African clade, and the higher sepsids. [11] The sexually dimorphic traits, such as the moveable abdomens, evolved independently multiple times. [11]

Sister species

Sepsis neocynipsea is only recently diverged from Sepsis cynipsea. [12] Even though both species are widespread, overlap geographically, and have similar mitochondrial gene sequences, they have different behaviors and morphologies. [12] While S. neocynipsea is most commonly found in North America, it is also present in some of the same geographic locations that S. cynipsea is found in, like the Swiss Alps. [12] While S. cynipsea and S. neocynipsea cross-breeding events can produce hybrid offspring, these offspring are typically infertile or have low fertility. [12] Pre- and post-zygotic barriers between the species are still forming, so they have recently diverged. In S. cynipsea, female shaking during mating events is more visible than in S. neocynipsea. [13] S. cynipsea flies also have higher rates of successful matings per mating attempts than S. neocynipsea do. [13]

Genetics

There are high levels of genetic variability between flies, especially related to form. The heritability of these morphological traits ranges between 0.33-0.90 for males but is lower for females. [14] Male Sepsis cynipsea flies are smaller than females for all traits except for the width of the fore femur. [14] Body size and male leg features are selected for, so evolution works on these traits and contributes to sexual dimorphism.

Related Research Articles

<span class="mw-page-title-main">Sepsidae</span> Family of flies

The Sepsidae are a family of flies, commonly called the black scavenger flies or ensign flies. Over 300 species are described worldwide. They are usually found around dung or decaying plant and animal material. Many species resemble ants, having a "waist" and glossy black body. Many Sepsidae have a curious wing-waving habit made more apparent by dark patches at the wing end.

<span class="mw-page-title-main">Apple maggot</span> Species of fly

The apple maggot, also known as the railroad worm, is a species of fruit fly, and a pest of several types of fruits, especially apples. This species evolved about 150 years ago through a sympatric shift from the native host hawthorn to the domesticated apple species Malus domestica in the northeastern United States. This fly is believed to have been accidentally spread to the western United States from the endemic eastern United States region through contaminated apples at multiple points throughout the 20th century. The apple maggot uses Batesian mimicry as a method of defense, with coloration resembling that of the forelegs and pedipalps of a jumping spider.

<span class="mw-page-title-main">Sexual conflict</span> Term in evolutionary biology

Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between males and females. In one example, males may benefit from multiple matings, while multiple matings may harm or endanger females, due to the anatomical differences of that species. Sexual conflict underlies the evolutionary distinction between male and female.

<i>Phormia regina</i> Species of fly

Phormia regina, the black blow fly, belongs to the blow fly family Calliphoridae and was first described by Johann Wilhelm Meigen.

<i>Sepsis fulgens</i> Species of fly

Sepsis fulgens is a small ant-mimicking fly sometimes called the "lesser dung fly", though this can also refer to any member of the distantly related fly family Sphaeroceridae.

<i>Scathophaga stercoraria</i> Species of fly

Scathophaga stercoraria, commonly known as the yellow dung fly or the golden dung fly, is one of the most familiar and abundant flies in many parts of the Northern Hemisphere. As its common name suggests, it is often found on the feces of large mammals, such as horses, cattle, sheep, deer, and wild boar, where it goes to breed. The distribution of S. stercoraria is likely influenced by human agriculture, especially in northern Europe and North America. The Scathophaga are integral in the animal kingdom due to their role in the natural decomposition of dung in fields. They are also very important in the scientific world due to their short life cycles and susceptibility to experimental manipulations; thus, they have contributed significant knowledge about animal behavior.

<span class="mw-page-title-main">Female sperm storage</span>

Female sperm storage is a biological process and often a type of sexual selection in which sperm cells transferred to a female during mating are temporarily retained within a specific part of the reproductive tract before the oocyte, or egg, is fertilized. The site of storage is variable among different animal taxa and ranges from structures that appear to function solely for sperm retention, such as insect spermatheca and bird sperm storage tubules, to more general regions of the reproductive tract enriched with receptors to which sperm associate before fertilization, such as the caudal portion of the cow oviduct containing sperm-associating annexins. Female sperm storage is an integral stage in the reproductive process for many animals with internal fertilization. It has several documented biological functions including:

<i>Coelopa frigida</i> Species of fly

Coelopa frigida is a species of seaweed fly or kelp fly. It is the most widely distributed species of seaweed fly. It can be found on most shorelines in the temperate Northern Hemisphere. Other species of seaweed flies include Coelopa nebularum and Coelopa pilipes. C. frigida feeds primarily on seaweed, and groups of C. frigida flies tend to populate near bodies of water. Climate change has led to an increase in C. frigida blooms along shores, which creates a pest problem for human beach-goers. C. frigida is also an important organism for the study of sexual selection, particularly female choice, which is influenced by genetics.

Diptera is an order of winged insects commonly known as flies. Diptera, which are one of the most successful groups of organisms on Earth, are very diverse biologically. None are truly marine but they occupy virtually every terrestrial niche. Many have co-evolved in association with plants and animals. The Diptera are a very significant group in the decomposition and degeneration of plant and animal matter, are instrumental in the breakdown and release of nutrients back into the soil, and whose larvae supplement the diet of higher agrarian organisms. They are also an important component in food chains.

<i>Dryomyza anilis</i> Species of fly

Dryomyza anilis is a common fly from the family Dryomyzidae. The fly is found through various areas in the Northern hemisphere and has brown and orange coloration with distinctive large red eyes. The life span of the fly is not known, but laboratory-reared males can live 28–178 days. D. anilis has recently been placed back in the genus Dryomyza, of which it is the type species. Dryomyzidae were previously part of Sciomyzidae but are now considered a separate family with two subfamilies.

<i>Hylobittacus apicalis</i> Species of insect

Hylobittacus apicalis is a species of hangingfly in the order Mecoptera, and the only species within the genus Hylobittacus.

Sexual coercion among animals is the use of violence, threats, harassment, and other tactics to help them forcefully copulate. Such behavior has been compared to sexual assault, including rape, among humans.

Chionea scita is a species of crane fly in the family Limoniidae. C. scita is known as a type of snow crane fly because it is commonly seen walking on piles of snow during the winter months. These flies are also often observed in caves and heavily wooded areas. C. scita flies are small, hairy, wingless, and somewhat spider-like in appearance, unlike other flies.

<i>Prochyliza xanthostoma</i> Species of fly

The waltzing fly(Prochyliza xanthostoma) is a species of "carrion-feeding" cheese skippers, insects in the family Piophilidae and the order Diptera. P. xanthostoma is a member of the genus Prochyliza, which contains eleven species. The adult flies are found through North America and are brown-bodied, with orange and black coloring. Mating occurs on animal carcasses and male perform mating rituals; females engage in ejaculate feeding. The waltzing fly is known for its exaggerated sexual dimorphism and has thus become a prominent model for sexual dimorphism and larval behavior. These organisms are known as cheese skippers because when startled, the larvae can leap several inches into the air. P. xanthostoma is an important model organism for sexual selection, larval behavior, and adult reproductive success and survivability.

Derocephalus angusticollis is a fly in the family Neriidae. They are typically found on the east coast of Australia near rotting vegetation. Aggregating on the rotting bark of trees such as Acacia longigolia and other trees in New South Wales and southern Queensland. D. angusticollis flies found in the wild have accelerated speeds of development and age of mortality when compared to those in captivity. Derocephalus One characteristic of the neriid fly is that it demonstrates sexual dimorphism. Males have a larger build as well as exaggerated physical characteristics such as wider heads and longer limbs. Certain phenotypic characteristics are dependent on the diet of the parents.

<i>Drosophila silvestris</i> Species of fly

Drosophila silvestris is a large species of fly in the family Drosophilidae that are primarily black with yellow spots. As a rare species of fruit fly endemic to Hawaii, the fly often experiences reproductive isolation. Despite barriers in nature, D. silvestris is able to breed with D. heteroneura to create hybrid flies in the laboratory.

Sepsis thoracica, more commonly known as the black scavenger fly, a species of fly from the genus Sepsis and the family Sepsidae. It was discovered by Robineau-Desvoidy in 1830. It resembles a small flying ant. The fly is most commonly found inhabiting cow dung.

<i>Coelopa pilipes</i> Species of fly

Coelopa pilipes is a common European species of kelp fly. It was described by A. H. Haliday in 1838. Their appearance differs greatly from that of other Coelopa flies.

<i>Teleopsis dalmanni</i> Species of fly

Teleopsis dalmanni, synonym Cyrtodiopsis dalmanni, also known as the Malaysian stalk-eyed fly, is a species of fly in the family Diopsidae. T. dalmanni flies possess lateral elongations on their head capsules called eyestalks. These eyestalks play an important role in mate selection and as a result physical characteristic of the fly has been the subject of several studies on sexual selection, natural selection, and mating behavior.

Kathy Feng-Yi Su is an entomologist and evolutionary biologist from Singapore. She is an academic researcher, whose work focusses on sexual dimorphism particularly in the family Sepsidae.

References

  1. 1 2 3 4 5 Blanckenhorn, W. (1997). "Altitudinal life history variation in the dung flies Scathophaga stercoraria and Sepsis cynipsea". Oecologia. 109: 342–352. doi:10.1007/s004420050092.
  2. 1 2 3 4 5 6 Rohner, P. T., Bächli, G. , Pollini Paltrinieri, L. , Duelli, P. , Obrist, M. K., Jochmann, R. and Blanckenhorn, W. U. (2015), Distribution, diversity gradients and Rapoport's elevational rule in the black scavenger flies of the Swiss Alps (Diptera: Sepsidae). Insect Conserv Divers, 8: 367-376. doi:10.1111/icad.12114
  3. 1 2 3 4 Wolf U. Blanckenhorn, David J. Hosken, Oliver Y. Martin, Constanze Reim, Yvonne Teuschl, Paul I. Ward, The costs of copulating in the dung fly Sepsis cynipsea, Behavioral Ecology, Volume 13, Issue 3, May 2002, Pages 353–358, https://doi.org/10.1093/beheco/13.3.353
  4. 1 2 3 4 5 6 7 8 9 Blanckenhorn, Morf; Mühlhäuser, Reusch (1999). "Spatiotemporal variation in selection on body size in the dung fly Sepsis cynipsea". Journal of Evolutionary Biology. 12 (3): 563–576. doi: 10.1046/j.1420-9101.1999.00050.x .
  5. 1 2 Blanckenhorn, W. U. (1998). Altitudinal differentiation in the diapause response of two species of dung flies. Ecological Entomology 23, 1-8.
  6. 1 2 3 4 5 Blanckenhorn, W. U. (1999). Different growth responses to temperature and resource limitation in three fly species with similar life histories. Evolutionary Ecology 13: 395-409
  7. 1 2 3 4 5 6 Teuschl, Y; Blanckenhorn, Wolf U (2007). The reluctant fly: what makes Sepsis cynipsea females willing to copulate? Animal Behaviour, 73(1):85-97.
  8. 1 2 Parker, G..A. (1972). Reproductive Behaviour of Sepsis Cynipsea (L.) (Diptera: Sepsidae) I. a Preliminary Analysis of the Reproductive Strategy and Its Associated Behaviour Patterns, Behaviour, 41(1-2), 172-205. doi: https://doi.org/10.1163/156853972X00257
  9. 1 2 3 4 5 Blanckenhorn, W. U., Mühlhäuser, C. , Morf, C. , Reusch, T. and Reuter, M. (2000), Female Choice, Female Reluctance to Mate and Sexual Selection on Body Size in the Dung Fly Sepsis cynipsea. Ethology, 106: 577-593. doi:10.1046/j.1439-0310.2000.00573.x
  10. 1 2 3 4 5 6 Puniamoorthy, N., Su, K., & Meier, R. (2008). Bending for love: losses and gains of sexual dimorphisms are strictly correlated with changes in the mounting position of sepsid flies (Sepsidae: Diptera). BMC Evolutionary Biology, 8(1), 155. https://doi.org/10.1186/1471-2148-8-155
  11. 1 2 3 4 Zhao, L., Annie, A. S. H., Amrita, S., Yi, S. K. F., & Rudolf, M. (2013). Does better taxon sampling help? A new phylogenetic hypothesis for Sepsidae (Diptera: Cyclorrhapha) based on 50 new taxa and the same old mitochondrial and nuclear markers. Molecular Phylogenetics and Evolution, 69(1), 153–164. https://doi.org/10.1016/j.ympev.2013.05.011
  12. 1 2 3 4 5 Giesen, A, Schäfer, MA, Blanckenhorn, WU. Geographic patterns of postzygotic isolation between two closely related widespread dung fly species (Sepsis cynipsea and Sepsis neocynipsea; Diptera: Sepsidae). J Zool Syst Evol Res. 2019; 57: 80– 90. https://doi.org/10.1111/jzs.12239
  13. 1 2 Giesen, A., Blanckenhorn, W. U., & Schäfer, M. A. (2017). Behavioural mechanisms of reproductive isolation between two hybridizing dung fly species. Animal Behaviour, 132, 155–166. https://doi.org/10.1016/j.anbehav.2017.08.008
  14. 1 2 Reusch, T., & Blanckenhorn, W. U. (1998). Quantitative genetics of the dung fly Sepsis cynipsea: Cheverud’s conjecture revisited. Heredity, 81(1), 111–119. https://doi.org/10.1046/j.1365-2540.1998.00368.x
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.