Talk:Matriphagy

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Bibliography

Kim, K. W., Roland, C. and Horel, A. (2000), Functional Value of Matriphagy in the Spider Amaurobius ferox. Ethology, 106: 729-742. doi:10.1046/j.1439-0310.2000.00585.x

Suzuki, S., Kitamura, M., & Matsubayashi, K. (2005). Matriphagy in the hump earwig, Anechura harmandi (Dermaptera: Forficulidae), increases the survival rates of the offspring. Journal of Ethology, 23(2), 211-213. doi:10.1007/s10164-005-0145-7

Tizo-Pedroso, E., & Del-Claro, K. (2005). Matriphagy In The Neotropical Pseudoscorpion Paratemnoides Nidificator (Balzan 1888) (Atemnidae). Journal of Arachnology, 33(3), 873-877. doi:10.1636/s03-61.1

Additional References 10/4

1) Evans, T. A., Wallis, E. J., & Elgar, M. A. (1995). Making a meal of mother. Nature, 376(6538), 299. https://doi.org/10.1038/376299a0

2) Kim, K. W., Roland, C., & Horel, A. (2000). Functional Value of Matriphagy in the Spider Amaurobius ferox. Ethology, 106(8), 729–742. https://doi.org/10.1046/j.1439-0310.2000.00585.x

3) Nishimura, K. (2010). Kleptoparasitism and Cannibalism. In M. D. Breed & J. Moore (Eds.), Encyclopedia of Animal Behavior (pp. 253–258). Oxford: Academic Press. https://doi.org/10.1016/B978-0-08-045337-8.00279-5

4) Rienks, J. H. (2000). Extended Nest Residence and Cannibalism in a Jumping Spider (Araneae, Salticidae). The Journal of Arachnology, 28(1), 123–127.

5) Salomon, M., Aflalo, E. D., Coll, M., & Lubin, Y. (2015, March 4). Dramatic histological changes preceding suicidal maternal care in the subsocial spider Stegodyphus lineatus (Araneae: Eresidae) [research-article]. https://doi.org/10.1636/B14-15.1

6) Salomon, Mor, Schneider, J., & Lubin, Y. (2005). Maternal Investment in a Spider with Suicidal Maternal Care, Stegodyphus lineatus (Araneae, Eresidae). Oikos, 109(3), 614–622.

7) Suzuki, S., Kitamura, M., & Matsubayashi, K. (2005). Matriphagy in the hump earwig, Anechura harmand (Dermaptera: Forficulidae), increases the survival rates of the offspring. Journal of Ethology, 23(2), 211-213. https://link.springer.com/content/pdf/10.1007%2Fs10164-005-0145-7.pdf

8) Tizo-Pedroso, E., & Del-Claro, K. (2005). Matriphagy in the neotropical pseudoscorpion paratemnoides nidificator (balzan 1888) (atemnidae). Journal of Arachnology, 33(3), 873–877. https://doi.org/10.1636/S03-61.1

9) Toyama, M. (1999). Adaptive advantages of maternal care and matriphagy in a foliage spider,Chiracanthium japonicum (Araneae: Coubionidae). Journal of Ethology, 17(1), 33–39. https://doi.org/10.1007/BF02769295

10) Toyama, M. (2003). Relationship between reproductive resource allocation and resource capacity in the matriphagous spider, Chiracanthium japonicum (Araneae: Clubionidae). Journal of Ethology, 21(1), 1–7. https://doi.org/10.1007/s10164-002-0067-6

Notes on references: This study evaluated costs to mother and benefits to offspring of matriphagy behavior in a species of spider, which will be important for highlighting the function of this behavior and solidifying the list of species that engage in matriphagy (Kim, Roland, & Horel, 2000).

Here the benefits of matriphagy were investigated in the offspring of a species of spider via experimental manipulation of mother attendance. This will be important information to include in the section on the function of matriphagy behavior and will add to the species list (Toyama, 1999).

Both of these papers explain the significance of maternal resources on the size of the offspring, and thus relate it back to offspring fitness (Toyama, 2003; Mor Salomon, Schneider, & Lubin, 2005).

This paper talks about Menemerus bracteatus engaging in matriphagy behavior - could be a potential new species to add to the list (Rienks, 2000).

This study found that mothers store food for their young and matriphagy is a method of parenting (providing food for their young). The study was conducted in an Australian social spider, Diaea ergandros. They found that matriphagy, an extreme form of parenting, is more prevalent in spiders that lay a single clutch and it improves sociality by reducing sibling cannibalism (Evans, Wallis, & Elgar, 1995)

In the spider Stegodyphus lineatus Latreille 1817 (Eresidae), maternal care is extreme and irreversible: mothers regurgitate food for the young and then die when consumed by them (matriphagy). This group examined whether the mother's midgut tissues undergo structural changes in preparation for regurgitation and matriphagy. They found that the midgut diverticula (MD) tissues start to degrade during the egg sac incubation period. At matriphagy, the abdomen is filled with liquid containing nutritional vacuoles, which the young imbibe after piercing the female's abdomen. Finally, they conclude that the MD undergoes a gradual degradation process that maximizes the nutritional potential of the female's body and finally enables complete consumption of her soma (M. Salomon, Aflalo, Coll, & Lubin, 2015).

This group studied the Paratemnoides nidificator (Balzan 1888) in a tropical savanna system where females were responsible for all nymphal care. They found, for the first time in pseudoscorpions, the occurrence of matriphagy behavior by the offspring. During conditions of food deprivation, the mother went out of the nest and passively awaited the protonymphs' attack, not reacting to the capture nor to the nymphs feeding on her body. They hypothesize that this extreme form of parental care can reduce cannibalism among protonymphs and facilitate the evolution of social behavior in pseudoscorpions (Tizo-Pedroso & Del-Claro, 2005).

This paper studies the consumption of Anecura hamrandi, the hump earwig, by their offspring after their care. Matriphagy ended up indicating a delayed dispersal of the nymphs with an increase in their survival rate, yet survival was the same if mothers were removed and the offspring were supplied with sufficient food. This suggests nymph survival is dependent on food availability that hump earwig females are semelparous. (Suzuki, S., Kitamura, M., & Matsubayashi, K., 2005) Rebecca.f.lee (talk) 15:36, 4 October 2018 (UTC)

Introduction

Matriphagy is the consumption of the mother by her offspring.[1][2] The behavior generally takes place within the first few weeks of life and has been documented in some species of insects, nematode worms, scorpions, and other arachnids.[3][4]

The specifics of how matriphagy occurs vary among different species, but the process is best described in Stegodyphuts lineatus, where the mother harbors nutritional resources for her young through food consumption. The mother is able to regurgitate small portions for her growing offspring, but between 1-2 weeks after hatching the progeny capitalize on this food source by eating her alive. Typically, this behavior only acts on the biological mother of the young.

Spiders that engage in matriphagy produce offspring with higher weights, shorter and earlier moulting time, larger body mass at dispersal, and higher survival rates than clutches deprived of matriphagy. In some species, matriphagous offspring were also more successful at capturing large prey items and had a higher survival rate at dispersal. These benefits to offspring outweigh the cost of survival to the mothers and help ensure that her genetic material is passed to the next generation, thus perpetuating the behavior.

Overall, matriphagy is an extreme form of parental care that stands in stark contrast to other forms such as extended parental care and protection found in arachnids and other insects. The uniqueness of this phenomenon has led to several expanded analogies in human culture and contributed to the pervasive fear of spiders throughout society.

Etymology

• This section, although brief in manner, is necessary to highlight the literal translation of the word, which therefore brings enhanced meaning to the term. • Matriphagy can be broken down into two components: - Matri- (mother) - -phagy (to feed on) (“matriphagy - Wiktionary”)

Description

• This section will give a detailed description of matriphagy behavior in different species (how it happens, what changes within the body of the mothers, and what circumstances that led to the development of this behavior). • Matriphagy behavior generally consists of offspring consuming their mother; however, different species exhibit different versions of this behavior and this section will describe these variations. • Amaurobius ferox (subsection) - (Salomon et al., 2015) and (Kim, K. W., & Horel, A., 1998)

This matriphagy behavior is initiated by communication through web vibrations between the mother and her offspring. These web vibrations tell the offspring to go towards her abdomen

• 1 day after the emergence of her offspring, the mother produces a second batch of eggs. These eggs are known as trophic eggs. Her offspring consumes these eggs immediately after they have been lain.
• Then for the first 3 days after laying the trophic eggs, the mother keeps to herself, away from her offspring, until after the fourth day, when the mother begins pulling at the web while approaching her offspring.
• 2-3 hours before the mother is consumed, she increases her activity by drumming on the web, brushing her offspring off of her back, and jumping.
  • This drumming may “activate” the young, while jumps may “inhibit” them.
• During her last 20-30 minutes alive, her activity increases even more (more drumming and more jumping) and more of the offspring climb onto her.
• At the very end, she presses her body onto her offspring and then relaxes her whole body and allows her offspring to consume her. The offspring actually move collectively towards her abdomen (opisthosoma) to begin consumption through sucking. This initial feeding takes up to 1 hour. The mother’s body is then kept for several weeks for the offspring to continually go back to for nutrients.
  • Pressing her body might act as a suggestion to the offspring to consume her.
• 3-4 days after consummation of the trophic eggs, the offspring experience their first post emergence moult and afterwards consume their mother a day later.
• Offspring older than 4 days have been found to unwillingly participate in matriphgay. This shows that the behavior in this species is very dependent on time of development of the offspring.
• Interestingly, if the mother loses her brood, then she is able to produce another clutch. Also, a mother can be eaten by offspring that is not her own, however this does not apply for a virgin female.
• All of the drumming and jumping indicate communication between the mother and her offspring, which may be how the offspring know when and where to consume their mother.

• Anechura harmandi (subsection) - (Suzuki et al., 2005)

• Offspring eat their mothers
• It has been shown that the removal of mothers reduces survival in these hump earwig offspring, however few are able to survive and end up dispersing the nest earlier than those who were able to gain nutrients from their mother’s body.
• Mothers of this species cannot produce a second brood.
• Usually, when mothers of this species decide to reproduce, they reproduce early in the season at low temperatures mainly to avoid predation (especially since if they lose their one brood, then they will not be able to produce another). However, during this time, there isn’t much food available, which makes the mother the next best choice for nutrients.

• Diaea ergandros (subsection) - (Evans et al., 1995)

• Mothers of this species store nutrients and food in trophic eggs that are not laid. The nutrients are then converted into haemolymph, which can now be consumed by her offspring through her leg joints. During consumption, the mother loses the ability to move and her abdomen shrinks. The rest of the egg is then consumed during the consumption of the mother’s whole body.
• These trophic eggs are actually unusually large oocytes that are only found in mothers that have already lain their single clutch (after laying eggs, their ovaries shrivel, but then they develop into ovaries with these larger and fewer oocytes). They are so large, that they cannot physically get through the mother’s oviducts, which explains why they can never be lain.
• These mothers only lay one clutch.
• Depending on the body mass of the mother, cannibalism within the offspring may occur earlier or later. (This study also suggests that matriphagy may reduce cannibalism within siblings).

• Paratemnoides nidificator (subsection) - (Tizo-Pedroso, E., & Del-Claro, K., 2005)

• The mother exits the nest and waits to be consumed during periods of food deprivation.
• Her offspring follow her out of the nest to gather around her and then grab her legs. They feed through her leg joints.
• Upon finishing consumption, the mother’s exoskeleton is thrown out of the tree bark (where they are living) and then the offspring begin hunting together.
• If the mothers live in a group, they are able to produce more than one clutch during her lifetime.
• Matriphagy behavior in this species may prevent cannibalism for occurring.

• Stegodyphus lineatus (subsection) - (Salomon et al., 2015)

• Offspring of this species, when first emerged, are too young to catch and ingest their own prey no their own, so they rely on their mother’s regurgitated fluid for feeding. Without this fluid, they would die.
• Mothers’ midgut tissues begin slowly degrading during the middle of egg incubation period of their offspring. Even before that, mating might actually trigger an increase in the production in digestive enzymes to better digest the mother’s prey for the sake of helping her retain more nutrients for the offspring to consume later.
• Mothers first regurgitate food for their offspring for a short period of time, while their midgut tissues continue to gradually degrade and, as a result, completely liquefy. This degradation is done in such a way that maximizes the amount of nutrition of the mother’s body in the liquid.
• Her liquified midgut tissues are used to help regurgitation by acting as the regurgitation fluid, which ends up accelerating this degradation/liquifying process.
• A mother’s abdomen fills with liquid containing nutritional vacuoles and their offspring are actually able to attain this liquid by puncturing into their mother’s abdomen.
  • These nutritional vacuoles are made after digesting prey with enzymatic digestive fluid from a previous meal and then sucking up the degraded tissues of their prey.
• After approximately 2-3 hours, the offspring completely consume all of their mother’s body fluids. Only her exoskeleton remains.
• By the end, ~95% of a mother’s body mass will be consumed by her offspring.
• This intense maternal care can also be explained on why mothers of this species spend so much effort, time, and other resources into a single reproductive event. In the end, she only has one clutch, unless her previous clutch is lost or taken by others.
• This behavior will only occur between mothers and their own offspring and in mothers who had recently just laid her eggs with offspring that are not her own. Virgin females will not aid in this feeding, indicating importance of reproductive stage even before matriphagy behavior occurs.

Evolution

• This section is going to focus on the adaptive value of matriphagy in terms of the benefits provided to the offspring and the costs borne by the mother. This functional analysis of matriphagy will help shed light on why this unusual and extreme form of care has evolved and been selected for.

• Benefits to Offspring (subsection) - Study conducted by Kim et al. (2000) in Amaurobius Ferox.

• Consuming the mother is a source of nutrition which is important for growth and development.
• The body mass and opisthosoma length of spiderlings increased (2.5 fold) after matriphagy compared to before (opisthosoma is the posterior part of the body in spiders, analogous to the abdomen). Additionally, body mass was higher for the group of spiderlings that engaged in matriphagy as compared to the group that did not (similar results were found by Toyoma et al., 1999).
• Matriphagy also advanced molting time. Molting is the growing of a larger exoskeleton and shedding the old one. Advancement of molting time means that the spiders are growing at a faster rate.
• The matriphagy group of spiderlings experienced significantly greater survival rates compared to the no-matriphagy group at dispersal (Suzuki et al., 2005). The spiders that engaged in matriphagy also had a larger body mass/size at dispersal, indicative of higher fitness (Salomon et al., 2005).
• Predation started earlier in the no-matriphagy group (around the time matriphagy was expected to occur) because the spiderlings needed food to survive. However, the no-matriphagy spiderlings only hunted small prey whereas the spiders that engaged in matriphagy were successful at hunting larger prey, and this group also showed more complete prey consumption.
• Evans et al. 1995, also argue that matriphagy improves sociality in spiders, primarily by reducing sibling cannibalism.

• Costs to mother (subsection) - (Kim et al., 2000)

• Unlike other milder forms of parental care, matriphagy ends with the life of the mother, the gravest of all costs. So, why has it evolved? In order to answer this, we need to look at costs to the mother in terms of reproductive output, egg sac development and number of young (i.e. are offspring more successful if the mother evades matriphagy and reproduces again?).
• Only 79% of the females who were separated prior to matriphagy produced second egg sacs and only 42% of these developed completely (compared to the >90% development of egg sacs in the first brood).
• Number of spiderlings in the second brood were significantly lower than in the first brood. Additionally, these individuals were also smaller than the spiders in the first brood.
• Females that were offered the opportunity to successively lay two egg sacs had a lower expected output of dispersing offspring than females that were victims of matriphagy which produced only a single clutch

In conclusion, these results show that spiderlings that engage in matriphagy benefit a lot more than spiderlings that do not engage in this behavior. Further, the progeny of females that escape matriphagy to lay a second brood are significantly less successful than those that ate their mother the first time around. Together, these results shed light on why this unusual and extreme form of parenting has been selected for and has evolved.

Other forms of Parental Care

Here we will compare matriphagy to other parental care methods in similar species and other arachnids; as a result, the audience will be able to realize the costs and benefits of other maternal parenting styles and realize the reasons for matriphagy in certain situations. (will divide into SUBSECTIONS, by the parental care methods & by species)

• Extended Care in Coelotes terrestris (subsection) - (Gunderman et. al, 1997); This section will take a look at spider parental care that differs from matriphagy and involves extended care for the young

• Detail the costs and benefits of maternal care in a subsocial spider Coelotes terrestris as an example of extended care toward its progeny
• The mother guards its egg sac for 3-4 weeks and stays with its young from the time of emergence until dispersal approximately 1 month later
• Comparisons of fitness of females performing care versus females separated from their egg sac will be analyzed
• Benefits exist in that protection of egg sacs from predation and parasites as well as supplying the young with food will allow for increased survival rate and development of many of the spiderlings
• Costs include decreased ability to produce a second clutch (similar to species that exhibit matriphagy) but this is variable according to the stage in the reproductive cycle; guarding of the egg sac has a low cost when comparing it to benefits

• Mother-Offspring aggregation in the European earwig (subsection) - (Gomez et al, 2013)

• Coadaptation of Forficula auricularia (European earwig) parents and offspring are age-dependent; similar to A. ferox and other species in the sense that timing of parental care affects how offspring will react
• Offspring and parents interact repeatedly over time of parental care and their behavior is adjusted dynamically and adaptively depending on the time of interaction
• Maternal care is beneficial, but not vital, for their offsprings survival
• Care is most intense during the first larval instar as opposed to later points in development, as measured by a stability in aggregation levels between the parent and the offspring at early points, with a steep decline in aggregation levels over time or with different families
• Nymph survival and female-offspring aggregation have a positive correlation when care is at its highest stages, which is often in the early stages of development

• Parental care and production in Euscorpius flavicaudis (subsection) - (Dumke, 2017)

• Maternal care in the scorpion Euscorpius flavicaudis is primarily involved for predation protection as opposed to food foraging
• Differs in the sense that presence or absence of the mother does not have an effect on juvenile survival, assuming that conspecific scorpions were kept from other scorpions
• If scorpions had access to other scorpions in a group, the presence of the mother prevented predation, but absence suggest extremely high brood mortality rates averaging 99%
• Thus, avoidance of predation is the primary selective advantage in parental care
  • (This section will focus on the fact that this is true; research used as supplement)

• Extended care in the Australian crab spider (subsection) - (Benton, 1991)

• Maternal care is extended in Xysticus bimaculatus; here the crab spiders are subsocial species, and produce extremely small clutches
• Potential that this reveals that there is a limit in how many offspring they are capable of caring for
• Offspring obtain crucial benefits beyond nutritional independence and still require extensive maternal food provisioning
• Prey-sharing occurred regardless of maternal presence; exploitative feeding behavior is involved and reflects a communal feeding style

Cultural Significance

• This section will connect the biological behavior of matriphagy to human behavior, rhetoric, and pop culture. Information on cultural significance will broaden our target audience and highlight the importance of the evolution of this behavior beyond the species specific, biological level. • Rhetorical matriphagy is a concept dubbed by Dr. Luke Winslow in connection with critiques of online higher education offerings. (Winslow, 2017)

• Higher education assumes the role of the mother, neoliberalism assumes the role of the hatchlings, and online education discourse assumes the role of the mother’s symbolic resources, which are used to attract the hatchings and eventually cause them to eat her alive for these resources.
• Matriphagy is a less than ideal survival mechanism in response to an environment with poor conditions and few natural resources, but it does ensure the survival of the mother’s genes via her hatchlings. Similarly, online education does not consider itself at the same level has traditional forms of higher education but does provide an equal opportunity for all to attain such education in a cost-effective way that purports to satisfy most stakeholders in the process.

• Matriphagy perpetuates a long held fear of arachnids in human society. (Barness, 2014) • Matriphagy serves as an instinctive form of altruism, a highly popularized and desirable concept in many human cultures. (Wilson, 2016)

• Altruism defined as “intentional action ultimately for the welfare of others that entails at least the possibility of either no benefit or a loss to the actor”
• Matriphagy “intentional” behavior, insofar as the mother is programmed by natural selection to behave in such a way (only participating mothers have offspring that survive, thus perpetuating cannibalistic behavior through generations)
• Human standard for altruism tainted by moral virtues such as rationality, trust, and reciprocity – concepts that are not seen in purely biological interactions.

List of species Theridion impressum, Eresidae: Cheiracanthium japonicum Rebecca.f.lee (talk) 15:31, 16 October 2018 (UTC)

Wiki Education Foundation-supported course assignment

This article was the subject of a Wiki Education Foundation-supported course assignment, between 27 August 2018 and 7 December 2018. Further details are available on the course page. Student editor(s): Khk17, Viditbhandarkar, Amtsai77, Rebecca.f.lee. Peer reviewers: Mab157, Pwngrl777, Yanabey29.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 00:43, 18 January 2022 (UTC)

Behavioral Ecology--Peer Review

General review-

Overall, while this is a very in-depth and detailed article, I think it is quite repetitive and long. I definitely finished the article having a really, really good understanding of matriphagy, so good job with that! However, many rambling descriptions could be cut down, which would reduce repetition and also make the article as a whole more concise. The drawn-out sentences with super broad generalizations and casual language creates a less-than-scientific/professional tone for the article. Additionally, you rely very heavily on single, primary sources that are for many of the sections. Sometimes the same source is used for every citation in a section, and multiple times in other sections. Try to vary sources and use secondary reviews as well.

Some more specific comments- There is no need to posit questions in the article, e.g. "So, why has it evolved?". I get that you're trying to make it interesting, but it's better to just present the answer to the questions.

In the Costs to the mother and Summary sections, you lose the neutral presentation of facts. It reads more like a journal article trying to convince me.

Including the other forms of parental care seems to lose the main goal of the article - if the point of this page is matriphagy, why spend a lot of time explaining other forms of parental care? There are many many different types and could each be their own article. If you have to keep this section, maybe briefly describe it all in one paragraph and then link to some pages that have the other forms of care. Otherwise you can probably just cut the whole thing.

Similarly, the cultural significance part also feels very forced. The sentences don't flow together well, Andean aren't really explained, so it seems like you just picked some lines from the source and put them in without really understanding or summarizing what was going on. This section in general seems fairly irrelevant to the point of the page, so again, if you have to have it, maybe just a few clear, concise sentences in your own words linking it to the main topic.

Some sentences that had difficult wording/incorrect grammar "communicate between to her offspring" "Another three days later, the mother becomes reserved and away from her offspring" "await to be consumed by their offspring" And the beginning of the stegodyphus lineatus section is fragmented and starts off without establishing enough info.

Hopefully these comments are helpful, let me know if you have any questions. Overall great job and good luck on your page!

Pwngrl777 (talk) 21:17, 6 November 2018 (UTC) Gabe

Peer Review

Overall the article is very well written out and thought out! After reading the article I came away with a much better understanding of Matriphagy and the reasons behind it (cool but still eew) however I feel like not all of the content is fully neutral. For example I would take out the last sentence of the introduction because it doesnt really add much to the paper and it is not cited.

There are also a few grammar issues such as in the Amaurobius ferox section where you say "Another three days later, the mother becomes reserved and away from her offspring.[10] Then, around the fourth day, matriphagy behavior commences when the mother begins using web vibrations to communicate between to her offspring." You should reword this part. In general just look over your grammar and sentences for the entire paper because it is a consistent issue.

Also for the Description of behavior section, you are not doing much describing, instead you are giving examples so maybe change the title to examples and shorten the Amaurobius ferox section to better flow with the rest of the section.

The rest of your article looks great though! It is very thorough (maybe a little too repetitive) but I like the cultural significance at the end! — Preceding unsigned comment added by Mattextract (talk • contribs) 16:19, 8 November 2018 (UTC)

Caecilian skin-feeding

Caecilian skin-feeding is currently included in both the "Description of Behavior" section and the "Forms of maternal care similar to matriphagy" section. I propose that it should only be in the "Forms of maternal care similar to matriphagy", as the behavior among Caecilian young is not fatal to the mother (https://pubmed.ncbi.nlm.nih.gov/16612382/), making it more akin to the provisioning of milk or trophic eggs than to provisioning of vital tissues.

Does anyone object to this change? FlamedTigerSnail (talk) 03:28, 30 March 2023 (UTC)