The Nature of Cancer: Unifying Evolutionary Theory in Cancer Biology

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Description
Evolutionary theory provides a rich framework for understanding cancer dynamics across scales of biological organization. The field of cancer evolution has largely been divided into two domains, comparative oncology - the study of cancer across the tree of life, and…

Evolutionary theory provides a rich framework for understanding cancer dynamics across scales of biological organization. The field of cancer evolution has largely been divided into two domains, comparative oncology - the study of cancer across the tree of life, and tumor evolution. This work provides a theoretical framework to unify these subfields with the intent that an understanding of the evolutionary dynamics driving cancer risk at one scale can inform the understanding of the dynamics on another scale. The evolution of multicellular life and the unique vulnerabilities in the cellular mechanisms that underpin it explain the ubiquity of cancer prevalence across the tree of life. The breakdown in cellular cooperation and communication that were required for multicellular life define the hallmarks of cancer. As divergent life histories drove speciation events, it similarly drove divergences in fundamental cancer risk across species. An understanding of the impact that species’ life history theory has on the underlying network of multicellular cooperation and somatic evolution allows for robust predictions on cross-species cancer risk. A large-scale veterinary cancer database is utilized to validate many of the predictions on cancer risk made from life history evolution. Changing scales to the cellular level, it lays predictions on the fate of somatic mutations and the fitness benefits they confer to neoplastic cells compared to their healthy counterparts. The cancer hallmarks, far more than just a way to unify the many seemingly unique pathologies defined as cancer, is a powerful toolset to understand how specific mutations may change the fitness of somatic cells throughout carcinogenesis and tumor progression. Alongside highlighting the significant advances in evolutionary approaches to cancer across scales, this work provides a lucid confirmation that an understanding of both scales provides the most complete portrait of evolutionary cancer dynamics.
Date Created
2023
Agent

Helping in Times of Need Increases Dispositional Empathic Concern Over Time

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Description
Previous work suggests that lower-income individuals are more likely to engage in mutual aid as a means to manage risk, giving rise to a psychology that is other-oriented, including an empathetic disposition and a proclivity to help people in need.…

Previous work suggests that lower-income individuals are more likely to engage in mutual aid as a means to manage risk, giving rise to a psychology that is other-oriented, including an empathetic disposition and a proclivity to help people in need. While no study has directly investigated whether helping in times of need increases dispositional empathic concern over time, this assumption is deep-seated among social psychologists. Employing a two-year longitudinal survey of US adults (N = 915), I show that people who experience more needs report helping others when in need a greater number of times, in turn leading to a small but positive increase in their empathetic disposition. This study also identifies the types of needs that elicit empathic concern (i.e., those that arise from unpredictable sources of risk), and shows why cultivating an empathetic disposition is likely to pay off in the long run: those who provide help are more likely to receive help during future times of need. Moreover, this study identifies the types of targets for whom providing help might cultivate an empathetic disposition: those with whom people are likely to share lower interdependence. While previous theoretical frameworks posit that empathic concern selectively directs investment towards interdependent others, providing help to non-interdependent targets might allow people to build positive interdependence with prospective risk pooling partners. Cultivating an empathetic disposition and building interdependence with prospective risk pooling partners can allow people to manage needs that arise from unpredictable sources of risk.
Date Created
2023
Agent

An Evolutionary Perspective on Neoplastic Disease Across the Tree of Life

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Description
Cancer is a disease of multicellularity, with deep evolutionary origins. As such, the forces of both evolution and natural selection operate on multiple scales to govern tumor dynamics. As multicellular organisms increase in complexity, cellular-level fitness must be controlled in…

Cancer is a disease of multicellularity, with deep evolutionary origins. As such, the forces of both evolution and natural selection operate on multiple scales to govern tumor dynamics. As multicellular organisms increase in complexity, cellular-level fitness must be controlled in order to maintain organismal-level fitness. Mutations that might provide a benefit at the cellular level by allowing for rapid proliferation are subject to the same forces that function on the organismal level, wherein cancer suppression is a benefit – especially as organisms increase their body size and lifespan. In order to maintain these large cellular bodies and long lifespans, organisms must increase their means of cancer suppression, and it is likely that these two phenomena co-evolved together. On a smaller scale, the cooperative dynamics of circulating tumor cell (CTC) clusters engage in cooperation to form networks of connected single cells that provide protection, stability, and cooperative sharing of resources to enhance their survival as they detach from a primary tumor and metastasize at secondary sites. This work seeks to explore the phenomenon of multi-level selection in neoplastic disease by examining A) the mechanisms of cancer suppression at multiple scales, B) the ecological resilience and stability of cooperating cellular clusters and C) a large-scale dataset on cancer prevalence across mammals, sauropsids (birds and reptiles), and amphibians, illuminating the evolutionary life history characteristics that explain the tradeoffs between cancer suppression and overall organism fitness. By taking an ecological and evolutionary approach to understanding cancer, novel strategies of cancer treatment may be discovered alongside fundamental discoveries about the fundamental forces of selection that govern evolutionary dynamics from the cellular to the organismal scale.
Date Created
2022
Agent

Does Genetic Conflict Contribute to Pregnancy Complications and Postpartum Health and Behavior?

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Description
Pregnancy is often described as one of the most cooperative ventures that a woman can experience in her lifetime. But when one considers the biological changes that occur during pregnancy, it becomes clear that pregnancy is not as cooperative as…

Pregnancy is often described as one of the most cooperative ventures that a woman can experience in her lifetime. But when one considers the biological changes that occur during pregnancy, it becomes clear that pregnancy is not as cooperative as it seems on the surface. The current research uses a genetic conflict framework to predict how underlying conflict between mother and fetus over resource transfers is expected to alter eating behavior and food preferences, and how these changes in eating behavior and preferences should then be associated with certain pregnancy complications. Across two studies, women who had recently had a baby (Study 1) or were currently pregnant (Study 2) recalled changes in their eating behavior during pregnancy as well as any pregnancy complications they experienced during that pregnancy. Providing partial support for the hypotheses, women who reported increased vomiting in response to maternal-favoring foods were more likely to experience preeclampsia during pregnancy. In addition, the results provided preliminary evidence that changes in pregnancy eating behavior were associated with an increased the likelihood of experiencing high blood pressure, gestational diabetes, and infections during pregnancy. Taken together, these studies show that the framework of genetic conflict makes testable predictions about the relationship between eating behavior in pregnancy and pregnancy complications, and that several pregnancy complications that are relevant to genetic conflict (high blood pressure, pre-eclampsia, gestational diabetes, and infection) are associated with changes in eating behavior in pregnancy. Future research should continue to investigate how genetic conflict influences the relationships between pregnancy eating behavior, pregnancy complications, and how these associations impact postpartum health.
Date Created
2022
Agent

Associations Between Messaging, Reactance, and Self-Esteem

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Description

This paper explores the effect of messaging type and reactance on the receptiveness individuals have towards a message meant to boost their self-esteem. A 2 (Messaging: Implicit | Explicit) x 2 (Reactance: High | Low) between-subjects study was conducted to…

This paper explores the effect of messaging type and reactance on the receptiveness individuals have towards a message meant to boost their self-esteem. A 2 (Messaging: Implicit | Explicit) x 2 (Reactance: High | Low) between-subjects study was conducted to test the hypothesis that an indirect (implicit) message will have the most positive effect on self-esteem when people experience low reactance compared to people who receive direct (explicit) messages and experience high reactance. To test these hypotheses, we recruited 708 psychology students. We found that messaging type did not influence self-esteem, nor a messaging type by reactance condition interaction. However, we found that reactance, when high, had a more positive effect on self-esteem than when low. In conclusion, a message inducing a high reactance is more receptive than a message inducing low reactance.

Date Created
2022-05
Agent

Modeling the Evolution of Senescence & Apoptosis in the Emergence of Multicellularity

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Description

Cooperative cellular phenotypes are universal across multicellular life. Division of labor, regulated proliferation, and controlled cell death are essential in the maintenance of a multicellular body. Breakdowns in these cooperative phenotypes are foundational in understanding the initiation and progression of…

Cooperative cellular phenotypes are universal across multicellular life. Division of labor, regulated proliferation, and controlled cell death are essential in the maintenance of a multicellular body. Breakdowns in these cooperative phenotypes are foundational in understanding the initiation and progression of neoplastic diseases, such as cancer. Cooperative cellular phenotypes are straightforward to characterize in extant species but the selective pressures that drove their emergence at the transition(s) to multicellularity have yet to be fully characterized. Here we seek to understand how a dynamic environment shaped the emergence of two mechanisms of regulated cell survival: apoptosis and senescence. We developed an agent-based model to test the time to extinction or stability in each of these phenotypes across three levels of stochastic environments.

Date Created
2021-12
Agent

Perspective-Taking in Roleplaying Games and Empathy

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Description

Empathy includes multiple components, including empathic concern, perspective-taking, and motivation to empathize. Various perspective-taking interventions have been found to be useful in increasing empathy. Games can be utilized as such interventions, especially when they involve perspective-taking components. The similarities between…

Empathy includes multiple components, including empathic concern, perspective-taking, and motivation to empathize. Various perspective-taking interventions have been found to be useful in increasing empathy. Games can be utilized as such interventions, especially when they involve perspective-taking components. The similarities between tabletop roleplaying games and various empathy-building interventions suggests that tabletop roleplaying games may be an intervention option that is already played for enjoyment. This study examines the influence of tabletop roleplaying games on motivation to empathize. Participants played a short tabletop roleplaying game and then were asked to choose between describing and empathizing with refugee targets over a series of trials. There is a potential main effect of tabletop roleplaying games on motivation to empathize, but this main effect is absent when controlling for self-other-overlap. It appears that self-other-overlap influences motivation to empathize. However, this study was underpowered, and the main effect of roleplay may have been detected if more participants were involved. Thus, there is potential that tabletop roleplaying games may influence motivation to empathize, and future research should examine this while considering the limitations of this study.

Date Created
2021-05
Agent

Examining reputation from a life history perspective

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Description
An individual’s reputation can be beneficial or detrimental to their exchanges with others,
and these exchanges may be critical for achieving evolutionary goals, such as reproduction.
Depending on their reputation, an individual may or may not gain access to resources in order…

An individual’s reputation can be beneficial or detrimental to their exchanges with others,
and these exchanges may be critical for achieving evolutionary goals, such as reproduction.
Depending on their reputation, an individual may or may not gain access to resources in order to
achieve their evolutionary goals. Reputation is typically described as being “positive” and
“negative,” but the current study aimed to identify potential nuances to reputations beyond the
traditional dichotomy. It was hypothesized that different types of reputations (such as “friendly”,
“dishonest”, and “aggressive”) would group together in categories beyond “positive” and
“negative.” Additionally, individuals with different life history strategies might find different
reputations important, because the reputations they find most important may help them get the
kinds of resources they need to attain their specific evolutionary goals. Therefore, it was also
predicted that the importance individuals place on different types of reputations would vary as a
function of life history strategy. Exploratory factor analysis identified a five factor structure for
reputations. Individuals also placed varying levels of importance on different types of
reputations, and found some reputations more important than others depending on their life
history strategy. This study demonstrates that reputational information is more nuanced than
previously thought and future research should consider that there may be more than just
“positive” and “negative” reputations in social interactions.
Date Created
2020-12
Agent

Attitudes toward asking for help: Effects of Perceived Social Status on help-seeking behaviors

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Description
Humans engage in many forms of cooperation within social groups, creating the ability for people help others when they are in need. One specific type of cooperation helps alleviate need and manage risk in both kin and non-kin relationships. However,…

Humans engage in many forms of cooperation within social groups, creating the ability for people help others when they are in need. One specific type of cooperation helps alleviate need and manage risk in both kin and non-kin relationships. However, how people ask for help or notice when someone else is in need have not received systematic investigation. In this study, participants’ self-reported socioeconomic status (SES) was collected along with information about their willingness to engage in a variety of help-seeking behaviors in certain situations. Participants’ general emotions and attitudes associated with certain aspects of asking for help were also collected. It was predicted that people with lower SES would be more reluctant to ask due to more negative emotions associated with and more instances of needing to ask for help. People with higher SES were predicted to be more likely to ask for help due to fewer negative emotions associated with asking and less need to ask for help overall. We found that people with lower SES were generally less willingness to engage in help-seeking behaviors compared to those of higher SES. However, results did not support the hypothesis that people with lower SES would experience more negative emotions associated with asking for help. Considering these results, further studies should investigate willingness to seek financial help versus other types of help in personal relationships and from institution-based assistance programs. Future research should also seek to determine how feelings of entitlement in individuals with higher SES affect willingness to ask for and offer help.
Date Created
2020-05
Agent

No evidence of an effect of resource necessity and unpredictability on cognitive mechanisms for detecting greediness and stinginess

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Description
Resource transfers can confer many adaptive benefits such as specialization, helping genetically related individuals, future compensation, and risk-pooling. Need-based transfers are a risk-pooling mechanism in which partners mitigate unpredictable losses by transferring resources based on need. Need-based transfers are likely…

Resource transfers can confer many adaptive benefits such as specialization, helping genetically related individuals, future compensation, and risk-pooling. Need-based transfers are a risk-pooling mechanism in which partners mitigate unpredictable losses by transferring resources based on need. Need-based transfers are likely to be most useful for resources that are necessary and unpredictable because being unable to reliably obtain essential resources would be devastating. However, need-based transfers make people vulnerable to two types of exploitation: a person can be greedy by asking when not in need and a person with a surplus of resources can be stingy by not giving to someone in need. Previous research suggests that people might have cognitive mechanisms for detecting greediness and stinginess, which would serve to protect against exploitation by cheaters. This study investigated whether resources that are necessary and unpredictable are most likely to trigger greediness and stinginess detection mechanisms. Participants saw four types of rules. One rule could be violated through greedy behavior, another through stingy behavior, another by not paying a debt, and another was a descriptive rule that could be violated by not finding one type of resource near another type of resource. Then, participants saw information about events relating to one of the rules and indicated whether the rule in question could have been violated. Consistent with past research, participants were better at detecting greediness, stinginess, and debts not paid than at detecting violations of a descriptive rule. However, contrary to my predictions, the necessity and unpredictability of resources did not impact people’s ability to detect greediness and stinginess. The lack of support for my hypothesis might be because the benefits of detecting greediness and stinginess might outweigh the costs even for situations in which need-based transfer rules are unlikely to apply, because people might be able to consciously activate their greediness and stinginess mechanisms even for resources that would not naturally trigger them, or because of methodological limitations.
Date Created
2019
Agent
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