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Animal Suicide: An Account Worth Giving?, Irina Mikhalevich 2018 Rochester Institute of Technology

Animal Suicide: An Account Worth Giving?, Irina Mikhalevich

Animal Sentience

Peña-Guzmán (2017) argues that empirical evidence and evolutionary theory compel us to treat the phenomenon of suicide as continuous in the animal kingdom. He defends a “continuist” account in which suicide is a multiply-realizable phenomenon characterized by self-injurious and self-annihilative behaviors. This view is problematic for several reasons. First, it appears to mischaracterize the Darwinian view that mind is continuous in nature. Second, by focusing only on surface-level features of behavior, it groups causally and etiologically disparate phenomena under a single conceptual umbrella, thereby reducing the account’s explanatory power. Third, it obscures existing analyses of suicide in biomedical ethics and …


Can Nondolphins Commit Suicide?, David M. Peña-Guzmán 2018 San Francisco State University

Can Nondolphins Commit Suicide?, David M. Peña-Guzmán

Animal Sentience

This Response addresses the scientific and philosophical criticisms of my 2017 target article “Can nonhuman animals commit suicide?” It defends my key claims and explores topics (such as animal judgment, animal theory of mind, and the evolution of suicide) that did not appear in the original article. It also points out areas in which further research is needed and concludes that we should be wary of accusations of “anthropomorphism” in debates about animal suicide.


Animal Suicide: Evolutionary Continuity Or Anthropomorphism?, Antonio Preti 2018 Centro Medico Genneruxi

Animal Suicide: Evolutionary Continuity Or Anthropomorphism?, Antonio Preti

Animal Sentience

Evolutionary processes are characterized by both continuity and discontinuity. Evidence on suicide in nonhuman animals is faint and often rests on the metaphorical or anthropomorphic use of the term. Suicidal behavior might be an evolutionary jump relatively recent in our species: a byproduct of living in groups of people who are not as closely related genetically as in social groups of nonhuman mammals.


Roots Of Self-Preservation Failure In Animal Behavior, Denys deCatanzaro 2018 McMaster University

Roots Of Self-Preservation Failure In Animal Behavior, Denys Decatanzaro

Animal Sentience

Affective variation from euphoria to dysphoria, best understood in humans, is also found in the behavior and neurochemistry of many other mammals. Suicide in humans typically occurs in highly dysphoric and despondent individuals. Self-injurious behavior has been observed in dysphoric and despondent nonhuman primates. In humans, suicide is facilitated by a highly-evolved neocortex giving rise to behavioral flexibility and culture. As Peña-Guzmán indicates, some other mammals also have elaborate neocortices and the capacity for cognitive insight, particularly apes, delphinids, and whales. Suicide is most likely to occur in species where individuals live in stable groups of highly interdependent kin.


Animal Suicide And "Anthropodenial", Ryan Hediger 2018 Kent State University - Tuscarawas Campus

Animal Suicide And "Anthropodenial", Ryan Hediger

Animal Sentience

Increasing understanding of the impressive cognitive and social capacities of nonhuman animals suggests the possibility that they may sometimes commit suicide. Such notions tend to be dismissed as “anthropomorphism.” That interpretive hazard, I argue, must be weighed against the opposite hazard of “anthropodenial” — “the a priori rejection of shared characteristics between humans and animals” (de Waal 2006). If animals do commit suicide, how often is it motivated precisely by the impact of humans on animal life?


Continuum And Temporality, Gerard Kuperus 2018 University of San Francisco

Continuum And Temporality, Gerard Kuperus

Animal Sentience

I fully support the continuum proposed in the target article and argue along the same lines that we should be suspicious of drawing any strict borders between human and non-human animals. Since we can say very little with absolute certainty about human intentions regarding suicide, we have no certainty about the intentions of non-human animals. Although I am very sympathetic to Peña-Guzmán’s overall argument, I suggest that time could be taken into consideration as well.


Thinking About Thinking Chickens, Lori Marino 2018 Animal Studies Repository

Thinking About Thinking Chickens, Lori Marino

Animal Sentience

This response focuses on three major conceptual threads that run through the peer commentary on my target article: (1) how the use of chickens influences our views of them, (2) whether education is effective, and (3) what components of chicken psychology are most relevant to understanding who chickens are.



The Life History Of Faxonius Rusticus (Girard, 1852) In Sunfish Creek, Monroe County, Ohio, Kyle McGill 2018 Marshall University

The Life History Of Faxonius Rusticus (Girard, 1852) In Sunfish Creek, Monroe County, Ohio, Kyle Mcgill

Theses, Dissertations and Capstones

Crayfish are among the most imperiled faunal groups globally. The continued spread of invasive species is a major impact to crayfish. Invasive species, much like the native species, are often understudied. As declines continue, invasive species spread, and new species are discovered; additional life history studies are as important as ever for crayfish conservation. Life history data was collected for rusty crayfish (Faxonius rusticus) from October 2017 to September 2018 in Sunfish Creek, Monroe County, Ohio. Faxonius rusticus are native to the Ohio River drainage around Cincinnati, Ohio but have extensively expanded their range over the past 30 years. Sunfish …


Multiple Signaling Functions Of Song In A Polymorphic Species With Alternative Reproductive Strategies, M. L. Grunst, A. S. Grunst, Vincent A. Formica, R. A. Gonser, E. M. Tuttle 2018 Swarthmore College

Multiple Signaling Functions Of Song In A Polymorphic Species With Alternative Reproductive Strategies, M. L. Grunst, A. S. Grunst, Vincent A. Formica, R. A. Gonser, E. M. Tuttle

Biology Faculty Works

Vocal traits can be sexually selected to reflect male quality, but may also evolve to serve additional signaling functions. We used a long-term dataset to examine the signaling potential of song in dimorphic white-throated sparrows (Zonotrichia albicollis). We investigated whether song conveys multifaceted information about the vocalizing individual, including fitness, species identity, individual identity, and morph. We also evaluated whether song traits correlate differently with fitness in the two morphs, as the more promiscuous strategy of white, relative to tan, morph males might impose stronger sexual selection. Males with high song rates achieved higher lifetime reproductive success, and this pattern …


Social Contact Patterns Can Buffer Costs Of Forgetting In The Evolution Of Cooperation, Jeffrey R. Stevens, Jan K. Woike, Lael J. Schooler, Stefan Lindner, Thorsten Pachur 2018 University of Nebraska-Lincoln

Social Contact Patterns Can Buffer Costs Of Forgetting In The Evolution Of Cooperation, Jeffrey R. Stevens, Jan K. Woike, Lael J. Schooler, Stefan Lindner, Thorsten Pachur

Jeffrey Stevens Publications

Analyses of the evolution of cooperation often rely on two simplifying assumptions: (i) individuals interact equally frequently with all social network members and (ii) they accurately remember each partner's past cooperation or defection. Here, we examine how more realistic, skewed patterns of contact—in which individuals interact primarily with only a subset of their network's members—influence cooperation. In addition, we test whether skewed contact patterns can counteract the decrease in cooperation caused by memory errors (i.e. forgetting). Finally, we compare two types of memory error that vary in whether forgotten interactions are replaced with random actions or with actions from previous …


Mesotocin Influences Pinyon Jay Prosociality, Juan Duque, Whitney Leichner, Holly Ahmann, Jeffrey R. Stevens 2018 University of Nebraska - Lincoln

Mesotocin Influences Pinyon Jay Prosociality, Juan Duque, Whitney Leichner, Holly Ahmann, Jeffrey R. Stevens

Jeffrey Stevens Publications

Many species exhibit prosocial behavior, in which one individual’s actions benefit another individual, often without an immediate benefit to itself. The neuropeptide oxytocin is an important hormonal mechanism influencing prosociality in mammals, but it is unclear whether the avian homologue mesotocin plays a similar functional role in birds. Here, we experimentally tested prosociality in pinyon jays (Gymnorhinus cyanocephalus), a highly social corvid species that spontaneously shares food with others. First, we measured prosocial preferences in a prosocial choice task with two different payoff distributions: Prosocial trials delivered food to both the subject and either an empty cage or a partner …


If Nonhuman Animals Can Suicide, Why Don’T They?, C. A. Soper, Todd K. Shackelford 2018 University of Gloucestershire, England

If Nonhuman Animals Can Suicide, Why Don’T They?, C. A. Soper, Todd K. Shackelford

Animal Sentience

An evolutionary analysis suggests that selection is unlikely to have tolerated the capacity for intentional self-killing in nonhuman animals. The potential to escape pain by suicide would have presented a recurrent and severe adaptive problem for an animal with a reproductive future to protect. If the potential for suicide arose in the evolutionary past, anti-suicide mechanisms may have co-evolved, as we believe they have in adult humans. Peña-Guzmán’s (2017) argument that some nonhuman animals can suicide is incomplete without an account of the defences that result in the vast majority opting not to.


Chicken Minds And Moral Standing, Kristin Andrews 2018 York University

Chicken Minds And Moral Standing, Kristin Andrews

Animal Sentience

Some of the cognitive traits that Marino reviews are not in themselves relevant to ethics, either for chickens or human infants, but affective traits are, among them desires.


Convergent Body Size Evolution Of Crocodyliformes Upon Entering The Aquatic Realm, William Gearty, Jonathan Payne 2018 University of Nebraska - Lincoln

Convergent Body Size Evolution Of Crocodyliformes Upon Entering The Aquatic Realm, William Gearty, Jonathan Payne

School of Biological Sciences: Presentations

Twenty-four species of crocodile populate the globe today, but this richness represents a minute fraction of the diversity and disparity of Crocodyliformes since their origin early in the Triassic. Across this clade, three major diversification events into the aquatic realm have occurred. Aquatic and terrestrial habitats impose differing selective pressures on body size. However, previous research on this topic in Crocodyliformes remains qualitative in nature. In this study, our goal was to quantify the influence of habitat (terrestrial versus aquatic) on the evolution of body size in Crocodyliformes. We find a history of repeated body size increase and convergence following …


Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori 2018 Virginia Commonwealth University

Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori

Theses and Dissertations

Specialization on insect and animal pollinators is thought to be the driving force for the evolution of floral traits. Specifically in the New World (NW), the oil-bee pollination syndrome has led to the convergence of floral characters in two distantly related families of core eudicots, Malpighiaceae and Krameriaceae. Both families display a flag-like structure that establishes a zygomorphic flower and floral oil rewards in epithelial elaiophores. These traits work concomitantly to attract and reward female oil-bees that help fertilize these flowers and in return receive oils. The underlying genetics of floral zygomorphy were studied in several clades of core eudicots, …


Comparative Phylogeography, Taxonomy, And Neuroanatomy Of Montane Chameleons In The Albertine Rift, Central Africa, Daniel Hughes 2018 University of Texas at El Paso

Comparative Phylogeography, Taxonomy, And Neuroanatomy Of Montane Chameleons In The Albertine Rift, Central Africa, Daniel Hughes

Open Access Theses & Dissertations

How do traits vary across the tree of life? Our ability to address this question is diminished if: A taxonomic group has a poorly sampled phylogeny, a species goes extinct before their systematic position is resolved, or a trait is inadequately characterized for detailed studies. In the current era of mass extinction, it is imperative to not only accelerate species discovery through traditional studies in taxonomy and expeditionary research, but also to increase rescue efforts for all types of data before poorly understood species and potentially undescribed traits are lost. Here, an integrative taxonomic approach was used and novel methods …


An Investigation Of Implicit And Explicit Memory In The Survival Memory Paradigm, Allison M. Wilck 2018 University at Albany, State University of New York

An Investigation Of Implicit And Explicit Memory In The Survival Memory Paradigm, Allison M. Wilck

Legacy Theses & Dissertations (2009 - 2024)

Robust support has been found for a survival processing effect on memory when information is encoded for its fitness-relevance (Nairne, Thompson, & Pandeirada, 2007). However, support for this effect has been limited to forms of memory that require intentional, explicit retrieval processes. Thus far, the literature has failed to identify the effect in implicit, automatic memory using conceptual and perceptual production tasks (McBride, Thomas, & Zimmerman, 2013; Tse & Altarriba, 2010). In the current study, an alternative implicit memory test that employs different memory processes was employed in a further attempt to examine the survival processing effect in implicit memory. …


Literature Review: Analyzing The Reasons Behind The Long-Standing Debate Of Evolution And Religion In America, Michelle Kathryn Matchell 2018 University of Northern Iowa

Literature Review: Analyzing The Reasons Behind The Long-Standing Debate Of Evolution And Religion In America, Michelle Kathryn Matchell

Honors Program Theses

Evolution has been a widely studied and debated topic for centuries. Since the days of Greek philosophy, humans have been curious about the diversity of life and how it arose to what we see today. Interest in evolution flourished during the days of Charles Darwin when he and Alfred Russel Wallace developed the concept of natural selection. Now, evolution is an integral part of many scientific studies, especially genetics, developmental biology, geology, behavior studies and social sciences. According to Muhammad Ashraf, evolution can be considered ‘the cornerstone of modern science’ (Ashraf, 2016). On what would have been Darwin’s 201st birthday, …


Dna Extraction And Microsatellite Amplification Of Daphnia Pulicaria Resting Eggs: Analysis Of Allele Frequencies Through Time, Anna Ries 2018 Hamline University

Dna Extraction And Microsatellite Amplification Of Daphnia Pulicaria Resting Eggs: Analysis Of Allele Frequencies Through Time, Anna Ries

Departmental Honors Projects

A paleoecological approach allows for the study of genetic change in populations over longer periods of time than would be possible if one were sampling populations from year to year. Daphnia and other cladoceran zooplankton are amenable to this type of study because they produce diapausing embryos (ephippial eggs) when they sexually reproduce, and these resting eggs can remain viable for decades to centuries in lake sediments. This study uses paleoecological methods as well as a new methodology for ephippial DNA extraction and amplification to assay for genetic variation in ephippial eggs obtained from sediments of varying ages from Square …


The Many Faces Of Fear And Vigilance, Guy Beauchamp 2018 Independent Researcher, Canada

The Many Faces Of Fear And Vigilance, Guy Beauchamp

Animal Sentience

In the target article, I examined the relationship between vigilance and fear in prey animals. The joint occurrence of vigilance and other physiological responses to fear, such as increased heart rate and stress hormone release, would bolster the idea that vigilance can be a useful marker of fear. Nevertheless, a common theme in much of the empirical research is an uncoupling of vigilance and physiological correlates of fear. The commentators suggest several ways to refine the concepts of vigilance, fear, and risk. I discuss these refinements, which in the end will prove useful to assess further the relationship between vigilance …


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