Evolution Commons^™

Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi

Graduate Theses and Dissertations

Schizothorax (Snowtrout) is a genus of medium-sized minnows (Cypriniformes) inhabiting glacier-fed streams, rivers, and lakes in the Himalayas. There are more than 30 species of Schizothorax across the region. The speciation and diversity of the Snowtrout in the vast hinterlands of the Himalayan Region has not been fully explored. Three species in Lake Rara, Western Nepal are considered a species flock, comprising endemic ecotypes that are morphologically differentiated and reproductively isolated.

My dissertation research examined the diversity of Schizothorax in the Central Himalayan region and evolutionary relationships among species distributed in the Tibet, Central and Southeast Asia. Chapter I describes …

Phylogeny Of The Australian Solanum Dioicum Group Using Seven Nuclear Genes: Testing Symon’S Fruit And Seed Dispersal Hypotheses., Christopher T. Martine, Ingrid E. Jordon-Thaden, Angela J. Mcdonnell, Jason T. Cantley, Daniel S. Hayes, Morgan D. Roche, Emma S. Frawley, Ian S. Gilman, David C. Tank

Faculty Journal Articles

The dioecious and andromonoecious Solanum taxa (the “S. dioicum group”) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed dispersal. We combine field/greenhouse observations and specimen-based study with phylogenetic analysis of seven nuclear regions obtained via a microfluidic PCR-based enrichment strategy and high-throughput sequencing, and present the first species-tree hypothesis for the S. dioicum group. Our results suggest that epizoochorous trample burr seed …

Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars …

Changes In North American Mammal Niche Preferences From The Late Pleistocene To The Present, Silvia Pineda-Munoz, Anikó Tóth, S. Kathleen Lyons, Yue Wang, Jenny Mcguire

School of Biological Sciences: Presentations

Human population has exponentially grown since the last glaciation, especially across temperate areas with easy access to water sources, excluding mammal species from their former habitats. Thus, we anticipate a change in environmental niche preferences for temperature and precipitation as increased human population forces mammal species into more extreme climates within their environmental tolerances. For our study, we collected species occurrences from 20,000 ybp to the present for 59 North American mammal species. We inferred temperature and precipitation for each location using paleoclimate simulations (CCSM3). Overall, we found that mammals now live in areas that are warmer and dryer on …

Multiple Connections Between Amazonia And Atlantic Forest Shaped The T Phylogenetic And Morphological Diversity Of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae), Rafael O. De Sá, João Filipe Riva Tonini, Hannah Van Huss, Alex Long, Travis Cuddy, Mauricio C. Forlani, Pedro L.V. Peloso, Hussam Zaher, Célio F.B. Haddad

Biology Faculty Publications

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times …

Life History Of The Coastal Tailed Frog (Ascaphus Truei) Across An Elevational Gradient, Adrian Daniel Macedo

Cal Poly Humboldt theses and projects

The life history of a species is described in terms of its growth, longevity, and reproduction. Unsurprisingly, life history traits are known to vary in many taxa across environmental gradients. In the case of amphibians, species at high elevations and latitudes tend to have shorter breeding seasons, shorter activity periods, longer larval periods, reach sexual maturity at older ages, and produce fewer and larger clutches per year.

The Coastal Tailed Frog (Ascaphus truei) is an ideal species for the study of geographic variation in life history because it ranges across most of the Pacific Northwest from northern California …

Intelligence, Complexity, And Individuality In Sheep, Lori Marino, Debra Merskin

Animal Sentience

Domestic sheep (Ovis aries) are among the earliest animals domesticated for human use. They are consumed worldwide as mutton, hogget, and lamb, kept as wool and milk producers, and used extensively in scientific research. The popular stereotype is that sheep are docile, passive, unintelligent, and timid, but a review of the research on their behavior, affect, cognition, and personality reveals that they are complex, individualistic, and social.

Sacrificial Lambs, Clive Phillips

Animal Sentience

Sheep evolved from the mouflon as mountain animals, able to escape predation by leaping between rock ledges. Their defense was their agility. Humans brought them to the plains, where the agility was less useful, but their lack of aggression, speed or weaponry against predators made them a prime target to become one of man’s meat providers. A perfect animal in many ways, with extraordinary perceptive powers and some remarkable cognitive skills, they are often treated with complete disregard for their welfare. Yet sheep themselves won’t tell us this, for a sheep that alerted others to its weakness really would be …

Pulling The Wool From Our Eyes, Jennifer Vonk

Animal Sentience

Marino & Merskin review evidence of the complexity of sheep cognition, concluding that researchers ought to feel sheepish about misrepresenting ovine cognitive capacities. However, the failure to situate the data in critical context risks pulling the wool over readers’ eyes.

Is Knowing Enough To Change Human Attitudes And Actions?, Liv Baker

Animal Sentience

Marino & Merskin present evidence on key aspects of cognition, such as theory of mind, learning, emotional valence, and sociality, to make a convincing argument that sheep are due consideration as individual sentient beings. With this information, what will it take to produce a real, meaningful shift in our attitudes and actions towards other animals, including a species as disadvantaged as sheep? What else do we need to know?

Reflections On Sheep Rearing, Joyce D'Silva

Animal Sentience

Sheep rearing has an incredibly long history. Sometimes this alone can give credibility and status to a human practice. In the twenty-first century, it may be time to reassess our treatment of sheep and their place in nature. “Just because we’ve always done it” no longer has validity by itself. There are many other human practices which used to be accepted widely in certain societies and which we now may find abhorrent. With sheep intelligence now rightly regarded as an acceptable area of research within the academic community, it is a good time to reflect on our treatment of these …

Casting A Sheep’S Eye On Science, David M. Peña-Guzmán

Animal Sentience

Marino & Merskin review evidence that sheep are not just passive and reactive creatures. They have personalities that vary from individual to individual and endure over time. It follows that we must rethink what it means to study them scientifically.

Far More To Sheep Than Meets The Casual Eye, Bernard Rollin

Animal Sentience

Marino & Merskin’s survey of the cognitive and social capacities of sheep is an eye-opener about the individuality and emotionality of this most maligned of all farm animals. My own eyes had already been opened by an adopted orphaned lamb, so much more like a dog as a companion animal than the mindless robot I had been conditioned to expect. I am morally certain that Marino & Merskin’s survey will have a similar effect on readers open to changing their minds.

Sentient Animals Do Not Just Live In The Present, John Webster

Animal Sentience

Sheep are particularly well-equipped with the cognitive and emotional skills appropriate to their phenotype and natural environment. These include spatial memory, the benefits of safety in numbers, and the ability to recognise special individuals in large flocks by sight and by sound. Marino & Merskin’s target article reviews convincing evidence on whether sheep are more or less clever than other mammalian species. Sheep are very good at being sheep. But sentient animals do not just live in the present. Their emotional state is not simply dictated by events of the moment. If they learn, they can cope; if not, they …

Positive Sentience Is Underrated, Teya Brooks Pribac

Animal Sentience

My commentary focuses on two aspects of ovine (well-)being considered in the review: the developmental context and (un)fulfilled potentialities.

Sheep In Aesop’S And Phaedrus’S Fables, Matteo Colombo, Chiara Raucea

Animal Sentience

Sheep feature in various animal fables. Marino & Merskin suggest that “we” view sheep as “docile, passive, unintelligent, and timid,” but animal fables do not support this view. In Aesop’s and Phaedrus’s fables, sheep are a primary target of injustice; but they are not passive targets. Sheep endure injustice actively and honestly. They are intelligent, aware and outspoken about their own condition.

Using Sheep Psychology To Guide Sheep Policy, Ralph Adolphs

Animal Sentience

Marino & Merskin’s valuable review of the literature on sheep cognition shows how entrenched common views of these animals’ mental lives are disputed by the research literature. Yet the evidence they muster faces three challenges that their target article does not discuss: (1) the behavioral tasks are strongly anthropocentric; (2) neuroscientific data are absent; and (3) applications are not discussed. I touch on all three of these here.

Why Are Sheep Sheepish? How Perception Affects Animal Stereotyping, Robert G. Franklin Jr.

Animal Sentience

Marino & Merskin present compelling evidence that many stereotypes of sheep are incorrect. One factor that may play an important role in animal stereotyping is the physical appearance of animals, which can directly lead to stereotyping through automatic mental processes. Sheep have a round and babyish appearance that directly evokes judgments of warmth and docility. Depictions of sheep in art, and especially cartoons, reinforce this stereotype.

Debunking Human Prejudice And Blindness, Peter J. Li

Animal Sentience

Human prejudice and blindness to animal suffering are shocking. Despite their differences in culture, politics, and religious beliefs, humans have one thing in common. They see nonhuman animals as inferior and have since time immemorial assumed a dominant position in an asymmetrical human-animal relationship. When it comes to human-animal relations, there is no “clash of civilizations.” Human prejudice and blindness are predicated on “common sense assumptions” about the natural world and nonhuman animals in particular. Marino & Merskin’s review is part of the growing effort to debunk the assumptions that have shaped human actions so as to end the injustice …

Sheep Complexity Outside The Laboratory, Cheryl Abbate

Animal Sentience

Marino & Merskin’s review shows that sheep are intelligent and highly social but their methodology has some shortcomings. I describe five problems with reviewing only the academic and scientific literature and suggest how one might provide an even more compelling case for the complexity of sheep minds.

Cognition, Emotion, Personality And The Conservation And Management Of Wild Ungulates, Rob Found

Animal Sentience

Increasing public understanding of the complexity of wild ungulates can improve animal welfare and advance global conservation efforts of these keystone species. Unfortunately, shaping public opinion on wild species is challenging because personal experience with wildlife is declining, popular education is still biased towards the predator instead of the prey, and scientific research is more difficult to conduct on wild ungulates compared to those on farms, in zoos, or otherwise in captivity. Nevertheless, studies of cognition, individuality, and intelligence of wild ungulates are increasing. I briefly highlight some major results from my own work on complexity in wild elk, illustrating …

What Every Shepherd Knows, Marthe Kiley-Worthington

Animal Sentience

The findings of the research reviewed by Marino & Merskin have been common knowledge to shepherds for millennia. Many of them are also evolutionary necessities for all mammals, especially social ones.

The Intelligence Of Sheep, David Gamez

Animal Sentience

This commentary suggests how recent theories about the predictive brain could help us understand the evidence put forward by Marino & Merskin for intelligence in sheep. I contrast predictive intelligence in sheep with automatic behaviors that do not require intelligence, and I consider the flexibility of sheep intelligence.

Time To Vary The Formula, Jon Mallatt

Animal Sentience

In the past few years, Marino and her colleagues have written a series of comprehensive and helpful review articles on the cognitive, emotional, and social complexity of pigs, chickens, cows, and most recently, sheep. These articles are similarly structured, even formulaic, which has benefits but also limitations. Here, I point out the limitations in order to suggest new directions and contributions for the authors in the future.

The Importance Of Research Applicability, Krista Mclennan

Animal Sentience

Marino & Merskin’s (2019) review contains key information about the complexity of sheep and their intelligence level, but lacks practical application. The key to making any long-term changes to sheep welfare at an industry level is by generating research that is practically relevant to the sector. The practical application of research should be considered at the design stage and in consultation with producers. Additionally, thought needs to be given to how the practical application of the research will be transferred to those people directly involved in animal care (e.g., producers, stockpersons, etc.). Focusing on the practical relevance and application of …

Adding Sheep To The Spectrum Of Comparative Psychology, James King

Animal Sentience

Marino & Merskin’s comprehensive review of cognitive complexity in sheep is a laudable and important contribution to comparative psychology. It is also valuable because it shows promising directions for future research on this neglected species. The relatively small number of neurons in the bovid cerebral cortex indicates that sheep cognitive performance on traditional measures of complex learning is limited. Nevertheless, the social and emotional complexity of sheep underscores the importance of further research into domains including personality and psychological well-being.

Can A Mirror Capture The Self?, Cynthia Willett

Animal Sentience

Is the mirror a reliable indicator of self-awareness for any species, whether sheep or human? Taking a cue from feminist, phenomenological, and cross-cultural philosophy, a relational self rather than a reflective one might better capture what is at stake for the lives of social animals and for science.

A Behaviorist Approach To Sheep Cognition, Intelligence, And Welfare, Lindsay R. Mehrkam

Animal Sentience

Marino & Merskin’s review sheds light on the complexity of the mind, learning, and cognition of sheep. Readily observable behavior has value in its own right for promoting the well-being of animals. A behavior-analytic approach can add substantially to the understanding of sheep as individuals as well as their learning capacities. The findings can also be applied to arranging their environments to promote their well-being as well as behavioral change in those responsible for their care and management.

Complexity Of Wild Ruminants, Ozy Brennan

Animal Sentience

Marino & Merskin discuss ways that popular culture winds up depicting sheep as meek and unintelligent rather than as the complex, social species they are. I extend their analysis to apply to wild ruminants, particularly deer.

Cognitive Dissonance About Sheep Cognition And Consumption, Catia Correia Caeiro

Animal Sentience

Sheep are perceived as mere resources under the massive demand of the food and wool industry. Evidence that sheep cognition is comparable to that of other species may inspire reflection on sheep consumption. Dogs may be a promising comparison species.